{ "schema_version": "chamgap-public-evidence-check-1.0", "public_id": "v1585-s0", "verdict_number": "1585", "title": "Vitamin C × HbA1c in type 2 diabetes", "view_version": "1.0", "view_created_date": "2026-10-07", "criteria_version": "1.1", "criteria_date": "2026-10-04", "review_date": "2026-10-04", "legacy_evidence_date": "2026-07-24", "review_scope": { "materials_read": "Existing review summaries and the relevant methodology sections", "clinical_papers_directly_read": false, "new_clinical_search": false, "limitation": "This does not establish that no research exists worldwide. Research beyond the stored materials, and the public availability and accessibility of clinical papers, require further searching and checking.", "date_meaning": "This is the date the stored materials were checked, not the date of a new search of the clinical literature." }, "claim_context": { "population": "People with type 2 diabetes; trial-specific age ranges, diagnostic criteria and baseline characteristics are unverified", "intervention": "Assessment scope: oral vitamin C tablets or capsules. The chemical form and whether each trial used a single ingredient or a combination remain unverified", "dose": "The overall review covered 200–3,000 mg/day. Doses in the individual HbA1c trials are unverified", "comparator": "Required comparison: vitamin C added to shared background treatment versus placebo or no added vitamin C. This defines Chamgap's question; the actual comparators in the original trials are unverified", "endpoint": "Difference in HbA1c versus the comparator, in percentage points. The exact group order, final values versus changes from baseline, and adjustment are unverified", "duration": "The overall review covered 2 weeks–1 year, mostly less than 6 months. Trial-specific HbA1c durations and an appropriate minimum duration are unverified or undetermined", "excluded_extensions": "Fasting or post-meal glucose, complications or mortality, replacing medication, optimal doses and efficacy in special populations are separate questions" }, "requirements": [ { "item_id": "N01", "question_type": "Efficacy and target population", "question": "Which population with type 2 diabetes does the effect apply to?", "needed": "Obtain trial-specific diagnoses, ages, baseline HbA1c, disease duration, care settings and inclusion/exclusion criteria", "role": "Required", "role_reason": "The broad label 'type 2 diabetes' does not establish that the target populations are equivalent.", "application_exception": "For mixed populations, separate results or documentation of the population mix and indirectness are acceptable. Other types of diabetes require a separate question.", "criterion": "Identify each trial's population, diagnoses and baseline characteristics, and explain matches or differences with the selected claim using locations in the original paper", "basis": "M03 §3.2.1", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Prespecified stratified comparative trials including populations with different representativeness; first obtain tables of the included trials' characteristics", "current_reports": [ "S01", "S02", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary identifies the population as people with type 2 diabetes. Trial-specific diagnoses, ages, baseline HbA1c and settings could not be verified from that summary.", "condition_status": "Partly verified", "status_reason": "The named target population is verified, but trial-specific conditions needed to establish population alignment are unverified.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Who the findings apply to, and differences between deficient and non-deficient participants", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N02", "question_type": "Ingredient, formulation and route", "question": "What was actually administered?", "needed": "Verify the chemical form of vitamin C, single ingredient versus combination, tablet versus capsule, oral route, product and content", "role": "Required", "role_reason": "Needed to avoid attributing effects from other formulations, routes or added ingredients to oral vitamin C.", "application_exception": "Combination products may contribute if shared ingredients and between-group differences can be separated. Intravenous preparations and foods require separate comparisons.", "criterion": "Verify each trial's actual ingredients, route, formulation and control ingredients, while retaining unverified details as unverified", "basis": "M03 §3.2.2–3.2.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Obtain product analyses and manufacturing/content records; superiority of a particular formulation requires a direct comparative trial", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary names oral tablets or capsules and states that superiority of a specific formulation has not been established. Each trial's chemical form, combination ingredients and product remain unverified.", "condition_status": "Partly verified", "status_reason": "The route specified in the claim is verified, but original materials needed to match each trial's formulation and ingredients are insufficient.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "The contribution of vitamin C alone and equivalence between products", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N03", "question_type": "Dose and exposure", "question": "Which dose is the efficacy question about?", "needed": "Distinguish daily prescribed dose, dosing frequency, actual intake, adherence, baseline diet and vitamin C status", "role": "Required", "role_reason": "If nominal dose differs from actual exposure, applicability and dose interpretation change.", "application_exception": "When baseline deficiency information is absent, retain studies of the overall effect and leave only deficiency-specific applicability unverified.", "criterion": "Link dose, actual exposure, verification methods and duration for each trial contributing to the HbA1c analysis", "basis": "M03 §3.2.2; M15 §15.2.4", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Comparative trials with prespecified exposure measurement and adherence tracking; effect-modification analyses by baseline status", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The overall review's dose range of 200–3,000 mg/day is preserved. Dose, adherence, diet and baseline vitamin C status in each HbA1c trial remain unverified.", "condition_status": "Partly verified", "status_reason": "Do not assume that the overall review's range represents identical conditions in the trials contributing to HbA1c.