# Winter cod liver oil · Original null result for reduced serious COVID-19

Verdict 2972 · Evidence Check

Stored-material review date: Not recorded  
Original evidence cut-off: 2026-08-26  
Review-criteria version: 1.0  
Public page/material preparation date: 2026-10-14

Clinical papers were not read directly; existing review summaries were checked. No new clinical-literature search was performed. Unverified does not mean that research is absent or that there is no effect.

## Assessment scope

- Population: Norwegian adults not taking vitamin D supplements daily; original 34,601 randomized; direct serious-outcome risk/infected-population denominators unverified
- Ingredient, formulation and route: Winter cod liver oil 5 mL/day in adults not taking vitamin D supplements daily
- Dose: Original combination-study exposure preserved: cod liver oil 5 mL/day, vitamin D 10 µg/about 1 g n-3; no intake/conversion/management guidance
- Comparator: Flavour-matched corn-oil placebo; original randomized arm sizes 17,278/17,323
- Measured outcome: Selected serious COVID-19: original 121/101, RR 1.20/interval 0.87–1.65; exact composite/components/confirmation/denominator unverified
- Duration: Original about six winter months, median 164 days of use; distinguished from individual/event/risk periods, long-term follow-up and treatment scope
- Questions outside this scope: Repurposing serious events 121/101/RR as individual hospitalization/death components or treatment after infection; Adding PCR/negative tests/ARI or related claims as serious outcomes or independent trials; Copying full arm sizes/infection events as every risk-population/component denominator; Extending a null combination product to deficiency/high-dose/single ingredients, all current periods or treatment; Cod-liver-oil/vitamin/product-use, infection-prevention/COVID-19 management/serious-disease treatment or treatment-replacement instructions

## Checklist items

### N01 · How is the selected serious-COVID-19 claim distinguished from infection/respiratory claims?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The selected existing question is reduced serious COVID-19. Its subclaim record is linked; PCR infection and other acute respiratory infection remain original context. No new question, split or trial is created.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. No new certification of clinical independence was made.
- Reason for missing information: No new certification of clinical independence was made.
- Required materials and conditions: Selected serious-outcome question/record and parent/infection/other respiratory endpoints
- Materials to obtain first: Original question/event definitions, population/comparator and scope-change records
- Further research: A plan distinguishing infection, serious outcomes and other respiratory results
- Conditions for verification: For Selected serious-outcome question/record and parent/infection/other respiratory endpoints, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How is the selected serious-COVID-19 claim distinguished from infection/respiratory claims?
- Application exceptions: Do not repurpose PCR/symptom results as direct effects on the selected serious outcome or add new related units.
- Remaining uncertainty: No new certification of clinical independence was made.
- Referenced methods: M03 §3.1, §3.2.1–3.2.4 principles for clarifying questions; Detailed separation rules are a custom design; M04 §4.6.1–4.6.2 distinction between studies and reports; Cohort/outcome linkage is a custom application; M03 §3.2.4; Custom extension boundary
- Related sources: R01

### N02 · What are the selected D/note and absent score/status/axes?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Selected D and the note “Null, RR 1.20 (0.87–1.65)” are preserved. Subclaim score/status/axes are absent; parent D with 34 points and its axes remain separate historical context.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Subclaim score/status/axes are absent from the original.
- Reason for missing information: Subclaim score/status/axes are absent from the original.
- Required materials and conditions: Subclaim D, RR 1.20 (0.87–1.65) and parent history
- Materials to obtain first: Original subclaim and explicit change events
- Further research: Separate original grades from new evidence/changes
- Conditions for verification: For Subclaim D, RR 1.20 (0.87–1.65) and parent history, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the selected D/note and absent score/status/axes?
- Application exceptions: Do not repurpose parent 34 points or H/E0/C0/B0 axes as subclaim values or current clinical review/efficacy certification.
- Remaining uncertainty: Subclaim score/status/axes are absent from the original.
- Referenced methods: M03 §3.1, §3.2.1–3.2.4 question-clarification principles; detailed separation rules are internally designed; M04 §4.5, §4.6.3; limits of this material conversion follow the review scope and internal design
- Related sources: R01

### N03 · What are the population and routine vitamin-D supplementation boundaries?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original concerns winter cod liver oil in adults not taking vitamin D supplements daily and records 34,601 Norwegian adults. It does not directly establish results for deficiency treatment or every adult.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Age/sex, selection/exclusions, baseline conditions/vitamin status and infection risk remain unverified.
- Reason for missing information: Age/sex, selection/exclusions, baseline conditions/vitamin status and infection risk remain unverified.
- Required materials and conditions: Norwegian adults, no routine daily supplements, selection/baseline
- Materials to obtain first: Selection criteria and baseline/vitamin-status tables
- Further research: Research specifying the population and routine-supplement scope
- Conditions for verification: For Norwegian adults, no routine daily supplements, selection/baseline, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the population and routine vitamin-D supplementation boundaries?
- Application exceptions: Do not extend to deficiency treatment, specific risk groups/every adult or intake guidance.
- Remaining uncertainty: Age/sex, selection/exclusions, baseline conditions/vitamin status and infection risk remain unverified.
- Referenced methods: M03 §3.2.1; detailed population conditions are internally designed; M04 §4.6.1–4.6.2, M15 §15.3.1; internal application
- Related sources: R01

### N04 · What separates winter/the trial period from current variants, vaccination and treatment?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original describes about six winter months, registration posted 2020-10-30 and start 2020-11-10. Details of variants, vaccination/previous infection and concurrent treatment are absent from the summary.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Period-specific pathogens/vaccination, previous infection, exposure/treatment and subgroups remain unverified.
- Reason for missing information: Period-specific pathogens/vaccination, previous infection, exposure/treatment and subgroups remain unverified.
- Required materials and conditions: Original winter period, stated 2020 start and baseline/period exposures
- Materials to obtain first: Actual period/baseline exposures and pathogen/treatment data
- Further research: Research distinguishing period/population boundaries
- Conditions for verification: For Original winter period, stated 2020 start and baseline/period exposures, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What separates winter/the trial period from current variants, vaccination and treatment?
- Application exceptions: Do not newly establish the winter result for all current variants/vaccination states or serious-COVID-19 treatment efficacy.
- Remaining uncertainty: Period-specific pathogens/vaccination, previous infection, exposure/treatment and subgroups remain unverified.
- Referenced methods: M03 §3.2.1; detailed population conditions are internally designed; M04 §4.6.1–4.6.2, M15 §15.3.1; internal application; M03 §3.2.3, M08 §8.2.2–8.2.3; internal application
- Related sources: R01

