Evidence map›Paper›PMID 36949524›Full record

ArticleTrials2023

A retrospective analysis of conditional power assumptions in clinical trials with continuous or binary endpoints.

Julia M Edwards, Stephen J Walters, Steven A Julious

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Article in Trials, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 4 papers.

0numbers the graph read from it
0cells of the map it votes in
4citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

4 citing papers in PubMed.

  1. Article
  2. Futility Interim Analyses - A Plea for Simplicity.Therapeutic innovation & regulatory science · 2025
    Article
  3. Article
  4. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Julia M EdwardsSchool of Health and Related Research, The University of Sheffield, 30 Regent Street, Sheffield, S1 4DA, UK. julia.edwards@icnarc.org.ORCID http://orcid.org/0000-0001-8337-8962
Stephen J WaltersSchool of Health and Related Research, The University of Sheffield, 30 Regent Street, Sheffield, S1 4DA, UK.
Steven A JuliousSchool of Health and Related Research, The University of Sheffield, 30 Regent Street, Sheffield, S1 4DA, UK.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundAdaptive clinical trials may use conditional power (CP) to make decisions at interim analyses, requiring assumptions about the treatment effect for remaining patients. It is critical that these assumptions are understood by those using CP in decision-making, as well as timings of these decisions.

methodsData for 21 outcomes from 14 published clinical trials were made available for re-analysis. CP curves for accruing outcome information were calculated using and compared with a pre-specified objective criteria for original and transformed versions of the trial data using four future treatment effect assumptions: (i) observed current trend, (ii) hypothesised effect, (iii) 80% optimistic confidence limit, (iv) 90% optimistic confidence limit.

resultsThe hypothesised effect assumption met objective criteria when the true effect was close to that planned, but not when smaller than planned. The opposite was seen using the current trend assumption. Optimistic confidence limit assumptions appeared to offer a compromise between the two, performing well against objective criteria when the end observed effect was as planned or smaller.

conclusionThe current trend assumption could be the preferable assumption when there is a wish to stop early for futility. Interim analyses could be undertaken as early as 30% of patients have data available. Optimistic confidence limit assumptions should be considered when using CP to make trial decisions, although later interim timings should be considered where logistically feasible.

Indexed as

Medical FutilityResearch DesignAdaptive Clinical Trials as TopicHumansRetrospective StudiesSample SizeAdaptive designsClinical trialsConditional powerFutilitySample size re-estimation

Identifiers

PMID36949524
PMCPMC10035140

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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.