Background: Quantitative synthesis of interventional studies is challenging owing to variations in outcome measures (domain, measurement, metric, aggregation and timepoints) and missing outcome data. Additionally, the relevance of outcome measures to people with lived experience is often unknown. Cochrane Incontinence planned to harmonise outcomes across reviews to ensure relevancy and quality.
Objectives: To facilitate the development of a core outcome set (COS) for use in randomised controlled trials (RCTs) and systematic reviews by generating a list of outcome measures.
Methods: Following COMET methodology, this work used a mixed-methods design comprising a scoping review and semistructured interviews. Nine databases were searched for outcome measures reported in RCTs and systematic reviews published from 2017 to 2022 (search date: 11/05/2022). A date restriction was applied, limiting the synthesised articles to those published between 2018 and 2022. Eligibility was children with enuresis (all subtypes), all interventions, comparators and outcomes. Two reviewers screened 20% of the records at both screening stages, with one screening the remaining. Two reviewers piloted the data extraction form with 10 articles, with one extracting the remaining articles. Semistructured interviews took place online (April to June 2022) with a convenience sample of six participants recruited by snowballing utilising existing contacts with patient organisations and professional bodies. Interviews were audio recorded, transcribed verbatim and analysed abductively using the framework method. Findings were integrated into the COMET taxonomy within five core outcome areas (mortality, physiological and clinical, life impact, resource use, and adverse events).
Results: One hundred twenty-eight outcomes were extracted verbatim from 38 synthesised articles and charted to the taxonomy alongside 262 codes generated from the interview transcripts. Enuretic episodes were a commonly reported outcome domain identified as important by participants. However, heterogeneity exists in descriptions, timings and measurements. In contrast to patient preferences, outcome domains relating to life impact and resource use were lacking in scoping review findings, possibly due to a focus on trials.
Conclusions: Reviews of interventions for treating nocturnal enuresis could be more relevant to people with lived experiences by capturing social, role and emotional functioning. In addition, outcome measures relating to enuretic episodes should be standardised to facilitate meta-analysis. Subsequent multistakeholder stages are required to finalise the development of a COS.