### N05 · What was the original combination-product exposure at 5 mL/day?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original cod liver oil 5 mL/day contained vitamin D 10 µg and about 1 g of n-3 fatty acids. The original Möller’s Tran manufacturer-product description is preserved; the combination is not split into single-ingredient effects.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Composition/manufacture/quality, other ingredients and actual adherence/exposure specifications remain unverified.
- Reason for missing information: Composition/manufacture/quality, other ingredients and actual adherence/exposure specifications remain unverified.
- Required materials and conditions: Cod liver oil, vitamin D 10 µg/about 1 g n-3 and original product identity
- Materials to obtain first: Study-product specifications and actual exposure/adherence records
- Further research: Research specifying combination product/population exposure
- Conditions for verification: For Cod liver oil, vitamin D 10 µg/about 1 g n-3 and original product identity, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What was the original combination-product exposure at 5 mL/day?
- Application exceptions: No new dose conversion, cod-liver-oil/vitamin/product-use instructions, ingredient recommendations or treatment methods.
- Remaining uncertainty: Composition/manufacture/quality, other ingredients and actual adherence/exposure specifications remain unverified.
- Referenced methods: M03 §§3.2.2–3.2.3; reverse-direction labels and assessment adaptation are Chamgap-designed; M03 §§3.2.1–3.2.4; dose, durability and effect-modification details are Chamgap-designed
- Related sources: R01

### N06 · What does the flavour-matched corn-oil comparator answer?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original compares flavour-matched corn-oil placebo, 17,323 adults, with cod liver oil, 17,278. This was not a comparison with no treatment, high-dose vitamins or omega-3 alone.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Comparator composition/exposure, condition recognition/actual adherence and shared procedures remain unverified.
- Reason for missing information: Comparator composition/exposure, condition recognition/actual adherence and shared procedures remain unverified.
- Required materials and conditions: Original corn-oil placebo, sensory features/composition/common conditions
- Materials to obtain first: Active/placebo specifications and masking/adherence data
- Further research: A plan specifying the exact comparator and estimand
- Conditions for verification: For Original corn-oil placebo, sensory features/composition/common conditions, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What does the flavour-matched corn-oil comparator answer?
- Application exceptions: Do not turn the combination-product comparison into new superiority claims for single ingredients, all products or other treatments.
- Remaining uncertainty: Comparator composition/exposure, condition recognition/actual adherence and shared procedures remain unverified.
- Referenced methods: M03 §3.2.2–3.2.3; reverse-direction labels and testing adaptations are internally designed; M03 §3.2.3, M08 §8.2.2–8.2.3; internal application; M08 §8.1–8.2.3; internal application
- Related sources: R01

### N07 · How are a median 164 days/about six months separated from actual exposure/follow-up?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original records a median 164 days of use and about six winter months. Individual exposure durations, adherence/discontinuation and infection/serious-outcome follow-up times are not detailed in the summary.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Individual/arm-specific exposure, adherence/discontinuation, time at risk and outcome observation remain unverified.
- Reason for missing information: Individual/arm-specific exposure, adherence/discontinuation, time at risk and outcome observation remain unverified.
- Required materials and conditions: Median 164 days of use, winter period, outcome observation/adherence
- Materials to obtain first: Exposure/outcome timing and adherence/follow-up records
- Further research: Research separating exposure from event-observation periods
- Conditions for verification: For Median 164 days of use, winter period, outcome observation/adherence, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How are a median 164 days/about six months separated from actual exposure/follow-up?
- Application exceptions: Do not calculate 164 days as a fixed duration for everyone, total product amounts or person-time, or provide an intake schedule.
- Remaining uncertainty: Individual/arm-specific exposure, adherence/discontinuation, time at risk and outcome observation remain unverified.
- Referenced methods: M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptations are internally designed; M03 §3.2.1–3.2.4; dose/duration/effect-modification details are internally designed; M08 §8.2.2, M15 §15.3.1; internal application
- Related sources: R01

### N08 · What is the exact serious-COVID-19 event/composite definition?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original records serious COVID-19 as one coprimary outcome. Exact severity criteria, composite components/adjudication and confirmation methods are not provided in the summary.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Composite definition/components, thresholds, testing/physician adjudication and confirmation timing remain unverified.
- Reason for missing information: Composite definition/components, thresholds, testing/physician adjudication and confirmation timing remain unverified.
- Required materials and conditions: Serious-outcome definition, confirmation, composite/components and thresholds
- Materials to obtain first: Serious-outcome definitions, adjudication/confirmation plans and original component tables
- Further research: Research specifying the serious composite and individual components
- Conditions for verification: For Serious-outcome definition, confirmation, composite/components and thresholds, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What is the exact serious-COVID-19 event/composite definition?
- Application exceptions: Do not newly define severity using hospitalization/death alone or add symptoms/components absent from the original.
- Remaining uncertainty: Composite definition/components, thresholds, testing/physician adjudication and confirmation timing remain unverified.
- Referenced methods: M03 §3.2.4 and M15 §15.3.1–15.3.3; Question-specific outcome adaptation is Chamgap design; M08 Table 8.2.a and M03 §3.2.4; Chamgap application; M03 §3.2.4; Chamgap interpretation boundary
- Related sources: R01

### N09 · What are the selected serious-outcome events, RR and adjusted interval?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Following the original endpoint order, serious outcomes were cod liver oil 121 versus placebo 101, RR 1.20 (0.87–1.65). Korean/English text describes adjusted 95% intervals and the original null result. No new RR/CI/P is calculated.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Whether events count people, first/repeated events or composite events, and the relevant denominator/model/adjustment method, remain unverified.
- Reason for missing information: Whether events count people, first/repeated events or composite events, and the relevant denominator/model/adjustment method, remain unverified.
- Required materials and conditions: Serious outcomes: 121 versus 101, RR 1.20 (0.87–1.65)
- Materials to obtain first: Serious-outcome events/denominators and RR/interval/analysis tables
- Further research: Research specifying estimand, events/denominators and adjustment
- Conditions for verification: For Serious outcomes: 121 versus 101, RR 1.20 (0.87–1.65), separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the selected serious-outcome events, RR and adjusted interval?
- Application exceptions: Do not turn RR>1 into confirmed harm/a significant increase or certify the original null result as exactly zero effect/equivalence.
- Remaining uncertainty: Whether events count people, first/repeated events or composite events, and the relevant denominator/model/adjustment method, remain unverified.
- Referenced methods: M08 Table 8.2.a, M15 §15.3 and M19 §19.1.2–19.2.4; Design-specific adaptation is Chamgap design; M08 §8.2.2 and M15 §15.3.1; Chamgap application; M15 §15.3.1–15.3.3; Chamgap application
- Related sources: R01

