Towards a standardised brief outcome measure: Psychometric properties and utility of the CORE–OM

Abstract

BackgroundAn acceptable, standardised outcome measure to assess efficacy and effectiveness is needed across multiple disciplines offering psychological therapies.AimsTo present psychometric data on reliability, validity and sensitivity to change for the CORE–OM (Clinical Outcomes in Routine Evaluation – Outcome Measure).MethodA 34-item self-report instrument was developed, with domains of subjective well-being, symptoms, function and risk. Analysis includes internal reliability, test–retest reliability, socio-demographic differences, exploratory principal-component analysis, correlations with other instruments, differences between clinical and non-clinical samples and assessment of change within a clinical group.ResultsInternal and test–retest reliability were good (0.75–0.95), as was convergent validity with seven other instruments, with large differences between clinical and non-clinical samples and good sensitivity to change.ConclusionsThe CORE–OM is a reliable and valid instrument with good sensitivity to change. It is acceptable in a wide range of practice settings.