Abstract
Background: Balance and gait problems are common and progressive in dementia. Mobility aid use in people with dementia increases the likelihood of falls three-fold. An assessment tool to quantify mobility aid safety in people with dementia does not currently exist. The objectives of this study were: 1) to develop a tool for the evaluation of physical function and safety with use of a 4-wheeled walker in people with dementia, and 2) to evaluate its construct and criterion validity, inter-rater and test-retest reliability and minimal detectable change.Methods: Healthcare professionals (HCP) experienced in care and rehabilitation of people with dementia participated in focus groups for item generation of the new tool, entitled The Safe Use of Mobility Aid Checklist (SUMAC). The SUMAC evaluates physical function (PF) and safe use of the equipment (EQ) on nine tasks of daily life. Ten individuals with dementia using a 4-wheeled walker were recorded performing the tasks within the SUMAC. Reliability was evaluated by having five HCP score participant videos on two occasions. Inter-rater and test-retest reliability was assessed using intra-class correlation coefficients (ICC). Construct validity was evaluated using scores determined by a consensus panel compared to the individual HCP scores using Spearman’s rank-order correlations. Criterion validity was assessed between SUMAC-PF and the Performance-Oriented Mobility Assessment (POMA) gait subscale using Spearman’s rank-order correlations. Results: Three focus groups (n=17) were completed and these generated a tool comprised of nine tasks and the components within each task that the clinicians would observe for physical function and safe use. Inter-rater reliability was statistically significant for the SUMAC-PF (ICC=0.92, 95%CI (0.81, 0.98), p<0.001) and SUMAC-EQ (ICC=0.82, 95%CI (0.54, 0.95), p<0.001). Test-retest reliability was also statistically significant for the SUMAC-PF (ICC=0.89, 95%CI (0.81, 0.94), p<0.001) and SUMAC-EQ (ICC=0.88, 95%CI (0.79, 0.93), p<0.001). The POMA gait subscale correlated strongly with the SUMAC-PF (r=0.84), but not EQ (r=0.39).Conclusions: Each of the scores of the SUMAC, physical function and safe use of the equipment, demonstrated content validity, strong inter-rater and test-retest reliability and strong criterion and concurrent validity for the assessment of mobility aid safety in people with dementia.