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "The exposure at which the results were observed", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N04", "question_type": "Comparison", "question": "Lower than what comparator?", "needed": "Specify the actual placebo, no-treatment, usual-care or active comparator and fix the group order used to calculate the effect", "role": "Required", "role_reason": "A different comparator means a different question, even when the numerical result is the same.", "application_exception": "Retain active-comparator results, but present them separately from the main question comparing against no added vitamin C.", "criterion": "Verify each trial's control conditions, group order and rationale for inclusion in the synthesis", "basis": "M03 §3.2.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials explicitly describing placebo/no added vitamin C and shared treatment, or original descriptions of existing comparators", "current_reports": [ "S01", "S02", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored review summary does not provide each trial's comparator details or the group order used to calculate effects. The existing explanation describes a between-group mean difference, but original trial and synthesis tables were not checked.", "condition_status": "Unverified", "status_reason": "The actual comparison is not established because original descriptions of the comparison were not obtained.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Mixing placebo, usual-care and active comparisons", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N05", "question_type": "Concomitant treatment", "question": "Can the contribution of added vitamin C be separated?", "needed": "Verify shared diabetes treatment, medication adjustments, diet, exercise, other supplements and changes in both groups", "role": "Required", "role_reason": "Check whether differences in other treatments contribute to the observed difference.", "application_exception": "Do not require completely identical treatment. If treatment changes, review balance, analysis and alignment with the effect of interest.", "criterion": "Link baseline and follow-up concomitant treatments/changes, between-group differences and how they were handled", "basis": "M03 §3.2.3; M08 §8.2.2–8.2.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Add-on treatment trials with prespecified records of shared treatment, adjustment rules and rescue treatment", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "Each group's concomitant diabetes treatment, medication adjustments, diet/exercise and other supplements could not be verified from the stored review summary.", "condition_status": "Unverified", "status_reason": "General advice against replacing medication is not an experimental record establishing identical treatment in both groups.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "The contribution of treatment differences other than vitamin C", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N06", "question_type": "Efficacy study design", "question": "Can intervention effects be distinguished from chance and confounding?", "needed": "Randomization methods, allocation concealment, baseline balance and result-specific risk-of-bias information from comparative trials", "role": "Required (causal efficacy)", "role_reason": "The label 'randomized' alone does not resolve risk-of-bias concerns.", "application_exception": "Also record and use non-randomized studies as supporting evidence. Judgments must fit parallel, crossover or cluster designs. A formal RoB 2 assessment is outside this review's scope.", "criterion": "Obtain original evidence of the actual design, randomization/concealment and relevant baseline differences, and discuss their effect on results", "basis": "M08 §8.1–8.2.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Preregistered comparative trials with appropriate randomization, concealment and result analyses; first obtain the original methods", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The reports are labelled systematic reviews/meta-analyses of RCTs. Randomization, concealment and baseline balance in the original trials are unverified.", "condition_status": "Partly verified", "status_reason": "Distinguish the existence of a study-design label from a result-specific assessment of bias.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Differences arising during allocation", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N07", "question_type": "Effect of interest and analysis", "question": "Is this the effect of assignment or the effect of adhering to treatment?", "needed": "Distinguish ITT/PP, analysis populations, adjustment variables, final values versus changes, and handling of crossover/cluster designs", "role": "Required", "role_reason": "Needed to avoid combining different effects and analyses as if they were the same result.", "application_exception": "Crossover/cluster requirements are marked not applicable or handled separately only after the design is verified.", "criterion": "Verify agreement or differences between the effect of interest, the actual analysis and the effect used in the synthesis", "basis": "M08 §8.2.2; M15 §15.3.1", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Comparative trials or reanalysis materials providing a prespecified analysis plan and necessary correlation, period and cluster information", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary records a mean reduction and a WMD. Mixing final values with changes, adjustment, ITT/PP, and parallel/crossover/cluster designs remain unverified.", "condition_status": "Unverified", "status_reason": "Do not reinterpret −0.54 as a within-group change.