A third of systematic reviews changed or did not specify the primary outcome: A PROSPERO register study

TY - JOUR

T1 - A third of systematic reviews changed or did not specify the primary outcome

T2 - A PROSPERO register study

AU - Tricco, Andrea C

AU - Cogo, Elise

AU - Page, Matthew J

AU - Polisena, Julie

AU - Booth, Alison

AU - Dwan, Kerry

AU - MacDonald, Heather

AU - Clifford, Tammy J

AU - Stewart, Lesley A

AU - Straus, Sharon E

AU - Moher, David

N1 - Copyright © 2016 Elsevier Inc. All rights reserved.

PY - 2016/4/11

Y1 - 2016/4/11

N2 - OBJECTIVES: To examine outcome reporting bias of systematic reviews registered in PROSPERO.STUDY DESIGN AND SETTING: Retrospective cohort study. The primary outcomes from systematic review publications were compared with those reported in the corresponding PROSPERO records; discrepancies in the primary outcomes were assessed as upgrades, additions, omissions or downgrades. Relative risks (RR) and 95% confidence intervals (CI) were calculated to determine the likelihood of having a change in primary outcome when the meta-analysis result was favourable and statistically significant.RESULTS: 96 systematic reviews were published. A discrepancy in the primary outcome occurred in 32% of the included reviews and 39% of the reviews did not explicitly specify a primary outcome(s); 6% of the primary outcomes were omitted. There was no significant increased risk of adding/upgrading (RR 2.14, 95% CI 0.53 to 8.63) or decreased risk of downgrading (RR 0.76, 0.27-2.17) an outcome when the meta-analysis result was favourable and statistically significant. As well, there was no significant increased risk of adding/upgrading (RR 0.89, 0.31-2.53) or decreased risk of downgrading (RR 0.56, 0.29-1.08) an outcome when the conclusion was positive.CONCLUSIONS: We recommend review authors carefully consider primary outcome selection and journals are encouraged to focus acceptance on registered systematic reviews.

AB - OBJECTIVES: To examine outcome reporting bias of systematic reviews registered in PROSPERO.STUDY DESIGN AND SETTING: Retrospective cohort study. The primary outcomes from systematic review publications were compared with those reported in the corresponding PROSPERO records; discrepancies in the primary outcomes were assessed as upgrades, additions, omissions or downgrades. Relative risks (RR) and 95% confidence intervals (CI) were calculated to determine the likelihood of having a change in primary outcome when the meta-analysis result was favourable and statistically significant.RESULTS: 96 systematic reviews were published. A discrepancy in the primary outcome occurred in 32% of the included reviews and 39% of the reviews did not explicitly specify a primary outcome(s); 6% of the primary outcomes were omitted. There was no significant increased risk of adding/upgrading (RR 2.14, 95% CI 0.53 to 8.63) or decreased risk of downgrading (RR 0.76, 0.27-2.17) an outcome when the meta-analysis result was favourable and statistically significant. As well, there was no significant increased risk of adding/upgrading (RR 0.89, 0.31-2.53) or decreased risk of downgrading (RR 0.56, 0.29-1.08) an outcome when the conclusion was positive.CONCLUSIONS: We recommend review authors carefully consider primary outcome selection and journals are encouraged to focus acceptance on registered systematic reviews.

U2 - 10.1016/j.jclinepi.2016.03.025

DO - 10.1016/j.jclinepi.2016.03.025

M3 - Article

C2 - 27079845

SN - 0895-4356

VL - 79

SP - 46

EP - 54

JO - Journal of Clinical Epidemiology

JF - Journal of Clinical Epidemiology

ER -