The Ohio Modified Arm Ability Test: Modification, Optimization, and Psychometric Evaluation

PURPOSE: The purpose of this study was to develop a reliable, valid, and time-efficient functional measure of upper-extremity (UE) motor ability.

RATIONALE: Stroke is a leading cause of UE impairment in adults, and limitations in UE motor ability negatively affect individual performance in meaningful activities. Commonly used measures of UE impairment and function are often time intensive, resource intensive, and repetitive. As stroke survivor prevalence increases, the need for efficient, effective functional measurement to measure treatment efficacy and set goals will continue to be a pressing need.

DESIGN: Secondary psychometric analysis of data obtained from a multicenter randomized controlled trial to evaluate and standardize the Ohio Modified Arm Motor Ability Test (OMAAT).

PARTICIPANTS: Applying the aforementioned study criteria, 41 participants were enrolled into the ETMS group and are included in this secondary analysis (24 men; mean age = 65 yr, standard deviation [SD] = 12.0; mean time since stroke onset = 92 days, SD = 52.3; 31 ischemic survivors with ischemic stroke; 21 participants with right-sided lesions).

METHOD: Data were obtained from a multicenter randomized clinical trial in which the measure was administered.

ANALYSIS: OMAAT items were optimized prior to psychometric evaluation. OMAAT reliability and validity were examined using internal consistency (Cronbach’s α, ordinal α, Gugiu’s bootstrap), dimensionality (latent parallel analysis, ordinal exploratory factor analysis, and convergent validity (correlations, Bland-Altman plots) measures.

RESULTS: Three independent estimates of internal consistency revealed excellent reliability. Cronbach’s α = .97 (95% CI [.95, .99]); ordinal α = .98 (95% CI [.97, .99]); Gugiu’s bootstrap = .97 (95% CI [.95, .98]). Latent parallel analysis and ordinal exploratory factor analysis support a unidimensional factor structure. All items had strong, positive loadings with this single factor. OMAAT convergent validity with the ARAT was .895.

DISCUSSION: These findings confirm OMAAT standardization, optimization, and relevance as a stroke assessment with utility as a clinical functional measure.

IMPACT STATEMENT: OMAAT provides a much-needed efficient, evidence-based method for the assessment of UE function among stroke survivors.