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Alignment between the effect of interest and the actual analysis", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N08", "question_type": "Missing data", "question": "Who was lost to follow-up?", "needed": "Group-specific numbers allocated, completing follow-up, measured and analysed; reasons for dropout, handling of missing data and sensitivity analyses", "role": "Required", "role_reason": "Review the possibility that missing data changed the observed result.", "application_exception": "Do not use an arbitrary universal dropout-rate threshold. Examine causes of missingness and their relationship to the outcome.", "criterion": "Link outcome- and time-specific denominators, missingness, handling methods and results under different assumptions", "basis": "M08 Table 8.2.a", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials tracking dropout causes and follow-up with sensitivity analyses under different assumptions; obtain existing flow diagrams and analysis materials", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "1,133/1,247 are recorded as outcome-specific synthesis samples for HbA1c. Group-specific allocation/completion/analysis numbers and dropout reasons are not recorded at this location.", "condition_status": "Unverified", "status_reason": "Not reported in the stored summary. This does not establish that the full paper failed to report it.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "How much missing data and dropout could alter the result", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N09", "question_type": "Measured outcome", "question": "Are the HbA1c measurements comparable?", "needed": "Verify HbA1c assay methods, units, blood-sampling times, assay interference/red-cell limitations and assessor blinding", "role": "Required", "role_reason": "Needed to distinguish measurement differences from actual changes.", "application_exception": "Do not generalize glucose-meter interference to all HbA1c assays. Review each assay method separately.", "criterion": "Verify each trial's HbA1c methods, units, visits and measurement limitations. Distinguish percentage points from relative percentages", "basis": "M08 Table 8.2.a; M03 §3.2.4", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials reporting assay methods, interference validation and blood-sampling rules; analytical method comparisons where needed", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "HbA1c units in percentage points and cautions about glucose-meter/some assay interference are recorded. Trial-specific HbA1c assays, blinding and interference remain unverified.", "condition_status": "Partly verified", "status_reason": "A glucose-meter caution is not evidence that the HbA1c results are erroneous.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Distinguishing differences in measurement methods from actual changes", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N10", "question_type": "Duration", "question": "Does the observation period fit the question?", "needed": "Record treatment, measurement and follow-up periods separately, with evidence supporting the time frame used to interpret HbA1c changes", "role": "Required", "role_reason": "Short-term observation and sustained effects are different questions.", "application_exception": "Do not adopt an arbitrary minimum number of weeks. An appropriate duration is undetermined from these materials alone.", "criterion": "Specify the timeline of each contributing trial, the questions that timeline can answer and its limitations", "basis": "M03 §3.2.2–3.2.4", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials scheduling visits based on the outcome's time characteristics; official original assay references supporting duration criteria require follow-up checking", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary describes an overall review range of 2 weeks–1 year, mostly less than 6 months. Durations of the individual trials contributing to HbA1c are unverified.", "condition_status": "Partly verified", "status_reason": "Do not transfer the overall review's duration range to each individual HbA1c trial.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Outcome timing and criteria for an appropriate follow-up period", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N11", "question_type": "Result definition", "question": "Exactly what difference was observed?", "needed": "Link effect estimates, measures, units, group order, confidence intervals, time points, denominators and adjustment to original materials", "role": "Required", "role_reason": "Within-group changes, between-group differences and pooled estimates are different results.", "application_exception": "Retain synthesis summaries as results, while distinguishing them from direct results of original trials.", "criterion": "Make analysis attribution traceable so that distinct results are not mistaken for the same effect", "basis": "M15 §15.3.1–15.3.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Obtain original trial result tables/supplements and recheck the original numbers; define the unit of analysis before a new synthesis", "current_reports": [ "S01", "S02", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "S01 −0.54 percentage points (95% CI −0.90 to −0.17) and S03 WMD −0.51 percentage points (95% CI −0.81 to −0.20) are preserved. S02 restates −0.54.", "condition_status": "Partly verified", "status_reason": "The stored locations of values and units are verified, but group order, analysis/time points and attribution to original paper tables are unverified.