### N10 · Is hospitalization the same as the individual effect of the serious composite?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original serious-event totals 121/101 and RR exist, but hospitalization components/inclusion, original events/denominators and effect/CI are not separately available. The composite result is not copied as a hospitalization result.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Hospitalization components, definition/confirmation, events/denominators/time and effect intervals remain unverified.
- Reason for missing information: Hospitalization components, definition/confirmation, events/denominators/time and effect intervals remain unverified.
- Required materials and conditions: Hospitalization definition/confirmation, events/denominator and composite relationship
- Materials to obtain first: Original hospitalization/serious-component tables and direct definitions
- Further research: A plan distinguishing the composite from individual hospitalization outcomes
- Conditions for verification: For Hospitalization definition/confirmation, events/denominator and composite relationship, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Is hospitalization the same as the individual effect of the serious composite?
- Application exceptions: Do not transfer 121/101 to hospitalization counts or create zero hospitalizations or reduction/increase effects.
- Remaining uncertainty: Hospitalization components, definition/confirmation, events/denominators/time and effect intervals remain unverified.
- Referenced methods: M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptations are internally designed; M08 Table 8.2.a, M15 §15.3, M19 §19.1.2–19.2.4; design-specific adaptations are internally designed; M03 §3.2.4; internal extension boundaries
- Related sources: R01

### N11 · Is death the same as the individual effect of the serious composite?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original summary lacks individual COVID-19/all-cause-death components, events/denominators and effect/CI. The serious-outcome RR is not transferred to a mortality RR.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Cause-specific/all-cause death, composite inclusion, events/denominators/time and estimates/CI remain unverified.
- Reason for missing information: Cause-specific/all-cause death, composite inclusion, events/denominators/time and estimates/CI remain unverified.
- Required materials and conditions: Death definition/period, components/individual events and denominator
- Materials to obtain first: Original mortality/serious-component tables and definitions/follow-up
- Further research: A plan separating serious composites from cause-specific/all-cause mortality
- Conditions for verification: For Death definition/period, components/individual events and denominator, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Is death the same as the individual effect of the serious composite?
- Application exceptions: Do not add zero deaths or sparse-event counts absent from the original, or judge null serious outcomes as mortality equivalence/no harm.
- Remaining uncertainty: Cause-specific/all-cause death, composite inclusion, events/denominators/time and estimates/CI remain unverified.
- Referenced methods: M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptations are internally designed; M08 Table 8.2.a, M15 §15.3, M19 §19.1.2–19.2.4; design-specific adaptations are internally designed; M03 §3.2.4; internal extension boundaries
- Related sources: R01

### N12 · Are randomized, infected and at-risk population denominators distinguished?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original randomization of 34,601 adults (17,278/17,323) is preserved. The exact serious-event risk denominator, conditional serious-outcome denominator among PCR-infected participants and risk subgroups are not separately available.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Outcome-specific effective denominators/infection conditions, time/subgroups and event aggregation remain unverified.
- Reason for missing information: Outcome-specific effective denominators/infection conditions, time/subgroups and event aggregation remain unverified.
- Required materials and conditions: 34,601/arm sizes versus serious-outcome/infected/event-risk denominators
- Materials to obtain first: Randomized/infected/at-risk population flow and outcome-specific denominators
- Further research: Research distinguishing populations, denominators and conditional estimands
- Conditions for verification: For 34,601/arm sizes versus serious-outcome/infected/event-risk denominators, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Are randomized, infected and at-risk population denominators distinguished?
- Application exceptions: Do not use PCR 227/228 as serious-outcome denominators or copy full arm sizes to every component/subgroup.
- Remaining uncertainty: Outcome-specific effective denominators/infection conditions, time/subgroups and event aggregation remain unverified.
- Referenced methods: M08 Table 8.2.a, M15 §15.3, M19 §19.1.2–19.2.4; design-specific adaptations are internally designed; M03 §3.2.1; detailed population conditions are internally designed; M08 §8.2.2, M15 §15.3.1; internal application
- Related sources: R01

### N13 · What is the uncertainty in serious/component events and intervals?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original serious events 121/101, RR 1.20, interval 0.87–1.65 and parent C0 are preserved. A large overall sample does not guarantee precision, exclusion of small differences or equivalence for each component.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Component events/denominators, estimates/CI, power/importance and sparse-event handling remain unverified.
- Reason for missing information: Component events/denominators, estimates/CI, power/importance and sparse-event handling remain unverified.
- Required materials and conditions: Original events/intervals, component sparsity/precision and importance
- Materials to obtain first: Component-specific events/estimates/intervals and SAP
- Further research: A plan distinguishing overall sample size from outcome-specific precision
- Conditions for verification: For Original events/intervals, component sparsity/precision and importance, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What is the uncertainty in serious/component events and intervals?
- Application exceptions: Do not calculate new P/CI where original intervals/P are absent or newly conclude that all important benefits/harms are excluded.
- Remaining uncertainty: Component events/denominators, estimates/CI, power/importance and sparse-event handling remain unverified.
- Referenced methods: M15 §15.3.1–15.3.3; Chamgap adaptation; M08 Table 8.2.a, M15 §15.3, M19 §19.1.2–19.2.4; design-specific adaptations are Chamgap design
- Related sources: R01

### N14 · How are PCR infection, negative tests and other ARI different endpoints?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original PCR 227/228, RR 1.00 (0.82–1.22); negative tests 8,546/8,565, RR 1.00 (0.97–1.04); and self-reported ARI 3,964/3,834, RR 1.04 (0.97–1.11), are preserved as other-endpoint context.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Event definitions/confirmation, people/tests/repetition and denominators/models for each endpoint remain unverified.
- Reason for missing information: Event definitions/confirmation, people/tests/repetition and denominators/models for each endpoint remain unverified.
- Required materials and conditions: Original order of four results, related outcomes, negative tests and questionnaire ARI
- Materials to obtain first: Each endpoint definition/denominator and original result tables
- Further research: A plan separating infection, tests, symptoms and serious outcomes
- Conditions for verification: For Original order of four results, related outcomes, negative tests and questionnaire ARI, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How are PCR infection, negative tests and other ARI different endpoints?
- Application exceptions: Do not turn negative tests into other confirmed infections or sum the four event counts/related claims into serious outcomes or independent trials.
- Remaining uncertainty: Event definitions/confirmation, people/tests/repetition and denominators/models for each endpoint remain unverified.
- Referenced methods: M03 §3.1, §3.2.1–3.2.4 question-clarification principles; detailed splitting rules are internally designed; M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptations are internally designed; M03 §3.2.4; internal extension boundaries
- Related sources: R01

### N15 · What was the original scope of four coprimary outcomes, fallback and adjusted intervals?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original describes all four coprimary outcomes as null and multiplicity control through prespecified fallback. Original adjusted 95% intervals are preserved; exact rules/adjustments/original plans remain externally unread.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Fallback allocation/success rules, interval/model adjustment and plan versions remain unverified.
- Reason for missing information: Fallback allocation/success rules, interval/model adjustment and plan versions remain unverified.
- Required materials and conditions: Coprimary hierarchy, multiplicity/fallback and interval adjustment
- Materials to obtain first: Registration/protocol/SAP and multiplicity/interval plans
- Further research: Research specifying coprimary outcomes, estimands and multiplicity
- Conditions for verification: For Coprimary hierarchy, multiplicity/fallback and interval adjustment, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What was the original scope of four coprimary outcomes, fallback and adjusted intervals?
- Application exceptions: Do not create current prospective-specification certification from four endpoint names/original B0 quotations or arbitrarily interpret interval adjustment as baseline-covariate adjustment.
- Remaining uncertainty: Fallback allocation/success rules, interval/model adjustment and plan versions remain unverified.
- Referenced methods: M08 Table 8.2.a, M04 §4.6.3; internal application; M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptations are internally designed; M15 §15.3.1–15.3.3; internal application
- Related sources: R01

