The value of core outcome sets in health psychology

Selective outcome reporting in trials of behavioural health interventions in health psychology and behavioural medicine journals: a review

Selective outcome reporting can result in overestimation of treatment effects, research waste, and reduced openness and transparency. This review aimed to examine selective outcome reporting in trials of behavioural health interventions and determine potential outcome reporting bias. A review of nine health psychology and behavioural medicine journals was conducted to identify randomised controlled trials of behavioural health interventions published since 2019. Discrepancies in outcome reporting were observed in 90% of the 29 trials with corresponding registrations/protocols. Discrepancies included 72% of trials omitting prespecified outcomes; 55% of trials introduced new outcomes. Thirty-eight percent of trials omitted prespecified and introduced new outcomes. Three trials (10%) downgraded primary outcomes in registrations/protocols to secondary outcomes in final reports; downgraded outcomes were not statistically significant in two trials. Five trials (17%) upgraded secondary outcomes to primary outcomes; upgraded outcomes were statistically significant in all trials. In final reports, three trials (7%) omitted outcomes from the methods section; three trials (7%) introduced new outcomes in results that were not in the methods. These findings indicate that selective outcome reporting is a problem in behavioural health intervention trials. Journal- and trialist-level approaches are needed to minimise selective outcome reporting in health psychology and behavioural medicine.

A survey of knowledge, perceptions and use of core outcome sets among clinical trialists

Background

Core outcome sets (COS) are standardised sets of outcomes, which represent the minimum outcomes that should be measured and reported in clinical trials. COS can enhance comparability across health trials by reducing heterogeneity of outcome measurement and reporting and potentially minimising selective outcome reporting. Examining what researchers involved in trials know and think about COS is essential to increase awareness and promote COS uptake. The aim of this study is therefore to examine clinical trialists’ knowledge, perceptions and experiences of COS.

Methods

An online survey design was used. Participants were clinical trialists, operationalised for the current study as researchers named as the contact person on a trial registered on the International Standard Randomised Controlled Trial Number (ISRCTN) Trial repository between 1 January 2019 and 21 July 2020. Survey items assessed clinical trialists’ familiarity with and understanding of COS, along with experiences of COS use and development.

Results

Of 1913 clinical trialists contacted to participate, 62 (3%) completed the survey. Forty (65%) participants were familiar with COS and, of those familiar with COS, 21 (55%) had been involved in a trial that used a COS. Of clinical trialists who used COS in a trial(s), less than half (n = 9, 41%) reported that all COS outcomes were used. The main barriers to using COS are poor knowledge about COS (n = 43, 69%) and difficulties identifying relevant COS (n = 42, 68%). Clinical trialists also reported perceptions of COS as restrictive and often containing too many outcomes. The main enablers to using COS are clear understanding (n = 51, 82%) and perceived importance of COS (n = 44, 71%).

Conclusions

Enhancing clinical trialists’ use of all COS outcomes is needed to reduce outcome heterogeneity and enhance comparability across trial findings. Enhancing awareness of COS importance among researchers and funders is needed to ensure that COS are developed and used by clinical trialists. Education and training may further promote awareness and understanding of COS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05891-5.

Use of core outcome sets was low in clinical trials published in major medical journals

OBJECTIVES

To examine current practices in late-phase trials published in major medical journals and examine trialists' views about core outcome set (COS) use.

STUDY DESIGN AND SETTING

A sequential multi-methods study was conducted. We examined late-phase trials published between October 2019 and March 2020 in JAMA, NEJM, The Lancet, BMJ, and Annals of Internal Medicine. The COMET database was searched for COS potentially relevant to trials not reporting using a COS; overlap of trial and COS outcomes was examined. An online survey examined awareness of, and decisions to search for and use a COS.

RESULTS

Ninety-five trials were examined; 93 (98%) did not report using a COS. Relevant COS were identified for 31 trials (33%). Core outcomes were measured in 9 (23%) studies; all trials measured at least one core outcome. Thirty-one trialists (33%) completed our survey. The most common barrier to COS use was trialist's own outcome preferences and choice (68%). The most common perceived facilitator was awareness and knowledge about COS (90%).

CONCLUSION

COS use in this cohort of trials was low, even when relevant COS were available. Increased use of COS in clinical trials can improve evaluation of intervention effects and evidence synthesis and reduce research waste.