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Definition of between-group results, synthesis models and included values", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N12", "question_type": "Precision and sample size", "question": "What conclusions does the interval allow?", "needed": "Link outcome-specific samples, variance and effect intervals to a justified important difference", "role": "Required", "role_reason": "Study or participant counts alone cannot establish sufficiency, and statistical significance does not establish efficacy.", "application_exception": "If a clinical-importance threshold is absent, leave it undetermined. Do not impose an arbitrary minimum sample or trial count.", "criterion": "Compare the effects the CI excludes or allows—important effects, small effects or no difference—with an evidence-based threshold", "basis": "M15 §15.3.1–15.3.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials with sample sizes based on important-difference, variance and dropout assumptions; first agree on the threshold and obtain existing variance information", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "Outcome-specific HbA1c CIs and samples are available. The stored summary mentions some clinical-relevance thresholds, but contains no verified numerical threshold or source supporting its application.", "condition_status": "Partly verified", "status_reason": "Precision sufficiency is not judged because no new importance threshold has been invented.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Whether an important difference is excluded or allowed, and assumptions used to design the sample", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N13", "question_type": "Selective reporting", "question": "Can all prespecified results be examined?", "needed": "Compare registration, protocol and analysis plans with reported HbA1c time points, analyses and reasons for changes", "role": "Required", "role_reason": "Examine whether an analysis was selected because its results were favourable.", "application_exception": "Retain the study's existence and results even if registration is absent or private. Do not turn an unverified status into confirmed selective reporting.", "criterion": "Compare prespecified and reported outcomes, analyses and time points, explaining changes or why comparison is impossible", "basis": "M08 Table 8.2.a; M04 §4.6.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Trials publishing preregistration, protocols/SAPs and all results, or retrieval of existing registrations/supplements", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "Bibliographic records in the stored materials mainly concern reviews. Original trial registrations, protocols, SAPs and comparisons of prespecified versus reported HbA1c analyses were not verified from these materials.", "condition_status": "Review incomplete", "status_reason": "Registrations/plans were neither obtained nor searched in this review. Lack of registration or selective reporting is not established.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Whether outcomes, analyses and time points were prespecified", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N14", "question_type": "Study families", "question": "Do three review papers represent independent replication?", "needed": "Link original trials, registrations, related reports and review inclusion tables into study families, recording overlap", "role": "Required", "role_reason": "The same participants or trial must not be counted more than once.", "application_exception": "Retain unresolved study families under provisional identities. Unique trial and participant counts remain undetermined.", "criterion": "Trace report → original trial → inclusion in each review, and identify matching or unresolved identities", "basis": "M04 §4.6.1–4.6.2", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Obtain included-trial/registration lists and compare duplicates; then conduct independent replication in a different recruited population", "current_reports": [ "S01", "S02", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "Bibliographic identities exist for three review reports. The acquired summaries contain no original-trial/related-report family table or review-overlap table.", "condition_status": "Unverified", "status_reason": "Do not add original trial counts as 16+18 or participants as 1,133+1,247.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Unique trials/participants and independent replication", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N15", "question_type": "Inconsistency and replication", "question": "Are results consistent under different conditions?", "needed": "Record trial-specific opposing, no-difference and positive results, condition differences, heterogeneity and prespecified subgroups", "role": "Required (overall applicability)", "role_reason": "One pooled average does not guarantee results in every population and setting.", "application_exception": "Between-study comparison may be not applicable for a single study family, but NA is not assigned here because study families remain unresolved.", "criterion": "Preserve the distribution of unique trial results, explanations of condition differences/inconsistency and uncertainty", "basis": "M03 §3.2.1; M15 §15.3.1", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Independent multicentre replication under standardized conditions; test prespecified hypotheses about baseline status and dose", "current_reports": [ "S01", "S02", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "S03 I²=90.4% is recorded in the stored summary. Trial-specific opposing/no-difference/positive HbA1c values are unverified. Non-significant results and limitations for other outcomes are also preserved in the original record.", "condition_status": "Partly verified", "status_reason": "Similar directions of two pooled averages do not verify independent replication or consistent effects in individual trials.