Development and psychometric properties of the ambulatory self-confidence questionnaire.

BACKGROUND: Ambulation is one of the most important elements of mobility, and difficulty with ambulation is often cited as a common problem among older adults. Self-report assessments (e.g. walking confidence) provide complementary information to performance tests (e.g. the Timed Up and Go Test, TUG) because they offer data not obtainable from a test of walking performance.

OBJECTIVE: To develop and assess the reliability and the content and construct validity of the Ambulatory Self-Confidence Questionnaire (ASCQ), a new measure of walking confidence.

METHODS: This descriptive methodological study used data from two samples. The first sample included 31 individuals (13 community-dwelling older adults, aged 65 years and older and 18 academics, clinicians, and researchers working in the area of ambulatory care and geriatrics and medicine) who assisted in establishing the content validity. Participants were asked to complete two surveys to assess the content of the ASCQ. For the second sample 101 community-dwelling older adults (>/=65 years old) were recruited, from community centers, senior day centers, and geriatric clinics in order to determine the reliability and construct validity of the ASCQ. The ASCQ was completed twice over a 2-week interval while other measures such as the TUG, the 6-Min Walk Test (6MWT), the Activities-specific Balance Confidence scale (ABC) and the Instrumental Activities of Daily Living scale (IADL) were completed once in order to assess validity.

RESULTS: Group consensus was obtained for a 22-item version of the ASCQ. Of the 101 participants recruited for the project, 67 provided complete information for test-retest reliability and 91 provided information for assessment of validity. Internal consistency (Cronbach's alpha = 0.95) and test-retest reliability (ICC(1.1) = 0.92; 95% confidence interval (CI) 0.87, 0.95) were excellent. The ASCQ was: (1) highly correlated with the ABC scale (rho = 0.87); moderately correlated with the TUG (rho = -0.46) and the 6MWT (rho = 0.36); and weakly correlated with the IADL (rho = 0.27).

CONCLUSION: The ASCQ is reliable and support for validity is evident for this sample of community-dwelling older adults. Further studies are needed to assess the reliability and validity in a frailer older adult sample. The ASCQ may be useful to clinicians and researchers alike for determining an older adult's confidence with their walking ability.