### N16 · What is known from the registration ID/posting/start versus current plan reading?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original NCT04609423 and prospective registration posted 2020-10-30 before start 2020-11-10 are preserved. External registration, protocol and SAP were not queried/read this time.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Registration content/versions, prespecified outcomes/analyses and amendment/posting records remain unread.
- Reason for missing information: Registration content/versions, prespecified outcomes/analyses and amendment/posting records remain unread.
- Required materials and conditions: NCT04609423, original 2020-10-30/11-10 and prospective description
- Materials to obtain first: Registration versions/timing, protocol/SAP and result comparisons
- Further research: Records preserving prespecified plans and amendment events
- Conditions for verification: For NCT04609423, original 2020-10-30/11-10 and prospective description, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What is known from the registration ID/posting/start versus current plan reading?
- Application exceptions: Do not upgrade original prospective/matching quotations to current registration verification or completed plan review, or calculate date differences.
- Remaining uncertainty: Registration content/versions, prespecified outcomes/analyses and amendment/posting records remain unread.
- Referenced methods: M04 §4.5–4.6 material collection/selection principles; acquisition/reading separation and hyperlink specifications are internally designed; M04 §4.5, §4.6.3; limits of this material conversion follow the review scope and internal design; M08 Table 8.2.a, M04 §4.6.3; internal application
- Related sources: R01

### N17 · What do the original concealment/quadruple-masking quotations record?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original research explanation preserves quotations on hospital research-support allocation without investigator involvement and masking of participants, researchers, care, collection, assessment and analysis personnel. Actual procedures/condition recognition were not newly reviewed externally.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Allocation/concealment, maintained masking/condition comparability and baseline-balance details remain unread.
- Reason for missing information: Allocation/concealment, maintained masking/condition comparability and baseline-balance details remain unread.
- Required materials and conditions: Allocation without investigator involvement and masked participant/research/collection/assessment/analysis roles
- Materials to obtain first: Allocation/masking/condition-recognition and baseline/protocol data
- Further research: Research specifying exact allocation and masking roles
- Conditions for verification: For Allocation without investigator involvement and masked participant/research/collection/assessment/analysis roles, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What do the original concealment/quadruple-masking quotations record?
- Application exceptions: Do not inherit original B0/quadruple masking as current completed risk-of-bias/content review or independence certification.
- Remaining uncertainty: Allocation/concealment, maintained masking/condition comparability and baseline-balance details remain unread.
- Referenced methods: M08 §8.1–8.2.3; internal application; M08 Table 8.2.a, M03 §3.2.4; internal application
- Related sources: R01

### N18 · Is 0.05% key-variable missingness the same as missing events/components?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original 34,601/17,278/17,323 and 0.05% key-variable missingness are preserved. Endpoint/serious-component omissions, risk denominators and completed withdrawal/infection follow-up are not separately available.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Missingness by arm/endpoint/component, reasons for withdrawal/discontinuation and missing-data handling remain unverified.
- Reason for missing information: Missingness by arm/endpoint/component, reasons for withdrawal/discontinuation and missing-data handling remain unverified.
- Required materials and conditions: Randomized/arm sizes, 0.05% key variables and outcome-specific denominators/flow
- Materials to obtain first: Each flow/missingness table, SAP and collection materials
- Further research: A plan distinguishing all participants/key variables from outcome-specific completeness
- Conditions for verification: For Randomized/arm sizes, 0.05% key variables and outcome-specific denominators/flow, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Is 0.05% key-variable missingness the same as missing events/components?
- Application exceptions: Do not convert 0.05% to a person count or copy it to missingness rates for every endpoint/harm.
- Remaining uncertainty: Missingness by arm/endpoint/component, reasons for withdrawal/discontinuation and missing-data handling remain unverified.
- Referenced methods: M08 Table 8.2.a, M15 §15.3, M19 §19.1.2–19.2.4; design-specific adaptation is our own design; M08 §8.2.2, M15 §15.3.1; own application; M19 §19.1.2–19.2.4, M04 §4.6.3; own application
- Related sources: R01

### N19 · What separates original ITT from adherence/infection-conditioned estimands?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original records an ITT quotation for all randomized participants. Adherer/infection-conditioned analyses, actual exposure and model/adjustment/missing-data details are absent from the summary.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Estimands/analysis populations, adherence/missingness and covariate/conditional models remain unverified.
- Reason for missing information: Estimands/analysis populations, adherence/missingness and covariate/conditional models remain unverified.
- Required materials and conditions: All randomized adults in ITT, actual exposure/infected participants and serious-outcome estimand
- Materials to obtain first: SAP, analysis populations/models and exposure/denominator materials
- Further research: A plan distinguishing assigned prevention effects from serious-outcome effects among infected participants
- Conditions for verification: For All randomized adults in ITT, actual exposure/infected participants and serious-outcome estimand, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What separates original ITT from adherence/infection-conditioned estimands?
- Application exceptions: Do not repurpose a preventive assignment trial’s serious-outcome RR as treatment after infection or newly calculate absent denominators.
- Remaining uncertainty: Estimands/analysis populations, adherence/missingness and covariate/conditional models remain unverified.
- Referenced methods: M08 §8.2.2, M15 §15.3.1; own application; M03 §3.2.3, M08 §8.2.2–8.2.3; own application; M08 Table 8.2.a, M04 §4.6.3; own application
- Related sources: R01

### N20 · Were baseline vitamins/conditions, vaccination and concurrent exposures verified?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original specifies no routine daily supplements and the winter/combination-product scope. Baseline vitamin status, comorbidities/medications, vaccination/exposure and other supplement/treatment details are absent.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Baseline/changed conditions/medications, supplements/vaccination/infection exposures and arm differences remain unverified.
- Reason for missing information: Baseline/changed conditions/medications, supplements/vaccination/infection exposures and arm differences remain unverified.
- Required materials and conditions: Baseline/medications, other supplements/exposures and arm differences
- Materials to obtain first: Baseline/concurrent exposures and subgroup/protocol materials
- Further research: Research specifying population and shared exposures
- Conditions for verification: For Baseline/medications, other supplements/exposures and arm differences, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Were baseline vitamins/conditions, vaccination and concurrent exposures verified?
- Application exceptions: Do not add deficiency diagnoses, high-dose/single-ingredient effects or infection-prevention/treatment methods without original materials.
- Remaining uncertainty: Baseline/changed conditions/medications, supplements/vaccination/infection exposures and arm differences remain unverified.
- Referenced methods: M03 §3.2.3, M08 §8.2.2–8.2.3; internal application; M03 §3.2.1; detailed population conditions are internally designed; M19 §19.2.2–19.2.4 design considerations; detailed confounding records are internally designed
- Related sources: R01

