ABSTRACT
OBJECTIVE: To evaluate the reliability and validity of accelerometry for measuring upper-extremity rehabilitation outcome. DESIGN: Validation study. SETTING: Data recorded in the community. PARTICIPANTS: Consecutive Constraint-Induced Movement therapy (CIMT) patients (n = 10) and volunteer community residents with stroke (n = 10). All participants were more than 1 year poststroke and had mild to moderate motor impairment of the more affected arm. INTERVENTION: All study participants were asked to wear accelerometers outside the laboratory for 3 days immediately before and after treatment, or for an approximately equivalent no-treatment period (controls). MAIN OUTCOME MEASURES: Participants wore an accelerometer on each arm, the chest, and the more affected leg and completed the Motor Activity Log (MAL), which is a semistructured interview of real-world arm use. RESULTS: Test-retest reliability of transformed accelerometer recordings was greater than .86. There was also a large increase in the ratio of transformed more- to less-impaired arm recordings in CIMT therapy patients (d' = 0.9, P < .05), while there was no change for controls. The correlation between this parameter and the MAL was .74 (P < .001). CONCLUSIONS: Accelerometry provides an objective, real-world index of upper-extremity rehabilitation outcome and has good psychometric properties.
