Development of a computerized adaptive testing system of the Fugl-Meyer motor scale in stroke patients

Abstract

Objective: To develop a computerized adaptive testing system of the Fugl-Meyer motor scale (CAT-FM) to efficiently and reliably assess motor function in patients with stroke.

Design: First, a simulation study was used to develop and examine the psychometric properties of the CAT-FM. Second, a field study was employed to determine the administration efficiency of the CAT-FM.

Setting: One medical center and 1 teaching hospital.

Participants: Patients' responses (n=301) were used for the simulation study; 49 patients participated in the field study.

Interventions: Not applicable.

Main outcome measures: The 2 CAT-FM item banks (upper extremity and lower extremity) include 37 items from the original Fugl-Meyer scale. The reliability, validity, and responsiveness of the CAT-FM were determined by the simulation study.

Results: Two stopping rules (reliability ≥0.9 or an increase of reliability <.01 after testing an item) were used. The simulation study showed that the CAT-FM had high reliability (≥.93 for upper-extremity and lower-extremity subscales) and concurrent validity (Pearson r≥.91 for the upper-extremity and lower-extremity subscales and motor scale). The responsiveness was moderate (standardized response mean for the upper extremity=.67, lower extremity=.79, and motor=.77) for the 226 patients who completed both assessments at 14 and 90 days after stroke. The field study found that, on average, the time needed to administer the CAT-FM was 242 seconds with 4.7 items.

Conclusions: The CAT-FM is an efficient, reliable, valid, and responsive clinical tool for assessing motor function in patients with stroke.