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Causes of inconsistency, locations of opposing results and reproducibility", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N16", "question_type": "Dose question", "question": "Is a higher dose better?", "needed": "Direct dose comparisons, exposure/dose response, and joint observation of benefits and harms", "role": "Additional (required for dose selection)", "role_reason": "Dose differences across trials may be confounded by differences in populations and durations.", "application_exception": "The main HbA1c-change question can be retained without claiming dose superiority.", "criterion": "Dose differences within the same comparison framework, or dose-response evidence explicitly describing confounding limitations", "basis": "M03 §3.2.2; Chamgap's own dose-study design proposal", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Randomized dose comparisons using the same formulation and shared treatment. Determine sample sizes and doses after reviewing the evidence", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary states that a standard diabetes dose and superiority of particular formulations are undetermined. Direct dose-comparison results could not be verified from the stored summary.", "condition_status": "Unverified", "status_reason": "Further searching is needed to establish whether dose studies exist beyond these stored materials.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Dose selection considering benefits and harms together", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N17", "question_type": "Persistence", "question": "Does the effect persist long term or after stopping treatment?", "needed": "Verify long-term exposure, post-treatment visits, medication changes and HbA1c trajectories", "role": "Additional (required for persistence claims)", "role_reason": "A change at the end of treatment differs from a sustained effect.", "application_exception": "Do not remove short-term studies as ineligible. Leave persistence separately unverified.", "criterion": "Long-term comparative results with timelines, treatment continuation/discontinuation and loss to follow-up", "basis": "M03 §3.2.2; Chamgap's own persistence-study design proposal", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Comparative trials/follow-up studies with prespecified long-term extensions and post-treatment follow-up. Duration is undetermined", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The limitation that most studies are short term is preserved. Post-treatment persistence, long-term medication changes and fixed extension follow-up results are unverified in the acquired summaries.", "condition_status": "Unverified", "status_reason": "A duration range including 1 year does not by itself verify long-term persistence or persistence after stopping treatment.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Long-term maintenance and the effects of treatment changes", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N18", "question_type": "Safety", "question": "What harms were observed in the same population at the same dose?", "needed": "Verify group-specific harm definitions, collection methods, event/person counts, denominators, exposure periods and discontinuations", "role": "Required (harm question)", "role_reason": "Non-reporting cannot be interpreted as zero events or established safety.", "application_exception": "Retain efficacy results even when harms are not reported in an efficacy study. Present safety separately.", "criterion": "Distinguish events in both groups, observation periods, denominators, collection methods and non-reporting", "basis": "M19 §19.1.2–19.2.4", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Obtain comparative trials/safety reports documenting both prespecified harm collection and unanticipated harms", "current_reports": [ "S02", "S04" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The existing summary records limited safety data and gastrointestinal/oxalate cautions. Group-specific event counts, denominators and durations in this population at these doses are unverified.", "condition_status": "Partly verified", "status_reason": "Separate general cautions from events observed in trials. Do not record non-reporting as zero events.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Actual harm frequency and collection methods", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N19", "question_type": "Long-term/rare harms and special populations", "question": "What about harms outside short trials and vulnerable populations?", "needed": "Exposure, comparisons, occurrence and long-term harm data in existing caution groups, including people with kidney disease/stone histories or iron overload", "role": "Required (applicable harm assessment)", "role_reason": "The restricted populations and durations of efficacy trials may not capture rare harms.", "application_exception": "Also preserve observational studies, registries and case signals. Without control of confounding and denominators, do not establish incidence rates or causality.", "criterion": "Verify design-specific event definitions, exposure, comparisons/confounding, denominators, durations and population-applicability limitations", "basis": "M19 §19.1.2, §19.2.2–19.2.4", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Long-term cohorts/registries with denominators, exposure and appropriate comparators; special-population data require separate searching", "current_reports": [ "S04" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary cautions about kidney disease/stone histories and iron overload. Long-term exposure and absolute risks in specific populations are unverified in these materials.", "condition_status": "Unverified", "status_reason": "The existence of a caution group is not a numerical risk estimate or evidence of no efficacy.