Background context: A variety of self-report and physical performance-based outcome measures are commonly used to assess progress and recovery in the lower leg, ankle, and foot. A requisite attribute of any outcome measure is its ability to detect change in a condition, a construct known as "responsiveness". There is a lack of consistency in how responsiveness is defined in all outcome measures.
Purpose: The purpose of this study was to review the currently used recovery outcome measures for lower leg, ankle and foot conditions in order to determine and report recommended responsiveness values.
Methods: A systematic literature search that included electronic searches of PubMed, CINAHL and SportDiscus as well extensive cross-referencing was performed in January, 2013. Studies were included if each involved: 1) a prospective, longitudinal study of any design; 2) any condition associated with the lower leg, ankle or foot; 3) a measure of responsiveness; and 4) was an acceptable type of outcome measure (eg. self-report, physical performance, or clinician report). The quality of the included articles was assessed by two independent authors using the responsiveness sub-component of the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN).
Results: Sixteen different studies met the inclusion criteria for this systematic review. The most commonly used outcome measures were the Foot and Ankle Ability Measure and the Lower Extremity Functional Scale. Responsiveness was calculated in a variety of methods including effect size, standardized response mean, minimal clinically important difference/importance, minimal detectable change, and minimal important change.
Conclusion: Based on the findings of this systematic review there is a lack of consistency for reporting responsiveness among recovery measures used in the lower leg, ankle or foot studies. It is possible that the variability of conditions that involve the lower leg, ankle and foot contribute to the discrepancies found in reporting responsiveness values. Further research must be conducted in order to standardize reporting measures for responsiveness.
Level of evidence: 2a.
Keywords: Ankle; outcome measures; responsiveness.