Test-retest Reliability, Convergent Validity, and Internal Consistency of the Persian Version of Fullerton Advanced Balance Scale in Iranian Community-dwelling Older Adults

Objective This study was performed to evaluate convergent validity, test-retest reliability and internal consistency of the Persian translation of the Fullerton advanced balance (FAB) for use in Iranian community-dwelling older adults and improve the quality of their functional balance assessment. Methods & Materials The original scale was translated with forward-backward protocol. In the next step, using convenience sampling and inclusion criteria, 88 functionally independent older adults were selected to participate in the study. Their mean (SD) age was 67.15(5.79) years. The Persian version of the scale was administered to each participant twice with an interval of 2-4 days by the same examiner (occupational therapist). Convergent validity was assessed by correlating the scale with Berg balance scale, timed up and go test, and functional reach test. Results The test-retest reliability of individual items indicated good to excellent reliability (Cohen's Kappa=0.63-1). Intraclass correlation coefficient was excellent (ICC=0.98), standard error of measurement was good (SEM=0.17), and minimal detectable change was 0.46. Construct validity showed moderate to good correlation between the Persian version of FAB and Berg balance scale (r=0.65), functional reach (r=0.62), and timed up and go test (r=-0.77). Internal consistency was acceptable (Cronbach alpha = 0.830.84) for both phases. Conclusion The Persian version of the FAB Scale is an acceptable and excellent psychometric instrument in assessing the multiple dimensions of balance in Iranian community-dwelling older adults.