Abstract
Background and Objectives
Comparing observed and expected distributions of baseline continuous variables in
randomized controlled trials (RCTs) can be used to assess publication integrity. We
explored whether baseline categorical variables could also be used.
Methods
The observed and expected (binomial) distribution of all baseline categorical variables
were compared in four sets of RCTs: two controls, and two with publication integrity
concerns. We also compared baseline calculated and reported P-values.
Results
The observed and expected distributions of baseline categorical variables were similar
in the control datasets, both for frequency counts (and percentages) and for between-group
differences in frequency counts. However, in both sets of RCTs with publication integrity
concerns, about twice as many variables as expected had between-group differences
in frequency counts of one or 2, and far fewer variables than expected had between-group
differences of >4 (P < 0.001 for both datasets). Furthermore, about one in six reported P-values for baseline categorial variables differed by > 0.1 from the calculated P-value in trials with publication integrity concerns.
Conclusion
Comparing the observed and expected distributions and reported and calculated P-values of baseline categorical variables may help in the assessment of publication
integrity of a body of RCTs.
Keywords
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Article info
Publication history
Published online: December 27, 2022
Accepted:
December 21,
2022
Footnotes
Funding: This research received no specific funding. MB is a recipient of an HRC Clinical Practitioners Fellowship. The Health Services Research Unit is funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. The authors are independent of the HRC. The HRC had no role in design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Competing interest: None of the authors have a conflict of interest to declare.
Declarations of interest: None.
Authors contributions: MB, GG, AA, DC, and AG designed the research. MB and DC provided the existing datasets and MB extracted any new data. MB and GG performed the analyses. MB drafted the paper. All authors critically reviewed and improved it. All authors read and approved the final manuscript.
Identification
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© 2022 Elsevier Inc. All rights reserved.