### N21 · What are the original manufacturer/institution support and outside/diagnostics-author relationships?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original records Orkla Health AS funding/products/placebo, Oslo hospital/university support, KBH’s outside relationships with Olympic Seafood/Amgen/Sanofi, SMU’s with Olympic Seafood, and AS/KTK employment at Age Laboratories.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Original disclosures/supporters and current design/analysis/data-access role details remain unread.
- Reason for missing information: Original disclosures/supporters and current design/analysis/data-access role details remain unread.
- Required materials and conditions: Orkla supply/funding, Oslo support and disclosed relationships/employees
- Materials to obtain first: Original support/product-supply and author-relationship disclosures
- Further research: Specify funding and research-decision/analysis roles
- Conditions for verification: For Orkla supply/funding, Oslo support and disclosed relationships/employees, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the original manufacturer/institution support and outside/diagnostics-author relationships?
- Application exceptions: Do not combine diagnostics-company employees with manufacturer employees or turn manufacturer null reporting into independence/content-review certification or invalidation of the numbers.
- Remaining uncertainty: Original disclosures/supporters and current design/analysis/data-access role details remain unread.
- Referenced methods: Chamgap’s own independence/attribution conditions. The official methodological sections used in this pilot do not guarantee every detailed item; M08 §8.1–8.2.3; internal application
- Related sources: R01

### N22 · How are the same trial/people/composite components and related claims connected?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The existing single evidence/citation report links four outcomes, the same people/arms/period and related claims. Composite components, tests/symptoms/events are not added as new independent trials/participants.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Individual overlap/component relationships, related reports and unique-trial/participant totals remain unverified.
- Reason for missing information: Individual overlap/component relationships, related reports and unique-trial/participant totals remain unverified.
- Required materials and conditions: Single Brunvoll 2022 citation, four outcomes/arms/period and overlap
- Materials to obtain first: Trial/report identities and event/component/observation-unit data
- Further research: Records distinguishing reports from trial families/components
- Conditions for verification: For Single Brunvoll 2022 citation, four outcomes/arms/period and overlap, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How are the same trial/people/composite components and related claims connected?
- Application exceptions: One report or four outcomes do not certify the total independent-trial count or final independence count.
- Remaining uncertainty: Individual overlap/component relationships, related reports and unique-trial/participant totals remain unverified.
- Referenced methods: Study/report distinction in M04 §4.6.1–4.6.2; Cohort/outcome linkage is Chamgap application; M04 §4.6.1–4.6.2 and M15 §15.3.1; Chamgap application
- Related sources: R01

### N23 · What separates direct independent serious-outcome confirmation from the single-trial history?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Parent R1/I0 and the single large manufacturer-supported trial description are preserved as history. Other independent serious-outcome source materials were not newly searched for/acquired.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Populations/products/serious-outcome definitions and overlap/independence in separate direct reports remain unverified.
- Reason for missing information: Populations/products/serious-outcome definitions and overlap/independence in separate direct reports remain unverified.
- Required materials and conditions: Selected product/population and independent reports of the same serious outcome
- Materials to obtain first: Direct confirmation/trial-identity materials
- Further research: Separate research specifying the same product/population/serious-outcome definition
- Conditions for verification: For Selected product/population and independent reports of the same serious outcome, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What separates direct independent serious-outcome confirmation from the single-trial history?
- Application exceptions: Do not extend the original single trial into a current claim of no worldwide studies or count related outcomes as independent replication.
- Remaining uncertainty: Populations/products/serious-outcome definitions and overlap/independence in separate direct reports remain unverified.
- Referenced methods: Study/report distinction in M04 §4.6.1–4.6.2; Cohort/outcome linkage is Chamgap application; M04 §4.6.1–4.6.2 and M15 §15.3.1; Chamgap application
- Related sources: R01

### N24 · What separates a null combination product from deficiency/high-dose/single-ingredient effects?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original counterview/ad interpretation explicitly excludes deficiency treatment, high-dose vitamin D and omega-3 alone. Combination-product results are not turned into individual-ingredient conclusions.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Direct serious-outcome data for single/other exposures or deficient/at-risk populations remain unverified.
- Reason for missing information: Direct serious-outcome data for single/other exposures or deficient/at-risk populations remain unverified.
- Required materials and conditions: Original product versus deficiency treatment/high-dose vitamin D/n-3 alone
- Materials to obtain first: Exact ingredient/population/exposure-specific materials
- Further research: A plan separating the combination product from other questions
- Conditions for verification: For Original product versus deficiency treatment/high-dose vitamin D/n-3 alone, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What separates a null combination product from deficiency/high-dose/single-ingredient effects?
- Application exceptions: No new vitamin-use/deficiency-treatment guidance, product/ingredient recommendations or high-dose/treatment-replacement methods.
- Remaining uncertainty: Direct serious-outcome data for single/other exposures or deficient/at-risk populations remain unverified.
- Referenced methods: M03 §3.2.2–3.2.3; reverse-direction labels and testing adaptations are internally designed; M04 §4.6.1–4.6.2, M15 §15.3.1; internal application; M03 §3.2.1–3.2.4; dose/duration/effect-modification details are internally designed
- Related sources: R01

### N25 · Which serious, hospitalization/death, symptom/quality-of-life outcomes can be answered?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original serious-event totals and infection/questionnaire ARI are different outcomes. Direct values for individual hospitalization/death, quality of life/symptom severity or treating serious disease after infection are not separately available.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Clinical components/important outcomes and direct definitions/denominators/effects/periods remain unverified.
- Reason for missing information: Clinical components/important outcomes and direct definitions/denominators/effects/periods remain unverified.
- Required materials and conditions: Original serious-outcome name, individual/patient-important outcomes and treatment questions
- Materials to obtain first: Direct individual clinical/patient-important outcome materials
- Further research: Research distinguishing prevention/serious outcomes/treatment and component-specific estimands
- Conditions for verification: For Original serious-outcome name, individual/patient-important outcomes and treatment questions, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Which serious, hospitalization/death, symptom/quality-of-life outcomes can be answered?
- Application exceptions: Do not extend the original prevention null result to current serious-disease treatment failure or alternative-treatment selection.
- Remaining uncertainty: Clinical components/important outcomes and direct definitions/denominators/effects/periods remain unverified.
- Referenced methods: M03 §3.2.4; internally defined extension boundary; M03 §3.2.4, M15 §15.3.1–15.3.3; question-specific outcome adaptation is internally designed
- Related sources: R01

