Responsiveness of the foot and ankle ability measure (FAAM) in individuals with diabetes

Abstract

Background The impact of diabetes on physical function pose a challenge in assessing clinical outcomes. Objective The purpose of this study was to provide evidence of responsiveness for the foot and ankle ability measures (FAAM) in individuals with diabetes mellitus. Methods The two most recent FAAM scores of 155 diabetic patients treated for foot/ankle pathology were analyzed. Based on physical component summary (PCS) scores of the SF-36, subjects were categorized as improved (>7-point positive change), worsened (>7-point negative change), or unchanged (<7-point change). Analyses of the worsened and improved groups were compared to the unchanged group using two-way repeated measures ANOVAs and ROC curve analyses. Results The ANOVAs demonstrated a significant difference between groups ( P = 0.001). ROC curves analysis for detecting an improvement or decline in status were 0.73 (95% CI 0.62–0.84) and 0.70 (95% CI 0.59–0.81), respectively. An increase in FAAM score of 9 points represented the minimal clinically important difference (MCID) with 0.64 sensitivity and 0.78 specificity. A decrease in FAAM score of 2 points represented a MCID with 0.65 sensitivity and 0.61 specificity. Conclusions The FAAM demonstrated responsiveness to change in individuals with orthopedic foot and ankle dysfunction complicated by diabetes and can be used to measure patient outcomes over a 6-month period.