To examine the effect of wearing an accelerometer (without provision of feedback) on the mobility of older rehabilitation inpatients, using the locomotion component of the FIM at admission and discharge.

A retrospective matched cohort study of patients aged >60 years admitted to a rehabilitation unit between 1 January 2008 and 1 January 2009.

The exposed group was 17 patients who had worn an accelerometer daily during their rehabilitation stay. These patients were matched with 17 controls (the unexposed group) identified from the unit database using the following variables: age (within 5 years), sex, admission Functional Independence Measure (locomotion) score and reason for admission to rehabilitation.

The median length of stay, median FIM (locomotion) gain and median FIM (locomotion) efficiency for the two groups were compared using the Wilcoxon Signed Ranks Test.

There were no statistically significant differences between the two groups at baseline. There was a trend towards a greater FIM-locomotion gain in the accelerometer group (mean 2.88+/− 2.12, median 3.00) compared with the no-accelerometer group (mean 2.53+/− 2.07, median 3.00), but this did not reach statistical significance (p=0.08). There was no significant difference in the FIM-locomotion efficiency for the accelerometer group (mean 0.08 +/− 0.07, median 0.05) compared with the no accelerometer group(mean 0.01 +/− 0.09, median 0.06) (p= 0.33).

In the absence of feedback and goal setting, wearing a monitoring device does not significantly increase physical activity.