### N26 · What is the scope of summary reading, unread external materials and original links?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The entire preserved 2972 summary was read and saved for production. PubMed URL/NCT are original source links; external content/link access, clicks and tests were not performed.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Current verification of external serious-outcome definitions/methods/results and registration/plan/disclosure details remains incomplete.
- Reason for missing information: Current verification of external serious-outcome definitions/methods/results and registration/plan/disclosure details remains incomplete.
- Required materials and conditions: Entire summary, abstract/full text/registration/plans/disclosures
- Materials to obtain first: Acquired original materials and actual reading/addition events
- Further research: Records separating summaries/identities from new acquisition
- Conditions for verification: For Entire summary, abstract/full text/registration/plans/disclosures, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What is the scope of summary reading, unread external materials and original links?
- Application exceptions: Preserve absent DOI/PMCID and unread status; a URL/ID alone does not establish acquisition or access success/failure.
- Remaining uncertainty: Current verification of external serious-outcome definitions/methods/results and registration/plan/disclosure details remains incomplete.
- Referenced methods: M04 §4.5–4.6 material collection/selection principles; acquisition/reading separation and hyperlink specifications are internally designed; M04 §4.5, §4.6.3; limits of this material conversion follow the review scope and internal design
- Related sources: R01

### N27 · What are the bilingual text, dates/corrections, original axes/absences and history?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Bilingual text, original evidence date 2026-08-26 and empty corrections/deliberation are preserved. Parent B/H/R1/I0/E0/B0/C0, the true large-hard-endpoint-RCT indicator, two false indicators and empty grade-override reasons remain historical context. Separate classification fields and the primary-failed/secondary-positive indicator are unrecorded.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. External original quotations/translations and detailed registration/correction comparisons were not performed this time.
- Reason for missing information: External original quotations/translations and detailed registration/correction comparisons were not performed this time.
- Required materials and conditions: Parent D with 34 points, languages/dates/empty values and B0 quotations/axes
- Materials to obtain first: Original text, language-specific changes and date/correction events
- Further research: Separate original values/absences from new updates
- Conditions for verification: For Parent D with 34 points, languages/dates/empty values and B0 quotations/axes, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the bilingual text, dates/corrections, original axes/absences and history?
- Application exceptions: Do not inherit B0/prespecification/ITT quotations or cross-checking as current clinical-content review or independence certification.
- Remaining uncertainty: External original quotations/translations and detailed registration/correction comparisons were not performed this time.
- Referenced methods: M03 §3.1, §3.2.1–3.2.4 question-clarification principles; detailed splitting rules are internally designed; M04 §4.5, §4.6.3; current material-conversion limits follow review scope and internal design; Chamgap’s own independence/attribution conditions. The official methodological sections used in this pilot do not guarantee every detailed item
- Related sources: R01

### N28 · What was the original scope of harm collection and low-grade side effects?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original safety description states that only low-grade side effects were reported in both arms. All event definitions, collection/grading methods and serious/related-event/arm-count details are absent from the summary.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Harm collection/grading, all events and original causality/discontinuation tables remain unverified.
- Reason for missing information: Harm collection/grading, all events and original causality/discontinuation tables remain unverified.
- Required materials and conditions: Side-effect definitions/grading, collection/causality and arm events
- Materials to obtain first: Harm plans and event/grading/discontinuation materials
- Further research: Research specifying harm collection separately from efficacy
- Conditions for verification: For Side-effect definitions/grading, collection/causality and arm events, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What was the original scope of harm collection and low-grade side effects?
- Application exceptions: Do not turn the original low-grade-only description into zero side effects, long-term no harm or equivalent safety.
- Remaining uncertainty: Harm collection/grading, all events and original causality/discontinuation tables remain unverified.
- Referenced methods: M19 §19.1.2–19.2.4; Detailed distinctions are designed by CHAMGAP
- Related sources: R01

### N29 · Are side effects, serious COVID-19 and hospitalization/death categories distinguished?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The serious-COVID-19 RR and low-grade side-effect descriptions in both arms concern different outcomes. Serious-event counts 121/101 are not transferred to product-side-effect counts.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Definitions, causality/components and denominators for efficacy events/exposure harms remain unverified.
- Reason for missing information: Definitions, causality/components and denominators for efficacy events/exposure harms remain unverified.
- Required materials and conditions: Exposure harms, trial-efficacy serious outcomes and other-event causality
- Materials to obtain first: Efficacy/harm categories and causality/event materials
- Further research: A plan separating infection severity from exposure harms
- Conditions for verification: For Exposure harms, trial-efficacy serious outcomes and other-event causality, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Are side effects, serious COVID-19 and hospitalization/death categories distinguished?
- Application exceptions: Do not make new product-caused-harm or guaranteed-safety verdicts from RR 1.20 or low-grade descriptions.
- Remaining uncertainty: Definitions, causality/components and denominators for efficacy events/exposure harms remain unverified.
- Referenced methods: M19 §19.1.2–19.2.4; detailed discrimination is internally designed; Chamgap’s own interpretation boundaries. M19 principles are referenced; no official causality tool was run; M03 §3.2.4; internal extension boundaries
- Related sources: R01

### N30 · Are overall/arm-specific harm denominators the same as key-variable missingness?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Randomized arm sizes and key-variable missingness are described, but collection/denominators/exposure time and CI for each side effect are not separately available.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Harm denominators by arm/event/period and comparative effects/CI remain unverified.
- Reason for missing information: Harm denominators by arm/event/period and comparative effects/CI remain unverified.
- Required materials and conditions: 17,278/17,323, key-variable 0.05% and harm-observation populations
- Materials to obtain first: Harm flow and events/denominator tables by arm
- Further research: Research distinguishing efficacy analyses from harm-observation populations
- Conditions for verification: For 17,278/17,323, key-variable 0.05% and harm-observation populations, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Are overall/arm-specific harm denominators the same as key-variable missingness?
- Application exceptions: Do not copy all-participant/0.05% information into complete harm observation or calculate new incidence/differences/CI.
- Remaining uncertainty: Harm denominators by arm/event/period and comparative effects/CI remain unverified.
- Referenced methods: M19 §19.2.2–19.2.4, M03 §3.2.3; internal application; M19 §19.1.2–19.2.4; internal application
- Related sources: R01

### N31 · What is known about harm timing, after stopping, delayed and long-term observation?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original has a median 164 days of use and low-grade descriptions in both arms, but no side-effect timing or post-discontinuation/delayed/longer observation details.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Exposure/event timing and direct post-study/long-term harms remain unverified.
- Reason for missing information: Exposure/event timing and direct post-study/long-term harms remain unverified.
- Required materials and conditions: Original median 164 days and side-effect timing/exposure/follow-up
- Materials to obtain first: Exposure/harm timing and follow-up materials
- Further research: A plan distinguishing timing and delayed harms
- Conditions for verification: For Original median 164 days and side-effect timing/exposure/follow-up, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What is known about harm timing, after stopping, delayed and long-term observation?
- Application exceptions: Do not convert winter exposure into confirmed safety for all long-term/repeated use.
- Remaining uncertainty: Exposure/event timing and direct post-study/long-term harms remain unverified.
- Referenced methods: M19 §19.2 design-specific harm questions; temporal-relationship details are internally designed; M19 §19.1.2–19.2.4; internal application
- Related sources: R01

