The responsiveness and predictive validity of the de Morton Mobility Index in geriatric rehabilitation

Introduction:The de Morton Mobility Index (DEMMI) is a unidimensional clinical instrument proven reliable and valid for measuring mobility in the elderly, but its responsiveness has not been evaluated when applying the methodology recommended by COSMIN. Purpose:To evaluate the responsiveness and the predictive validity of the DEMMI. Materials and methods:Elderly people, referred for municipality-based rehabilitation, were consecutively included. Eight hypotheses regarding the relationship between the change scores in the DEMMI and other functional measures of mobility were tested by assessing the participants before and after rehabilitation. Three months after completing the rehabilitation, the participants' functional status was evaluated. Results:250 elderly people (mean age 85 years, 63% women) were included. The change scores in the DEMMI and the other measures correlated (r = 0.422 to 0.547), but only three out of the eight hypotheses were confirmed. A DEMMI score of less than 48 and less than 67 can predict inability of ambulating close to the participant's residence and using public transport, respectively. Conclusions:We found a moderate responsiveness and a high predictive validity of the DEMMI score. The DEMMI appears to be an appropriate instrument for monitoring change in mobility and predicting functional status among elderly patients undergoing rehabilitation.

Automated summary

This study evaluated the responsiveness and predictive validity of the DEMMI. The results showed moderate responsiveness and high predictive validity of the DEMMI score. The DEMMI score can be used to monitor mobility changes and predict functional status in elderly patients undergoing rehabilitation.