Reliability and validity of the Modified Functional Ambulation Classification in patients with hip fracture

A psychometrically sound and easily applicable mobility outcome measure is crucial for evaluating patient performance and efficacy of rehabilitative treatment. The Modified Functional Ambulation Classification (MFAC) is an assessment tool designed to categorize functional ambulation ability. This study aimed to evaluate the reliability and concurrent validity of the MFAC in patients with hip fracture in a rehabilitation hospital setting. A total of 122 patients with hip fracture, aged 81.3 ± 6.5 years, were evaluated using the MFAC and Elderly Mobility Scale (EMS). Inter-rater reliability was assessed by administering the MFAC to the same patients by two independent raters. Intraclass correlation (2,1) was used to calculate inter-rater reliability, and the Spearmen correlation was used to assess the correlation between MFAC and EMS scores (i.e., concurrent validity). The results revealed that the MFAC categories provided by the two raters were highly reliable (intraclass correlation coefficient (ICC) = 0.960, 95% confidence interval: 0.942-0.972, p < 0.001). The MFAC scores were also significantly correlated with the EMS scores (ρ = 0.814, p < 0.001). In conclusion, the MFAC demonstrated good reliability and concurrent validity in patients with hip fracture.