Findings of a retrospective, controlled cohort study of the impact of a change in Nature journals' editorial policy for life sciences research on the completeness of reporting study design and execution

Abstract

ObjectiveTo determine whether a change in editorial policy, including the implementation of a checklist, has been associated with improved reporting of measures which might reduce the risk of bias.\n\nMethodsThe study protocol has been published at DOI: 10.1007/s11192-016-1964-8.\n\nDesignObservational cohort study.\n\nPopulationArticles describing research in the life sciences published in Nature journals, submitted after May 1st 2013.\n\nInterventionMandatory completion of a checklist at the point of manuscript revision.\n\nComparators(1) Articles describing research in the life sciences published in Nature journals, submitted before May 2013; (2) Similar articles in other journals matched for date and topic.\n\nPrimary OutcomeChange in proportion of Nature publications describing in vivo research published before and after May 2013 reporting the Landis 4 items (randomisation, blinding, sample size calculation, exclusions).\n\nWe included 448 NPG papers (223 published before May 2013, 225 after) identified by an individual hired by NPG for this specific task, working to a standard procedure; and an independent investigator used Pubmed Related Citations to identify 448 non-NPG papers with a similar topic and date of publication in other journals; and then redacted all publications for time sensitive information and journal name. Redacted manuscripts were assessed by 2 trained reviewers against a 74 item checklist, with discrepancies resolved by a third.\n\nResults394 NPG and 353 matching non-NPG publications described in vivo research. The number of NPG publications meeting all relevant Landis 4 criteria increased from 0/203 prior to May 2013 to 31/181 (16.4%) after (2-sample test for equality of proportions without continuity correction, X2 = 36.2, df = 1, p = 1.8 x 10-9). There was no change in the proportion of non- NPG publications meeting all relevant Landis 4 criteria (1/164 before, 1/189 after). There were more substantial improvements in the individual prevalences of reporting of randomisation, blinding, exclusions and sample size calculations for in vivo experiments, and less substantial improvements for in vitro experiments.\n\nConclusionsThere was a substantial improvement in the reporting of risks of bias in in vivo research in NPG journals following a change in editorial policy, to a level that to our knowledge has not been previously observed. However, there remain opportunities for further improvement.