Interrater reliability of the 7-level functional independence measure (FIM)

Area of Science:

• Rehabilitation Medicine
• Clinical Assessment
• Health Services Research

Background:

• The Functional Independence Measure (FIM) is a standardized tool for assessing patient disability and outcomes in medical rehabilitation.
• Uniform assessment is crucial for tracking patient progress and facility performance.

Purpose of the Study:

• To evaluate the interrater reliability of the 7-level Functional Independence Measure (FIM) in a clinical setting.
• To establish the consistency of FIM scoring among different clinicians.

Main Methods:

• Data collected from 1018 patients across 89 US inpatient rehabilitation facilities between January 1988 and June 1990.
• Interrater reliability assessed using intraclass correlation coefficients (ICC) for total, domain, and subscale scores.
• Item-level agreement analyzed using unweighted Kappa coefficients.

Main Results:

• High overall FIM interrater reliability was observed, with total score ICC at 0.96.
• Motor domain ICC was 0.96, and cognitive domain ICC was 0.91.
• Subscale scores ranged from 0.89 (social cognition) to 0.94 (self-care), and item Kappa coefficients ranged from 0.53 (memory) to 0.66 (stair climbing).
• A subset of 24 facilities meeting specific reliability criteria showed even higher ICC and Kappa coefficients.

Conclusions:

• The 7-level Functional Independence Measure (FIM) is a reliable instrument for assessing patient disability and functional outcomes in inpatient medical rehabilitation.
• Trained and tested clinicians can consistently apply the FIM scale, ensuring data uniformity.
• The findings support the use of FIM for standardized patient evaluation in rehabilitation settings.