Development of a core outcome set for use in community-based bipolar trials—A qualitative study and modified Delphi

BACKGROUND: A core outcome set (COS) is a standardised collection of outcomes to be collected and reported in all trials within a research area. A COS can reduce reporting bias and facilitate evidence synthesis. This is currently unavailable for use in community-based bipolar trials. This research aimed to develop such a COS, with input from a full range of stakeholders. METHODS: A co-production approach was used throughout. A longlist of outcomes was derived from focus groups with people with a bipolar diagnosis and carers, interviews with healthcare professionals and a rapid review of outcomes listed in bipolar trials on the Cochrane database. An expert panel with personal and/or professional experience of bipolar participated in a modified Delphi process and the COS was finalised at a consensus meeting. RESULTS: Fifty participants rated the importance of each outcome. Sixty-six outcomes were included in Round 1 of the questionnaire; 13 outcomes were added by Round 1 participants and were rated in Round 2. Seventy-six percent of participants (n = 38) returned to Round 2 and 60 outcomes, including 4 outcomes added by participants in Round 1, received a rating of 7–9 by >70% and 1–3 by <25% of the sample. Fourteen participants finalised a COS containing 11 outcomes at the consensus meeting: personal recovery; connectedness; clinical recovery of bipolar symptoms; mental health and wellbeing; physical health; self-monitoring and management; medication effects; quality of life; service outcomes; experience of care; and use of coercion. CONCLUSIONS: This COS is recommended for use in community-based bipolar trials to ensure stakeholder-relevant outcomes, facilitate data synthesis, and transparent reporting. The COS includes guidance notes for each outcome to allow the identification of suitable measurement instruments. Further validation is recommended for use with a wide range of communities and to achieve standardised measurement.