### N32 · What alternative causes involve combination product/placebo, medical history and medications?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original product is a combination and placebo flavour-matched corn oil. Detailed source materials attributing events to product/individual ingredients, baseline status or concurrent medications are absent.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Baseline/concurrent medications, actual exposure and event-specific causality/alternative causes remain unverified.
- Reason for missing information: Baseline/concurrent medications, actual exposure and event-specific causality/alternative causes remain unverified.
- Required materials and conditions: Vitamin/n-3 combination, shared exposures and event causality
- Materials to obtain first: Medical history/medications/exposure and event-causality records
- Further research: A harm plan distinguishing relevant exposure from alternative causes
- Conditions for verification: For Vitamin/n-3 combination, shared exposures and event causality, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What alternative causes involve combination product/placebo, medical history and medications?
- Application exceptions: Do not add unreported ingredients/invented harms or new medication/product stopping/substitution/management instructions.
- Remaining uncertainty: Baseline/concurrent medications, actual exposure and event-specific causality/alternative causes remain unverified.
- Referenced methods: M19 §19.2.2–19.2.4 design considerations; detailed confounding records are Chamgap design; M03 §3.2.3, M08 §8.2.2–8.2.3; Chamgap adaptation
- Related sources: R01

### N33 · Are key-variable missingness, serious-outcome confirmation and harm-related stopping distinguished?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original 0.05% key-variable missingness and ITT are preserved. Serious-event confirmation/component omissions, side-effect-related stopping and complete harm collection are not detailed.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Event/harm omissions, arm-specific stopping reasons/causality and handling remain unverified.
- Reason for missing information: Event/harm omissions, arm-specific stopping reasons/causality and handling remain unverified.
- Required materials and conditions: 0.05% missingness, event confirmation/collection and stopping reasons
- Materials to obtain first: Outcome/harm flow, omissions/discontinuation and SAP
- Further research: A plan distinguishing missing efficacy data from harm-related stopping
- Conditions for verification: For 0.05% missingness, event confirmation/collection and stopping reasons, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Are key-variable missingness, serious-outcome confirmation and harm-related stopping distinguished?
- Application exceptions: Do not declare zero omissions in all harms/components from a small key-variable missingness rate or fill unverified events with zero.
- Remaining uncertainty: Event/harm omissions, arm-specific stopping reasons/causality and handling remain unverified.
- Referenced methods: M19 §19.1.2–19.2.4, M04 §4.6.3; internal application; M08 §8.2.2, M15 §15.3.1; internal application
- Related sources: R01

### N34 · How do independent harm materials differ from the same trial/components/related claims?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The current list contains this large efficacy report. Separate original harm materials were not newly searched for/acquired; the same trial/people, composite components and related claims are not counted as independent harm trials.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Independent harm-material identities, population/product/exposure and overlap remain unverified.
- Reason for missing information: Independent harm-material identities, population/product/exposure and overlap remain unverified.
- Required materials and conditions: Separate safety-material identities and overlap in the same people/components
- Materials to obtain first: Separate harm/surveillance and event materials
- Further research: Records distinguishing the same trial from independent harms
- Conditions for verification: For Separate safety-material identities and overlap in the same people/components, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How do independent harm materials differ from the same trial/components/related claims?
- Application exceptions: Do not extend the current absence of a separate slot into a claim that all external safety materials are absent.
- Remaining uncertainty: Independent harm-material identities, population/product/exposure and overlap remain unverified.
- Referenced methods: M04 §§4.6.1–4.6.2; harm-material adaptation is Chamgap-designed; M04 §§4.6.1–4.6.2 distinction between studies and reports; cohort/outcome links are Chamgap adaptations
- Related sources: R01

### N35 · What are the boundaries for deficient/at-risk/vulnerable populations, current periods and long-term safety?

Verification status: Unverified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: The original limits scope to the tested dose/participants. It does not judge direct safety in deficient/high-risk/other-condition populations, current periods, long-term exposure or different products.
- Why unverified: Required direct materials were not verified within the current summary/unread-external-material scope. Direct events, medications and long-term follow-up by population/period/exposure remain unverified.
- Reason for missing information: Direct events, medications and long-term follow-up by population/period/exposure remain unverified.
- Required materials and conditions: Original winter product/population versus other risks/exposures/periods
- Materials to obtain first: Direct harms for at-risk/vulnerable populations and specific products/periods
- Further research: Research separating population and long-term safety questions
- Conditions for verification: For Original winter product/population versus other risks/exposures/periods, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: What are the boundaries for deficient/at-risk/vulnerable populations, current periods and long-term safety?
- Application exceptions: No new cod-liver-oil/vitamin/product-use, infection-prevention/COVID-19 management or serious-COVID-19 treatment guidance.
- Remaining uncertainty: Direct events, medications and long-term follow-up by population/period/exposure remain unverified.
- Referenced methods: M19 §19.1.2–19.2.4; internal application; M03 §3.2.1; detailed population conditions are internally designed; M03 §3.2.1–3.2.4; dose/duration/effect-modification details are internally designed
- Related sources: R01

### N36 · Are the causal scopes of null serious outcomes, other endpoints and good safety separated?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Original null serious outcomes, null findings for the other three endpoints, low-grade side effects and parent good safety are preserved separately. The serious-outcome interval/null result is not confirmed harm, equivalence/no-harm certification or separate hospitalization/death conclusions.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Direct component/comparative harms, causality/importance and long-term precision remain unverified.
- Reason for missing information: Direct component/comparative harms, causality/importance and long-term precision remain unverified.
- Required materials and conditions: Serious-outcome RR/interval, efficacy/harms and parent safety
- Materials to obtain first: Component-specific efficacy/harms and direct estimates/follow-up materials
- Further research: A plan separating different estimands/outcomes
- Conditions for verification: For Serious-outcome RR/interval, efficacy/harms and parent safety, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: Are the causal scopes of null serious outcomes, other endpoints and good safety separated?
- Application exceptions: Do not turn the original product null result into null effects for all vitamins/treatment replacement, guaranteed safety or a new grade.
- Remaining uncertainty: Direct component/comparative harms, causality/importance and long-term precision remain unverified.
- Referenced methods: Chamgap’s own interpretation boundaries. M19 principles are referenced; no official causality tool was run; M03 §3.2.4; internal extension boundaries; M15 §15.3.1–15.3.3; internal application
- Related sources: R01

### N37 · How are follow-up materials, historical candidates, versions and incomplete content review linked?

Verification status: Partly verified  
Reading scope: Summary read; external materials unread, access not attempted

