Study Preregistration: Measuring What Matters: Development and Dissemination of a Core Outcome Set for Pediatric Anxiety Disorders Clinical Trials.

Pediatric anxiety disorders (AD) are prevalent disorders with an impact on all aspects of a child's life and functioning.1 Although evidence supports commonly used treatments, there are notable concerns with the research to date.2 Heterogeneity in outcome selection, measurement, analysis, and reporting is a contributing factor to the hinderance of the translation of research into clinical practice.3 Recognition for outcome standardization in pediatric mental health disorders is evolving and there are several initiatives of importance, including the International Consortium for Health Outcomes Measurement (ICHOM), which has developed standardized outcome sets for use in the routine clinical mental health treatment of children and adolescents.4 Similarly, the International Alliance of Mental Health Research Funders5 advocate for use of 1 specific outcome measurement instrument (OMI) in the youth mental health research that they fund. Development of a Core Outcome Set (COS), a minimal set of outcomes that should be measured and reported in clinical trials, has been a solution in other areas of medicine to address heterogeneity in outcome selection and measurement across trials.6 The Core Outcomes and Measures in Pediatric Anxiety Clinical Trials (COMPACT) Initiative will develop a harmonized, evidence- and consensus-based COS that is meaningful to youth and families for use in future trials in pediatric AD.

Outcomes and outcome measurement instruments reported in randomised controlled trials of anxiety disorder treatments in children and adolescents: a scoping review protocol.

INTRODUCTION: Paediatric anxiety disorders (AD) are prevalent and persistent mental health conditions worldwide affecting between 10% and 20% of children and adolescents. Despite the high prevalence of paediatric AD, there is limited understanding of which treatments work best. Outcome heterogeneity across paediatric mental health trials has been a significant factor in hindering the ability to compare results and assess the efficacy of such trials. This scoping review will help to identify and synthesise the outcomes reported in paediatric AD trials to date. METHODS AND ANALYSIS: Following the Joanna Briggs Institute scoping review methodology, a comprehensive electronic bibliographic database search (MEDLINE, APA PsycINFO, Embase, CINAHL) strategy will be applied to identify articles examining interventions for children diagnosed with an AD. Articles will be eligible for inclusion if they assess at least one AD intervention (eg, psychological), in children 4-18 years of age inclusive. Initial title and abstract screening will be completed by two trained reviewers independently and in duplicate. Full-text screening of each included article will be completed independently and in duplicate by two of three trained reviewers. Identified outcomes will be mapped to a standard outcome taxonomy developed for core outcome sets. Trial and outcome characteristics will be synthesised using quantitative metrics (counts and frequencies). ETHICS AND DISSEMINATION: As this is a scoping review of the literature and patient information or records were not accessed, institutional ethics approval was not required. Results of this scoping review will be disseminated to clinicians, researchers inclusive of trialists and other stakeholders invested in outcome selection, measurement and reporting in paediatric AD trials. In addition, scoping review results will inform the development of a Core Outcome Set for paediatric AD trials-a minimum set of outcomes that should be measured across trials in an area of health, without precluding the inclusion of other outcomes.