Article

Objective: To develop a hierarchical scale that measures activity limitations in climbing stairs in patients with lower-extremity disorders living at home. Design: Cross-sectional study with Mokken scale analysis of 15 dichotomous items. Setting: Outpatient clinics of secondary and tertiary care centers. Participants: Patients (N=759; mean age standard deviation. 59.8 +/- 15.0y; 48% men) living at home, with different lower-extremity disorders: stroke, poliomyelitis, osteoarthritis, amputation, complex regional pain syndrome type 1, and diabetic foot problems. Interventions: Not applicable. Main Outcome Measures: (1) Fit of the monotone homogeneity model, indicating whether items can be used for measuring patients: (2) fit of the double monotonicity model, indicating invariant (hierarchical) item ordering; (3) intratest reliability. Indicating repeatability of the sum score; and (4) differential item functioning, addressing the validity of comparisons between subgroups of patients. Results: There was (1) good fit of the monotone homogeneity model (coefficient H=.50) for all items for all patients, and for subgroups defined by age, gender, and diagnosis; (2) good fit of the double monotonicity model (coefficient H-T=.58); (3) good intratest reliability (coefficient rho=.90); and (4) no differential item functioning with respect to age and gender. But differential item functioning for 4 items in amputees compared with nonamputees. Conclusions: A hierarchical scale, with excellent scaling characteristics. Has been developed for measuring activity limitations in climbing stairs in patients with lower-extremity disorders who live at home. However, measurements should be interpreted with caution when comparisons are made between patients with and without amputation. (C) 2004 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.

Langue : ANGLAIS