Are the ICF activity and participation dimensions distinct?

Objective: To test the hypothesis that distinct Activity and Participation dimensions of the International Classification of Functioning, Disability, and Health could be identified using physical functioning items drawn from the Late Life Function and Disability Instrument. Design: A cross-sectional, survey design was employed. Subjects: The sample comprised 150 community-dwelling adults aged 60 years and older. Methods: Exploratory factor analysis was used to identify interpretable dimensions underlying 48 physical functioning questionnaire items. Results: Findings revealed that one conceptual dimension underlying these physical functioning items was not sufficient to adequately explain the data (X-2=2383; p<0.0001). A subsequent solution produced 3 distinct, interpretable factors that accounted for 61.1% of the variance; they were labeled: Mobility Activities (24.4%), Daily Activities (24.3%), and Social/Participation (12.4%). All 3 factors achieved high internal consistency with coefficient alphas of 0.90 or above. Conclusion: Within physical functioning, distinct concepts were identified that conformed to the dimensions of Activity and Participation as proposed in the ICF. We believe this is the first empirical evidence of separate Activity and Participation dimensions within the International Classification of Functioning, Disability, and Health classification.