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Long-term and rare harms, and risks in vulnerable populations", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N20", "question_type": "Applicability to subgroups", "question": "Is the effect greater in deficient participants or particular populations?", "needed": "Baseline vitamin C, HbA1c, medication/disease characteristics, prespecified effect-modification hypotheses and interactions", "role": "Additional (required for subgroup claims)", "role_reason": "Needed to avoid extending an overall average to a particular population.", "application_exception": "Pregnancy, children and other types of diabetes are not automatic extensions of this claim.", "criterion": "Verify prespecified hypotheses and definitions, subgroup samples/estimates, interactions and precision", "basis": "M03 §3.2.1; Chamgap's own effect-modification proposal", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Prespecified stratified trials or agreed individual-participant-data analyses. Label subgroups not defined in advance as exploratory", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The stored summary describes possible differences by low baseline vitamin C, dose and duration. Prespecified subgroup and interaction evidence is unverified.", "condition_status": "Unverified", "status_reason": "Do not upgrade a hypothesis to verified efficacy in a particular population.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Effect differences by deficiency, disease severity and special population", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N21", "question_type": "Search, access and publication status", "question": "What might the current record have missed?", "needed": "Search scope/dates, inclusion/exclusion, registrations/unpublished studies, corrections/retractions, and material-specific access/reading histories", "role": "Required (claims about the current overall evidence)", "role_reason": "The existence of a stored summary does not mean the entire current literature has been checked.", "application_exception": "No new clinical search was performed. Only the currently preserved scope applies.", "criterion": "Record the scope in which evidence is absent or unverified, by date and material type", "basis": "M04 §4.5, §4.6.3", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "In an authorized follow-up, search and select new literature/registrations/publication-status information and record access. This was not performed here", "current_reports": [ "S01", "S02", "S03", "S04" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The existing evidence cut-off field is 2026-07-24. On 2026-10-04, only stored materials and methodology were checked; no new clinical search or correction/retraction checks were performed.", "condition_status": "Review incomplete", "status_reason": "This case did not review the entire current clinical literature or its latest status. The existence and accessibility of materials beyond papers are also unverified.", "missingness": "Not recorded in the stored summary / review of original papers incomplete. This does not establish that the original papers failed to report the information or were inaccessible", "uncertainty": "Missing/unpublished/new studies, publication status and access scope", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." }, { "item_id": "N22", "question_type": "Clinical outcomes and scope boundaries", "question": "Does a change in HbA1c directly establish benefits for complications?", "needed": "Questions about complications, quality of life or mortality require separate comparative results, events and durations for those outcomes", "role": "Additional (required for extended claims)", "role_reason": "A boundary distinguishing questions about biomarkers from questions about clinical events.", "application_exception": "Do not require clinical-event trials as a mandatory condition for the selected question about numerical HbA1c change itself.", "criterion": "Identify the separate clinical question/outcome and direct evidence. Do not automatically extend HbA1c findings", "basis": "M03 §3.2.4; Chamgap's own boundary for extended claims", "condition_origin": "Chamgap's own application conditions and proposals", "proposed_research": "Long-term comparative trials based on clinical events, with a separately defined question. This is not a new claim or search in this case", "current_reports": [ "S01", "S03" ], "existence": "Stored bibliographic records and summaries of relevant reports exist; the identities of eligible original trials are unverified", "acquired_read": "Stored existing review summaries were read on 2026-10-04. Full papers, supplements, registrations, plans and original data were not read.", "observation": "The selected question concerns numerical HbA1c change. Existing separate subclaims describe benefits for complications/mortality as unestablished. Those findings were not reassessed here.", "condition_status": "Not applicable (as a mandatory condition for the selected outcome)", "status_reason": "Clinical-event trials are not required for the HbA1c question itself. Extending to benefits for complications requires separate conditions.", "missingness": "Not applicable with an explicit application exception", "uncertainty": "Questions about complications, mortality and quality of life are outside this scope and require further searching", "review_date": "2026-10-04", "reading_status": "Full text not read · Stored summary read", "additional_material": "First obtain and compare the necessary original materials, including