- Current findings: Conditions were preserved/frozen before separate application. Candidate review-pending/production-eligibility labels remain historical records; current content/question-boundary review is incomplete. Zero new units and unrecorded confirmed independent totals are retained.
- Why unverified: Some original summary information is linked for production; this does not establish clinical verification/completed content review. Follow-up original materials, actual reading, changes, content review and independence decisions do not yet exist.
- Reason for missing information: Follow-up original materials, actual reading, changes, content review and independence decisions do not yet exist.
- Required materials and conditions: Preserved summary, conditions, units, denominators, components, original values and addition events
- Materials to obtain first: Additional original materials, before/after values, versions and change-decision records
- Further research: Research addressing direct gaps in the selected serious-COVID-19 question
- Conditions for verification: For Preserved summary, conditions, units, denominators, components, original values and addition events, separate original information from unverified details and boundaries on extension to infection/other respiratory outcomes, individual components/harms or current treatment.
- Why this condition is needed: Distinguish original product/population, serious outcome/components/denominators and unverified scope for this question: How are follow-up materials, historical candidates, versions and incomplete content review linked?
- Application exceptions: Do not invent current completed clinical-content review/publication from historical cross-checking or original production completion.
- Remaining uncertainty: Follow-up original materials, actual reading, changes, content review and independence decisions do not yet exist.
- Referenced methods: M03 §3.1, §3.2.1–3.2.4 question-clarification principles; detailed splitting rules are internally designed; M04 §4.6.3, M15 §15.3.1–15.3.3; status separation is internally designed; M04 §4.5, §4.6.3; current material-conversion limits follow review scope and internal design; M08 Table 8.2.a, M04 §4.6.3; internal application
- Related sources: R01

## Evidence and sources

### R01

Brunvoll SH, et al. Prevention of covid-19 and other acute respiratory infections with cod liver oil supplementation. BMJ. 2022;378:e071245. PMID: 36215222.

[PubMed](https://pubmed.ncbi.nlm.nih.gov/36215222/)

Materials actually read: Summary read; external materials unread, access not attempted  
Findings recorded in the summary: Original serious outcomes: 121 versus 101, RR 1.20 (0.87–1.65); the other three endpoints remain separate context in the full original evidence-result record.  
Record level: Selected original serious-outcome RR/adjusted 95% interval and null result. Exact serious composite/components, hospitalization/death/confirmation/risk denominators unverified. A preventive assignment trial is not repurposed as treatment effects after infection.  
Independent replication: Brunvoll 2022 links the same trial/citation, two assigned arms, four endpoints/serious components, people/period and parent/PCR/serious/other-respiratory claims. No new totals of independent trials/participants/events.

| Material | Public availability | Access status | Actually read | Notes |
|---|---|---|---|---|
| Stored summary | Local preserved summary | Summary read | Summary read | Only acquisition/reading of the entire parent summary. Original paper/registration or serious-component result tables were not acquired. |
| Abstract | External materials unread/needed | Unread; access not attempted | Not read | Only the original citation URL is linked. External content/access and link tests were not attempted. |
| Full paper | External materials unread/needed | Unread; access not attempted | Not read | Original DOI/PMCID not provided. No new acquisition/reading of the full text/content. |
| Registration material | External materials unread/needed | Unread; access not attempted | Not read | NCT04609423 and original posting/start/prospective descriptions preserved. Actual versions/content unread. |
| Protocol | External materials unread/needed | Unread; access not attempted | Not read | Original plans for product/population, serious composite/components/confirmation, risk denominators, four primary outcomes and harms are needed. Existence/publication status unverified. |
| Statistical analysis plan | External materials unread/needed | Unread; access not attempted | Not read | Original plans for ITT/at-risk populations, RR/intervals, fallback/adjustment and sparse-event/missingness/component analyses are needed. |
| Result tables and serious-component/denominator/harm materials | External materials unread/needed | Unread; access not attempted | Not read | Details needed for serious events 121/101/original RR, components/infected/at-risk populations, repetition/omissions and harms. No new event/CI calculation. |
| Funding/conflict-of-interest disclosures | External materials unread/needed | Unread; access not attempted | Not read | Original disclosures on Orkla/Oslo support, products/placebo, outside relationships/diagnostics-company employees and roles are currently unread. |

## Review criteria and methods

These are Chamgap's own application conditions, informed by the relevant sections of official methodological guidance. They do not constitute official assessment-tool certification or a new efficacy score.

- M03 [Cochrane Handbook 6.5 (2024), chapter updated 2023-08](https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-03) · §3.1, §3.2.1–3.2.3, MECIR C5/C7/C13 · Clearly record the question, eligibility conditions and reasons for changes, and distinguish variations in interventions. · Methodological principles stated in existing pilot materials and condition templates were referenced. The methodological text was not reviewed again in this work.
- M04 [Cochrane Handbook 6.5.1 (2025), chapter updated 2025-03](https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-04) · §4.5, §4.6.1–4.6.3, MECIR C42 · Distinguish studies from reports and link them; do not omit a study solely because results are unreported. · Methodological principles stated in existing pilot materials and condition templates were referenced. The methodological text was not reviewed again in this work.
- M08 [Cochrane Handbook 6.5 (2024), chapter updated 2019-10](https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-08) · §8.1–8.2.3, Table 8.2.a · Define the outcome and effect of interest, then examine randomization, deviations, missing data, measurement and selective reporting. · Methodological principles stated in existing pilot materials and condition templates were referenced. The methodological text was not reviewed again in this work.
- M15 [Cochrane Handbook 6.5 (2024), chapter updated 2023-08](https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-15) · §15.2.4, §15.3.1–15.3.3 · Distinguish effect estimates, intervals, importance and applicability. Sample size alone does not determine precision. · Methodological principles stated in existing pilot materials and condition templates were referenced. The methodological text was not reviewed again in this work.
- M19 [Cochrane Handbook 6.5 (2024), chapter updated 2019-10](https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-19) · §19.1.2, §19.2.1–19.2.4 · Harm questions may require different designs, populations and follow-up from efficacy questions. Case reports do not establish incidence rates. · Methodological principles stated in existing pilot materials and condition templates were referenced. The methodological text was not reviewed again in this work.

## What the statuses mean

- Met: The original content has been reviewed as meeting the conditions. This status is not used in this preparation.
- Partly verified: Some information in the stored summary was linked during preparation; clinical verification or review is not complete.
- Unverified: Required direct values, definitions or materials have not been established within the current storage and reading scope. This does not mean zero effect, no papers or failed access.
- Review incomplete: Review of existing content or actual review incomplete.
- Not reported: Used only when original materials were actually read and the outcome was judged unreported. Not used for external materials unread in this work.
- Inaccessible: Used only when an actual access attempt has a recorded failure. Not used for access that was not attempted in this work.
- Insufficient evidence for the conditions: Indicates insufficient direct materials for the relevant scope or conditions; it is not a new grade.
- Not applicable: Used when the reason it does not apply to the original question is stated.
- Conflicting data: Retains the scope of conflicting statements in original materials; it is not an arbitrary reassessment.

## Change history

2026-10-14 · Public page/materials 1.0. Public-facing pages and materials were prepared from the existing 37 items. No new clinical search, verification-status changes or scoring.