The Lower Extremity Functional Scale (LEFS): scale development, measurement properties, and clinical application. North American Orthopaedic Rehabilitation Research Network.

The LEFS is reliable, and construct validity was supported by comparison with the SF-36. The sensitivity to change of the LEFS was superior to that of the SF-36 in this population. The LEFS is efficient to administer and score and is applicable for research purposes and clinical decision making for individual patients.