Samenvatting

Chronic conditions can lead to considerable deterioration in functioning. Several condition-specific Core Sets, selections of categories from the International Classification of Functioning, Disability and Health (ICF), have been developed to facilitate the rehabilitation process. Considering the increase in patients with more than one specific condition, we evaluated the impact of multimorbidity on functioning and the implications for the Core Set approach. Design: Internet survey. Multimorbidity seriously aggravates the already existing functioning problems of people with rheumatic disease. We recommend that in the ICF Core Set approach more emphasis is given to systematic empirical analysis of the impact of multimorbidity on functioning.