Impairment-specific dimensions within the Functional Independence Measure.
OBJECTIVE
The analyses presented in this article were intended to seek more fine-grained impairment-specific dimensions beyond the motor and cognitive dimensions of the Functional Independence Measure (FIMSM).


METHODS
The study used factor analysis within 20 categories of impairment to test the hypotheses that FIM items can be grouped according to functional areas of the body and that these item groupings differ depending on the patient's impairment.


METHODS
Data from 93,829 patients discharged in 1992 from 252 free-standing rehabilitation hospitals and units were obtained from the Uniform Data System for Medical Rehabilitation.


RESULTS
In 18 of 20 impairment categories, factor analyses of patients admission FIM scores showed impairment-specific FIM dimensions. Four impairments had a 3-dimensional factor structure, and 14 had a 4-dimensional structure. The impairment-specific dimensions were always nested within the motor-FIM subscale. Reliability coefficients for subscales based on these dimensions ranged from .74 to .97. The subscales appear to cluster FIM items by the area of body involved, neurological level, or relative energy consumption.


CONCLUSIONS
The FIM can be viewed as a multilayered multidimensional measure of human function. The impairment-specific dimensions, at an intermediate layer, provide insight about the causal linkage between the impairment and resultant patterns of disability. Impairment-specific subscales are relevant to those clinical or research applications where the type of disability needs to be more closely related to impairment.
Stineman
M G
MG
Department of Rehabilitation Medicine, University of Pennsylvania, Philadelphia, USA.
Jette
A
A
Fiedler
R
R
Granger
C
C
D000203:Activities of Daily Living; D003071:Cognition; D004185:Disability Evaluation; D005163:Factor Analysis, Statistical; D006801:Humans; D008954:Models, Biological; D009048:Motor Skills; D012046:Rehabilitation; D012047:Rehabilitation Centers