Cross-sectional study of preprints and final journal publications from COVID-19 studies: discrepancies in results reporting and spin in interpretation

Lisa Bero; Rosa Lawrence; Louis Leslie; Kellia Chiu; Sally McDonald; Matthew J Page; Quinn Grundy; Lisa Parker; Stephanie Boughton; Jamie J Kirkham; Robin Featherstone

doi:10.1136/bmjopen-2021-051821

Cross-sectional study of preprints and final journal publications from COVID-19 studies: discrepancies in results reporting and spin in interpretation

BMJ Open. 2021 Jul 16;11(7):e051821. doi: 10.1136/bmjopen-2021-051821.

Authors

Affiliations

¹ General Internal Medicine/Public Health/Center for Bioethics and Humanities, University of Colorado-Anschutz Medical Campus, Denver, Colorado, USA LISA.BERO@CUANSCHUTZ.EDU.
² Center for Bioethics and Humanities, University of Colorado - Anschutz Medical Center, Denver, Colorado, USA.
³ Charles Perkins Centre and School of Pharmacy, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.
⁴ School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
⁵ Faculty of Nursing, University of Sydney, Toronto, Ontario, Canada.
⁶ Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia.
⁷ Editorial and Methods Department, Cochrane, London, UK.
⁸ Biostatistics, Manchester University, Manchester, UK.

Abstract

Objective: To compare results reporting and the presence of spin in COVID-19 study preprints with their finalised journal publications.

Design: Cross-sectional study.

Setting: International medical literature.

Participants: Preprints and final journal publications of 67 interventional and observational studies of COVID-19 treatment or prevention from the Cochrane COVID-19 Study Register published between 1 March 2020 and 30 October 2020.

Main outcome measures: Study characteristics and discrepancies in (1) results reporting (number of outcomes, outcome descriptor, measure, metric, assessment time point, data reported, reported statistical significance of result, type of statistical analysis, subgroup analyses (if any), whether outcome was identified as primary or secondary) and (2) spin (reporting practices that distort the interpretation of results so they are viewed more favourably).

Results: Of 67 included studies, 23 (34%) had no discrepancies in results reporting between preprints and journal publications. Fifteen (22%) studies had at least one outcome that was included in the journal publication, but not the preprint; eight (12%) had at least one outcome that was reported in the preprint only. For outcomes that were reported in both preprints and journals, common discrepancies were differences in numerical values and statistical significance, additional statistical tests and subgroup analyses and longer follow-up times for outcome assessment in journal publications.At least one instance of spin occurred in both preprints and journals in 23/67 (34%) studies, the preprint only in 5 (7%), and the journal publications only in 2 (3%). Spin was removed between the preprint and journal publication in 5/67 (7%) studies; but added in 1/67 (1%) study.

Conclusions: The COVID-19 preprints and their subsequent journal publications were largely similar in reporting of study characteristics, outcomes and spin. All COVID-19 studies published as preprints and journal publications should be critically evaluated for discrepancies and spin.

Keywords: ethics (see Medical Ethics); public health; qualitative research.

MeSH terms

COVID-19 Drug Treatment*
Coronavirus Infections*
Cross-Sectional Studies
Humans
SARS-CoV-2