ReviewTrials2025
Multiplicity adjustment approaches in publicly funded multi-arm trials: a comprehensive review of the National Institute for Health and Care Research (NIHR) Journals Library.
Review in Trials, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
1 citing paper in PubMed.
- A Cautionary Note on Regional Consistency Evaluation With Multiple Primary Endpoints in Multiregional Clinical Trials.Pharmaceutical statisticsArticle
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundParallel-group multi-arm trials are randomised controlled trials (RCTs) where participants are allocated to three or more concurrent treatment groups. Multiplicity occurs when several statistical tests are conducted within the same study. Statistical adjustments to the design and analysis of multi-arm trials can be used to control the study-wise type I error rate. There is no clear guidance or consensus on the necessity of multiplicity adjustment in multi-arm trials, nor on which methods are most appropriate. This comprehensive review aimed to investigate the design, analysis and reporting of publicly funded parallel-group multi-arm trials and to report the approach to multiplicity in these trials with respect to sample size and statistical analysis.
methodsWe searched the United Kingdom's National Institute for Health and Care Research (NIHR) online Journals Library, from 1 January 1997 to 31 December 2024 for reports of multi-arm RCTs. Information on the trial characteristics, the sample size estimation and analysis of the primary outcome was extracted. Two researchers conducted the search and selected reports for inclusion. Data from each report was independently extracted by two reviewers, and any disagreement was resolved by discussion.
resultsA total of 2452 reports, published online in the NIHR Journals Library, were screened for eligibility; 97 reports of multi-arm parallel-group trials met the inclusion criteria. Of these, 90 included the results of a multi-arm efficacy analysis. In the review, 35% (34/97) of the trials did adjust for multiplicity in the sample size calculation; in 84% (76/90), the potential between-arm comparisons were described in the methods, and 37% (33/90) made a multiplicity adjustment in the analysis. A further 86% (77/86) reported 95% confidence intervals. For the minority of multi-arm trials that did adjust for multiplicity, the most common adjustment method was Bonferroni.
conclusionsThe majority of the publicly funded multi-arm trials did not adjust for multiplicity in the sample size, statistical analysis, or estimation of confidence intervals. Researchers should follow the Consolidated Standards of Reporting Trials guidelines for multi-arm trials and clearly state in protocols and trial reports whether a multiplicity adjustment was made or provide a reason if no adjustment was made.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.