Clinical Outcome Variables Scale: A retrospective validation study in patients after stroke.

OBJECTIVE The construct, predictive and longitudinal validity of the Clinical Outcome Variables Scale (COVS), an assessment of functional mobility, was examined in relation to measures of functional disability (Functional Independence Measure (FIMTM)), balance (Berg Balance Scale (BBS)) and length of stay in inpatient stroke rehabilitation. METHODS Associations between admission and discharge scores on each measure were examined retrospectively for 134 patients admitted for inpatient stroke rehabilitation. The association between admission scores and length of stay was tested using a simple linear regression. Paired t-tests and standardized response means were calculated to examine longitudinal validity. RESULTS COVS scores were correlated with FIM and BBS scores at admission (rho = 0.823 and 0.895, respectively) and discharge (rho = 0.771 and 0.895, respectively). Admission COVS, FIM and BBS scores were correlated with length of stay (rho = -0.61, -0.69 and -0.61, respectively; p < 0.01). A significant (p < 0.01) linear association was demonstrated between admission scores and length of stay. All measures demonstrated significant change over time. Standardized response means were 1.23, 1.16 and 1.36 for the COVS, BBS and FIM, respectively. CONCLUSION Within a subset of rehabilitation patients with stroke, the COVS demonstrated construct, predictive and longitudinal validity. The COVS provides a comprehensive assessment of functional mobility and should be evaluated further for its usefulness in stroke rehabilitation.