Randomized trials addressing a similar question are commonly published after a trial stopped early for benefit

J Clin Epidemiol. 2017 Feb:82:12-19. doi: 10.1016/j.jclinepi.2016.10.006. Epub 2016 Nov 8.

Abstract

Objective: We explored how investigators of ongoing or planned trials respond to the publication of a trial stopped early for benefit addressing a similar question.

Study design and setting: We searched multiple databases from the date of publication of the truncated trial through August, 2015. Independent reviewers selected trials and extracted data.

Results: We identified 207 trials truncated for early benefit; of which 102 (49%) were followed by subsequent trials (262 subsequent trials, median 2 per truncated trial, range 1-13). Only 99 (38%) provided a rationale justifying conducting a trial despite prior stopping. The top reasons were to address different population or setting (33%), skepticism of truncated trials findings because of small sample size (12%), inconsistency with other evidence (11%), or increased risk of bias (7%). We did not identify significant associations between subsequent trials and characteristics of truncated ones (risk of bias, precision, funding, or rigor of stopping decision).

Conclusion: About half of the trials stopped early for benefit were followed by subsequent trials addressing a similar question. This suggests that future trialists may have been skeptic about the decision to stop prior trials. A more rigorous threshold for stopping early for benefit is needed.

Keywords: Early termination of trials; Methodology; Randomized controlled trials; Systematic review; Trial design; Trials stopped early for benefit.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Databases, Factual / statistics & numerical data
  • Early Termination of Clinical Trials*
  • Epidemiologic Studies*
  • Humans
  • Publishing / statistics & numerical data*
  • Randomized Controlled Trials as Topic / statistics & numerical data*