existing papers, supplements and tables of included trials." } ], "reports": [ { "report_id": "S01", "title": "Mason SA, Keske MA, Wadley GD. Effects of Vitamin C Supplementation on Glycemic Control and Cardiovascular Risk Factors in People With Type 2 Diabetes: A GRADE-Assessed Systematic Review and Meta-analysis of Randomized Controlled Trials. Diabetes Care. 2021;44(2):618-630. PMID: 33472962. DOI: 10.2337/dc20-1893.", "url": "https://pubmed.ncbi.nlm.nih.gov/33472962/", "report_type": "Systematic review and meta-analysis of randomized trials with GRADE assessment", "existence": "Stored materials contain bibliographic and result records; publication status was not checked live in this review", "acquired_read": "Relevant sections and citation records in the existing review summary were read", "study_family": "Only the review report's identity is established. Included original-trial families and overlap are unverified", "independent_replication": "Unverified; counts of review papers and original trials do not represent the number of independent replications", "observed_result": "Stored summary: HbA1c analysis of 16 RCTs and 1,133 participants, −0.54 percentage points (95% CI −0.90 to −0.17).", "result_level": "Values reported in a stored summary, not directly verified against the original paper", "source_evidence_date": "2026-07-24", "materials": [ { "material_type": "Abstract", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Full text", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Supplement", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Protocol", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Registration", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Original data", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" } ], "links": [ { "label": "Publisher", "url": "https://doi.org/10.2337/dc20-1893" }, { "label": "PubMed", "url": "https://pubmed.ncbi.nlm.nih.gov/33472962/" } ] }, { "report_id": "S02", "title": "Fong C, Alesi S, Mousa A, et al. Efficacy and Safety of Nutrient Supplements for Glycaemic Control and Insulin Resistance in Type 2 Diabetes: An Umbrella Review and Hierarchical Evidence Synthesis. Nutrients. 2022;14(11):2295. PMID: 35684094. PMCID: PMC9182772. DOI: 10.3390/nu14112295.", "url": "https://pubmed.ncbi.nlm.nih.gov/35684094/", "report_type": "Umbrella review and hierarchical evidence synthesis of nutritional-supplement meta-analyses", "existence": "Stored materials contain bibliographic and result records; publication status was not checked live in this review", "acquired_read": "Relevant sections and citation records in the existing review summary were read", "study_family": "Only the review report's identity is established. Included original-trial families and overlap are unverified", "independent_replication": "Unverified; counts of review papers and original trials do not represent the number of independent replications", "observed_result": "Stored summary: restates the HbA1c mean difference of −0.54 percentage points. Not counted as a new independent trial result.", "result_level": "Values reported in a stored summary, not directly verified against the original paper", "source_evidence_date": "2026-07-24", "materials": [ { "material_type": "Abstract", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Full text", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "PMCID PMC9182772 appears in S02's stored bibliographic record. Public full-text availability or successful access was not verified in this review." }, { "material_type": "Supplement", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Protocol", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Registration", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Original data", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" } ], "links": [ { "label": "Publisher", "url": "https://doi.org/10.3390/nu14112295" }, { "label": "PMC", "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC9182772/" }, { "label": "PubMed", "url": "https://pubmed.ncbi.nlm.nih.gov/35684094/" } ] }, { "report_id": "S03", "title": "Nosratabadi S, Ashtary-Larky D, Hosseini F, et al. The effects of vitamin C supplementation on glycemic control in patients with type 2 diabetes: A systematic review and meta-analysis. Diabetes Metab Syndr. 2023;17(8):102824. PMID: 37523928. DOI: 10.1016/j.dsx.2023.102824.", "url": "https://pubmed.ncbi.nlm.nih.gov/37523928/", "report_type": "Updated systematic review and meta-analysis of randomized trials", "existence": "Stored materials contain bibliographic and result records; publication status was not checked live in this review", "acquired_read": "Relevant sections and citation records in the existing review summary were read", "study_family": "Only the review report's identity is established. Included original-trial families and overlap are unverified", "independent_replication": "Unverified; counts of review papers and original trials do not represent the number of independent replications", "observed_result": "Stored summary: HbA1c analysis of 18 RCTs and 1,247 participants, WMD −0.51 percentage points (95% CI −0.81 to −0.20), I² 90.4%.", "result_level": "Values reported in a stored summary, not directly verified against the original paper", "source_evidence_date": "2026-07-24", "materials": [ { "material_type": "Abstract", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Full text", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Supplement", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Protocol", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Registration", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" }, { "material_type": "Original data", "public_status": "Unverified (no web access/search attempted in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Not read", "as_of": "2026-10-04", "qualification": "The existing review summary was read, rather than