Concurrent validity of mobility disability scale among community-dwelling individuals

Purpose: A new Mobility Disability Scale (MDS) has been developed to assess the level of mobility disability among community-dwelling individuals. For it to be used effectively, a systematic evaluation of the psychometric properties is required. This study was conducted to determine the concurrent validity of the MDS among community-dwelling individuals, as compared to the Functional Independence Measure (FIM) and Functional Assessment Measure (FAM). Method: Based on the survey of a semi-urban community, purposive sampling was used to select 52 individuals with mobility disability. All of them were evaluated using MDS and FIM FAM scales at the same time. Spearman’s Rank correlation coefficient was used to analyse the correlation of MDS scores with the FIM FAM scale scores. Results: MDS scores had statistically significant negative correlation with FIM FAM total scale scores (r= -0.711) and the correlation was stronger when analysed with the mobility components of FIM FAM scales (r= -0.724). Conclusion: The MDS possesses moderate concurrent validity with an existing functional scale. This indicates that it may be a suitable tool to quantify the level of mobility disability in persons with disability living in community. Limitation: The psychosocial domain, though important, could not be compared with any gold standard measures due to unavailability of suitable scales.