The Mobility Scale for Acute Stroke Patients: concurrent validity

Abstract

Objective: A new scale, the Mobility Scale for Acute Stroke Patients (MSAS), was developed to specifically discriminate between the lower levels of mobility found in acute stroke patients in the first two weeks post onset. The aim of this study was to investigate the concurrent validity of this new scale with other established scales. Main outcome measures: Concurrent validity was assessed with respect to four other well-validated measures: Motor Assessment Scale (MAS), Functional Ambulation Classification system (FAC), Functional Independence Measure (FIM), and Barthel Index (BI). The measures selected for comparison contained items similar to those in the MSAS. Subjects: From a total of 539 patients who were admitted over a two-year period with a primary diagnosis of stroke, 106 satisfied the criteria for inclusion in this study. Results: The MSAS was found to have a high level of concurrent validity ( r > 0.80) when the total score was correlated with the total scores of the MAS, FAC, FIM (mobility and ADL) and BI. A high level of association was found between the nonbed mobility items (sit to stand, stand and walk) of the MSAS and the mobility items (toileting, transfers, walk and stairs) of the FIM and BI. There was a weaker association between the MSAS items and the ADL items (activities of daily living) of the BI and FIM. Conclusion: A new scale designed specifically for acute stroke patients was found to have a high degree of concurrent validity when compared with four other scales containing similar items.