Clinical assessment of fear of falling after stroke: validity, reliability and responsiveness of the Persian version of the Fall Efficacy Scale-International

BACKGROUND Fear of falling may be related to falling during stroke onset. The Fall Efficacy ScaleInternational (FES-I) with excellent psychometric properties, is an instrument developed to assess patients' concerns about fallings. The aim of this study was to determine validation of this scale in Iranian patients with stroke. METHODS The "forward-backward" procedure was applied to translate the FES-I from English to Persian. One hundred-twenty patients who had suffered stroke, aged 40 to 80 years (55% male) completed the Persian FES-I, Geriatric Depression Scale-15 (GDS-15), General Health Questionnaire-28 (GHQ-28), Berg Balance Scale (BBS) and Timed up and Go (TUG) questionnaires. The interval time for the test-retest of the Persian scale was 7-14 days. RESULTS The test-retest and inter-rater reliabilities of the Persian FES-I were excellent (ICC2,1=0.98, p<0.001) and the internal consistency was high (Cronbach's alpha=0.78). Factor analysis of the 16 items in the Persian scale showed only one significant factor. The total Persian FES-I score had a significantly negative correlation (p<0.001) with the BBS, but it had significantly positive correlation with the TUG, GHQ-28, and GDS-15. The difference in responsiveness scores across fallers and non-fallers yielded a large effect size (0.46), which indicated a good discriminating validity. CONCLUSION The Persian FES-I proved to be an effective and valuable measurement tool to assess stroke patients' fear of falling in practice and research setting.