SF36 physical functioning scale and 2-minute walk test advocated as core qualifiers to evaluate physical functioning in patients with late-onset sequelae of poliomyelitis

OBJECTIVE: To select a questionnaire and walking capacity test based on comparison of clinimetric properties and mutual association to be used as "core" qualifiers for physical functioning in patients with late-onset sequelae of poliomyelitis. DESIGN: Repeated-measures at 3-week intervals. SUBJECTS: An unselected sample of 57 patients with late-onset sequelae of poliomyelitis from a prospective cohort study. METHODS: Physical functioning scales from Short Form-36 (SF36-PF), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC-PF) and Nottingham Health Profile (NHP-PM). Timed-Up-and-Go test, 10-m walking at self-preferred and maximum speed, and 2-min walk test. RESULTS: Test-retest reliability of SF36-PF and WOMAC-PF was good (intraclass correlation coefficient (ICC) 0.92 and 0.89, respectively), sufficient for NHP-PM (ICC 0.74) and excellent for walking tests (ICC 0.93-0.96). The smallest detectable changes were 18.4 and 16.5, respectively, for WOMAC-PF and SF36-PF, and 26.7 for NHP-PM. The smallest detectable change was best for the 2-min walk test (22.9 m). Correlation coefficients between questionnaires and walking tests ranged from 0.32 to 0.69, with the highest correlation between the SF36-PF and 2-min walk test. CONCLUSION: The SF36-PF and 2-min walk test are recommended as core qualifiers for physical functioning, the major increasing disability in late-onset sequelae of poliomyelitis, to assess perceived physical performance and walking capacity in research and clinical practice