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Original report

Validity and reliability of the de Morton Mobility Index in the subacute hospital setting in a geriatric evaluation and management population

doi: 10.2340/16501977-0626

Open access


OBJECTIVE: To investigate the clinimetric properties of the de Morton Mobility Index (DEMMI) in a Geriatric Evaluation and Management (GEM) population.
DESIGN: A longitudinal validation study (n = 100) and inter-rater reliability study (n = 29) in a GEM population.
Patients: Consecutive patients admitted to a GEM rehabilitation ward were eligible for inclusion.
METHODS: At hospital admission and discharge, a physical therapist assessed patients with physical performance instruments that included the 6-metre walk test, step test, Clinical Test of Sensory Organization and Balance, Timed Up and Go test, 6-minute walk test and the DEMMI. Consecutively eligible patients were included in an inter-rater reliability study between physical therapists.
RESULTS: DEMMI admission scores were normally distributed (mean 30.2, standard deviation 16.7) and other activity limitation instruments had either a floor or a ceiling effect. Evidence of convergent, discriminant and known groups validity for the DEMMI were obtained. The minimal detectable change with 90% confidence was 10.5 (95% confidence interval 6.1–17.9) points and the minimally clinically important difference was 8.4 points on the 100-point interval DEMMI scale.
CONCLUSION: The DEMMI provides clinicians with an accurate and valid method of measuring mobility for geriatric patients in the subacute hospital setting.


Natalie A. de Morton, Kylie Lane


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Volume 42, Issue 10

DOI: 10.2340/16501977-0626

Pages: 956-961

View at PubMed