Inadvertent P-hacking among trials and systematic reviews of the effect of progestogens in pregnancy? A systematic review and meta-analysis

Ref ID 201
First Author M. Prior
Journal BJOG: AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY
Year Of Publishing 2017
URL https://obgyn.onlinelibrary.wiley.com/doi/pdfdirect/10.1111/1471-0528.14506?download=true
Keywords Pre-specification
Subgroup
Endocrinology
Problem(s) Multiplicity of outcomes and lack of pre-specification for outcome reporting
Number of systematic reviews included 29
Summary of Findings Nineteen of the included 29 meta-analyses concluded that progestogens were effective which the authors suggest was due to inadvertant p-hacking. When systematic reviews evaluated only the primary outcomes from pre-registered double-blind trials with analysis, progestogen agents in pregnancy were found to be ineffective (RR 1.00 (95% CI 0.94–1.07).
Did the article find that the problem(s) led to qualitative changes in interpretation of the results? Yes
Are the methods of the article described in enough detail to replicate the study? Yes