Responsiveness of the Movement Ability Measure: A Self-Report Instrument Proposed for Assessing the Effectiveness of Physical Therapy Intervention

Abstract

Designed as a self-report assessment, the Movement Ability Measure (MAM) may contribute to effectiveness research if it proves responsive to change. The purpose of this article is to report evidence of responsiveness of the MAM. Thirty-five adults starting outpatient physical therapy intervention completed the MAM at the initial visit, at 2 weeks, and at 2 months or discharge. Thirty-four no-intervention volunteers completed the MAM twice. The MAM responses were analyzed with item response theory methods; t tests were used to compare responses across test occasions. Paired t tests revealed significant changes in the intervention group at both 2 weeks and 2 months, with an effect size of 0.90 and a responsiveness index of 5.62 at discharge. At 2 weeks and at discharge, 57% and 80% of participants, respectively, showed gains greater than the minimal clinically important difference. Participants in the no-intervention group showed no significant change. The MAM responses revealed significant and clinically important changes following intervention. The MAM shows promise as a self-report measure of the effectiveness of physical therapy intervention.