Comparison of the sensitivity to change of the Functional Independence Measure with the Assessment of Motor and Process Skills within different rehabilitation populations.

PURPOSE

To determine whether there was a difference in the sensitivity to change of the subscales of the Functional Independence Measure and the Assessment of Motor and Process Skills within three different post-acute inpatient rehabilitation populations.

MATERIAL AND METHODS

We conducted retrospective chart review of patients consecutively admitted to inpatient rehabilitation units, with both admission and discharge Functional Independence Measure and Assessment of Motor and Process Skills scores. A total of 276 participants were included and categorized into diagnostic groups (orthopedic, oncology, and geriatric). Within group, sensitivity to change was evaluated for the subscales of each measure by calculating the difference in standardized response means (SRM) and 95% confidence intervals (CI).

RESULTS

The Functional Independence Measure motor subscale was more sensitive to change than the Assessment of Motor and Process Skills in the orthopedic and geriatric groups (SRM = 1.53 [95% CI 0.93, 2.3] and 0.65 [95% CI 0.3, 1.02], respectively) but not in the oncology group (SRM = 0.42 [95% CI -0.2, 1.04]). For the cognitive subscales, the Assessment of Motor and Process Skills was more sensitive to change than the Functional Independence Measure in all three groups (SRM = 0.38 [95% CI 004, 0.74], 0.65 [95% CI 0.45, 0.90], and 1.15 [95% CI 0.77, 1.69] for orthopedic, geriatric, and oncology, respectively).

CONCLUSIONS

The Functional Independence Measure is a mandated measure for all rehabilitation units in Canada. As the cognitive subscale of the Assessment of Motor and Process Skills is more sensitive to change than the Functional Independence Measure, we recommend also administering the Assessment of Motor and Process Skills to better detect changes in the cognitive aspect of function. Implications for rehabilitation When deciding between the Functional Independence Measure or the Assessment of Motor and Process Skills, it is important to consider whether patients' functional status is expected to change similarly or differently. The difference in sensitivity to change between the subscales of the two outcome measures varies with the characteristics of change (similar or different) in patients' functional status. We recommend using the Assessment of Motor and Process Skills, along with the Functional Independence Measure, for patients who are expected to make similar amounts of change in functional status, as the cognitive subscale of the Assessment of Motor and Process Skills is more sensitive to change and can better detect changes in the cognitive aspect of functioning. For patients whose functional status are expected to change differently (diverse diagnoses), the Functional Independence Measure may be more useful as the motor subscale was more sensitive to change when comparing between rehabilitation populations.