Construction and pilot assessment of the Lower Limb Function Assessment Scale.

Abstract

Stroke often leads to upright standing and walking impairments. Clinical assessments do not sufficiently address ecological aspects and the patient's subjective evaluation of function. To perform a pilot assessment of the psychometric properties of the Lower Limb-Function Assessment Scale (LL-FAS). The LL-FAS includes 30 items assessing the patient's perception (in a questionnaire) and the examiner's perception (in a practical test) of upright standing and walking impairments and their impact on activities of daily living. We analyzed the LL-FAS's reliability, construct validity, internal consistency, predictive validity and feasibility. Thirty-five stroke patients were included. The scale's mean ± SD completion time was 25 ± 6 min. Intra-observer reliability was good to excellent (intraclass correlation coefficients (ICC >0.82). Interobserver reliability was moderate (0.67 < ICC < 0.9). The questionnaire and test items showed excellent construct validity for neuromotor disabilities (p < 0.05), postural ability (Postural Assessment Scale for Stroke; p < 10-5), severity of gait disorders (Gait Assessment and Intervention Tool; p < 10-3), walking ability (New Functional Ambulation Categories, 10 m walk test, Rivermead Mobility Index; p < 10-3) and functional level (Barthel Index; p < 10-3). Internal consistency (Cronbach-α >0.9) and predictive validity were excellent. The LL-FAS showed fair psychometric properties in this pilot study and may be of value for evaluating post-stroke lower limb impairment.