Date of Award

January 2023

Document Type

Open Access Thesis

Degree Name

Medical Doctor (MD)

Department

Medicine

First Advisor

Joseph S. Ross

Second Advisor

Joshua D. Wallach

Abstract

The aim of this project was to evaluate the concordance among study characteristics, results, and interpretations described in preprints of clinical studies that are subsequently published in peer-reviewed journals (preprint-journal article pairs).

In this cross-sectional analysis, preprints posted on medRxiv in September 2020 were identified. Four evaluators determined how many preprints were subsequently published in peer-reviewed journals as of September 2022, calculating the time from preprint posting to publication. For preprints with multiple versions, the most recent version prior to journal acceptance was selected. Preprints updated after journal acceptance were excluded. For preprint-journal article pairs describing clinical trials, observational studies, and meta-analyses that measured health-related outcomes, sample size, primary endpoints, corresponding results, and overarching conclusions were abstracted. Results from primary endpoints were only considered concordant if they contained the same information or had numerical equivalence (e.g., identical effect size estimates and 95% CIs/P-values from inferential analyses). Rates of concordance were compared between preprints and corresponding journal articles, overall and by focus on COVID-19 and journal impact factor (IF).

Among 1399 preprints first posted on medRxiv in September 2020, a total of 1077 (77.0%) had been published as of September 15, 2022, a median of 6 months (IQR, 3-8 months) after preprint posting. Among the 547 preprint-journal article pairs describing clinical trials, observational studies, or meta-analyses, 293 (53.6%) were related to COVID-19. Of the 535 pairs reporting sample sizes in both sources, 462 (86.4%) were concordant; 43 (58.9%) of the 73 pairs with discordant sample sizes had larger samples in the journal publication. There were 534 pairs (97.6%) with concordant and 13 pairs (2.4%) with discordant primary end points. Among the 535 pairs with numerical results for the primary end points, 434 (81.1%) had concordant primary end point results; 66 of the 101 discordant pairs (65.3%) had effect size estimates that were in the same direction and were statistically consistent. Overall, 526 pairs (96.2%) had concordant study interpretations, including 82 of the 101 pairs (81.2%) with discordant primary end point results.

Most clinical studies posted as preprints on medRxiv and subsequently published in peer-reviewed journals had concordant study characteristics, results, and final interpretations. With over three-quarters of preprints published in journals within 24 months, these results may suggest that many preprints report findings that are consistent with the final peer-reviewed publications.

Comments

This is an Open Access Thesis.

Download
Open Access

This Article is Open Access

Share

COinS