Abstract
BACKGROUND: Core outcome sets for people with multiple long-term conditions (multimorbidity) intervention studies offer an opportunity to compare data across studies and countries. However, a key research gap remains: the development of the World Health Organization (WHO) International Classification of Functioning, Disability and Health (ICF) Core Set for multimorbidity rehabilitation. ICF Core Sets are a selection of essential categories from the full ICF classification that are considered most relevant for describing the functioning of a person with a specific health condition or in a specific healthcare context. This study aims to develop and validate an ICF Core Set for exercise-based multimorbidity rehabilitation. Unlike system- or disease-specific rehabilitation, multimorbidity rehabilitation entails using a modified structure that accommodates all conditions that an individual with multimorbidity has. METHODS: The three-phase, multi-method process created by the WHO and ICF Research Branch will be followed. The process will involve conducting four preparatory studies (phase 1), including (i) a systematic literature review (to examine researcher perspectives), (ii) a qualitative study (to examine patient perspectives), (iii) an expert survey (to examine health professional perspectives), and (iv) an empirical study (to examine clinical perspectives). This will be followed by an international consensus conference (phase 2) where lists of ICF categories resulting from phase 1 studies will be consolidated into a first version of an ICF Core Set for multimorbidity rehabilitation, which will be validated using an international comparative data analysis (phase 3). CONCLUSION: An ICF Core Set created for multimorbidity rehabilitation will (1) benefit patients with multimorbidity who are often excluded from clinical trials of single-disease rehabilitation programs, (2) ensure precise and comprehensive assessment and documentation of functioning and disability relevant to this patient population, (3) help rehabilitation providers and their patients and/or caregivers when setting rehabilitation goals and planning rehabilitative interventions to achieve those goals, (4) help researchers in the synthesis of evidence for multimorbidity rehabilitation and facilitate the comparability of data across studies and countries, and (5) provide the scientific basis from which assessment tools can be derived for use in clinical and research settings and health care administration. TRIAL REGISTRATION: COMET database (https://www.comet-initiative.org/Studies/Details/3266).