Reliability and validity of the Persian version of Foot and Ankle Ability Measure (FAAM) to measure functional limitations in patients with foot and ankle disorders

Abstract

Objective: To translate the Foot and Ankle Ability Measure (FAAM) into Persian and to evaluate the psychometric properties of the Persian version of FAAM. Methods: 93 patients with a range of foot and ankle disorders, completed the Persian version of the FAAM and Short-Form 36 Health Survey (SF-36) in the test session. With an interval of 2-6 days, 60 patients filled out the FAAM in the retest session. The FAAM is composed of two subscales including activities of daily living (ADL) and SPORTS. Internal consistency was assessed using Cronbach's alpha, test-retest reliability using intraclass correlation coefficient (ICC) and standard error of measurement (s.e.m.), item internal consistency and discriminant validity using Spearman's correlation coefficient and construct validity using Spearman's correlation coefficient and Independent t-test. Results: Cronbach's alpha coefficient of 0.97 and 0.94 was obtained for ADL and SPORTS subscales, respectively. The ICC and s.e.m. were 0.98 and 3.13 for ADL and 0.98 and 3.53 for SPORTS subscale. Items were stronger measures of their hypothesized subscale than of other subscale. The ADL and SPORTS subscales had stronger correlation with SF-36 physical function (r=0.60, 0.53) and physical health summary measure (r=0.61, 0.48) than with SF-36 mental health (r=0.21, 0.10) and mental health summary measure (r=0.36, 0.27). A high correlation was found between FAAM scores and global scale of functional status for SPORTS (r=0.73) but not for ADL (r=0.42). FAAM scores were greater in individuals who rated their function as normal or nearly normal compared with those who rated as abnormal or severely abnormal for SPORTS (P=0.04) but not for ADL (P=0.15). Conclusion: The Persian version of FAAM is a reliable and valid measure to quantify physical functioning in patients with foot and ankle disorders. © 2010 Osteoarthritis Research Society International.