8 research outputs found
Measuring activity limitations in walking: development of a hierarchical scale for patients with lower-extremity disorders who live at home
Objective: To develop a hierarchical scale that measures activity limitations in walking in patients with lower-extremity disorders who live at home. Design: Cross-sectional study. Setting: Orthopedic workshops and outpatient clinics of secondary and tertiary care centers. Participants: Patients (N=981; mean age ± standard deviation, 58.6±15.4y; 46% men) living at home, with different lower-extremity disorders: stroke, poliomyelitis, osteoarthritis, amputation, complex regional pain syndrome type I, and diabetic and degenerative foot disorders. 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; (4) robustness, addressing the clinimetric properties within subgroups of patients; and (5) differential item functioning, addressing the validity of comparisons between subgroups of patients. Results: Thirty-five of 41 dichotomous items had (1) good fit of the monotone homogeneity model (coefficient H=.50), (2) good fit of the double monotonicity model (coefficient