the paper itself" } ], "links": [ { "label": "Publisher", "url": "https://doi.org/10.1016/j.dsx.2023.102824" }, { "label": "PubMed", "url": "https://pubmed.ncbi.nlm.nih.gov/37523928/" } ] }, { "report_id": "S04", "title": "National Institutes of Health, Office of Dietary Supplements. Vitamin C: Fact Sheet for Health Professionals. Updated July 31, 2025. PMID: none. DOI: none.", "url": "https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/", "report_type": "Existing citation record of official safety information", "existence": "Existing bibliographic records/caution text are present; the current web source is unverified", "acquired_read": "Only citations and safety guidance in the existing review summary were read", "study_family": "Not a trial", "independent_replication": "Not applicable: not an efficacy replication trial", "observed_result": "The existing stored summary records cautions about gastrointestinal effects, oxalate/stones, iron overload and meter interference. These are not event-count/incidence data for this population.", "result_level": "Preserved general caution information; not a new safety assessment", "source_evidence_date": "2026-07-24", "materials": [ { "material_type": "Full web fact sheet", "public_status": "Unverified (original source not accessed in this review)", "access_status": "Access not attempted", "acquired": false, "actually_read": "Preserved citations/summary only", "as_of": "2026-10-04" } ], "links": [ { "label": "Official source", "url": "https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/" } ] } ], "method_sources": [ { "id": "M03", "version": "Cochrane Handbook 6.5 (2024), chapter updated 2023-08", "url": "https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-03", "section": "§3.1, §3.2.1–3.2.3, MECIR C5/C7/C13", "official_principle": "Clearly record the question, eligibility conditions and reasons for changes, and distinguish variations of the intervention.", "review_level": "Relevant sections of the original web text reviewed directly; not an application of the chapter's entire methodology" }, { "id": "M04", "version": "Cochrane Handbook 6.5.1 (2025), chapter updated 2025-03", "url": "https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-04", "section": "§4.5, §4.6.1–4.6.3, MECIR C42", "official_principle": "Distinguish and link studies and reports; do not omit a study solely because an outcome is unreported.", "review_level": "Relevant sections of the original web text reviewed directly; not an application of the chapter's entire methodology" }, { "id": "M08", "version": "Cochrane Handbook 6.5 (2024), chapter updated 2019-10", "url": "https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-08", "section": "§8.1–8.2.3, Table 8.2.a", "official_principle": "Define the result and effect of interest before examining randomization, deviations, missing data, measurement and selective reporting.", "review_level": "Relevant sections of the original web text reviewed directly; not an application of the chapter's entire methodology" }, { "id": "M15", "version": "Cochrane Handbook 6.5 (2024), chapter updated 2023-08", "url": "https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-15", "section": "§15.2.4, §15.3.1–15.3.3", "official_principle": "Distinguish effect estimates, intervals, importance and applicability. Sample size alone does not determine precision.", "review_level": "Relevant sections of the original web text reviewed directly; not an application of the chapter's entire methodology" }, { "id": "M19", "version": "Cochrane Handbook 6.5 (2024), chapter updated 2019-10", "url": "https://www.cochrane.org/authors/handbooks-and-manuals/handbook/current/chapter-19", "section": "§19.1.2, §19.2.1–19.2.4", "official_principle": "Harm questions may require different designs, populations and follow-up than efficacy questions. Case reports do not establish incidence rates.", "review_level": "Relevant sections of the original web text reviewed directly; not an application of the chapter's entire methodology" } ], "status_dictionary": { "Partly verified": "Some required conditions were verified in the stored summary. This does not mean all conditions were met", "Unverified": "Required information/conditions could not be established within this review's scope", "Review incomplete": "Original-material comparisons/searches within the permitted scope were not performed", "Not reported": "A scope-limited status meaning that the item was not stated in the particular material/section that was read", "Inaccessible": "Used only when access was actually attempted and failed. Not assigned to the clinical materials in this review", "Insufficient evidence for the conditions": "Used only after relevant studies within a defined scope have been reviewed and evidence answering the conditions is insufficient. Not applied across the board in this review", "Not applicable": "A specific exception based on applicability conditions. Not a replacement status for unread materials", "Conflicting data": "Used when compared data for the same question, time point and analysis are difficult to reconcile. Not assigned merely because review estimates differ", "Met": "All required conditions can be explained using locations in original sources. Not synonymous with established efficacy" }, "study_overlap": { "state": "Unverified", "unique_trial_count": null, "unique_participant_count": null, "reason": "Review inclusion tables and original-trial identities are unverified. S02's restatement and S03's update are not added together as independent populations" }, "history": [ { "date": "2026-10-07", "kind": "Separation of public-facing pages and materials", "view_version": "1.0", "change": "Public-facing pages and materials were prepared from the existing 22 items. No new clinical search, verification-status changes or scoring were performed." } ], "language": "en", "translation_date": "2026-10-09" }