Functional Independence Measure (FIM)

Abstract

The Functional Independence Measure (FIM) is a standardized, 18-item assessment scale developed by Keith, Granger, and Hamilton in 1987. Its primary function is to measure the severity of disability and quantify the level of assistance required for patients in rehabilitation settings. The FIM utilizes a 7-point ordinal scale to score performance across six major domains: Self-care, Sphincter control, Mobility (Transfers and Locomotion), Communication, and Social Cognition, providing a uniform system for tracking functional recovery and evaluating rehabilitation outcomes over time.

Keywords

Functional Independence Measure, FIM, rehabilitation, functional assessment, Activities of Daily Living (ADL), self-care, mobility, social cognition, disability scale, outcome measure.

Authors

Carl V. Granger, Betty B. Hamilton, Robert A. Keith, et al.

Purpose

The principal purpose of the Functional Independence Measure is to establish a standardized, multidisciplinary metric for assessing the burden of care required by an individual following illness or injury. By quantifying functional limitations, the FIM allows clinicians to objectively measure the severity of a patient’s disability and determine the necessary resources for effective care.

The scale is a crucial instrument for longitudinal monitoring, enabling clinicians to track changes in functional independence throughout a patient’s course of treatment. It is widely used to compare outcomes across different patient groups, evaluate the effectiveness of specific rehabilitation interventions, and inform critical decisions regarding discharge planning and long-term care needs.

Construct

The core construct measured by the FIM is functional independence, which encompasses both motor and cognitive performance in daily life activities. The FIM is designed to assess what the individual actually does, rather than what they theoretically could do (capacity). The 18 items are categorized into six functional areas, reflecting the necessary skills for independent living.

The assessment utilizes a 7-level ordinal scale that explicitly defines the level of assistance needed from another person—ranging from complete independence (score 7) to total assistance (score 1). This focus on the need for a helper makes the FIM a direct measure of the patient’s functional burden on caregivers and the healthcare system.

Validity

The FIM demonstrates strong construct validity, supported by its established relationships with other recognized scales measuring functional status. It has been shown to correlate positively with measures such as the Barthel Index and the Katz Activities of Daily Living Scale, confirming that it accurately captures the intended domain of functional dependence.

Crucially, the FIM exhibits sensitivity to change, meaning it is responsive enough to detect meaningful improvements or deterioration in a patient’s functional status over time. This sensitivity makes it highly suitable for use as an outcome measure in medical rehabilitation research and clinical practice, ensuring that observed changes reflect genuine modifications in the patient’s ability to perform daily tasks.

Reliability

The FIM is characterized by high psychometric reliability, confirming its consistency and stability across different administrations and raters. The scale demonstrates good interrater reliability, which is essential given its clinician-administered nature. Studies, including those by Keith et al. (1987), report robust Intraclass Correlation Coefficients (ICCs) ranging from 0.80 to 0.95, indicating strong agreement among different trained assessors.

Furthermore, the FIM possesses good test-retest reliability, with ICCs generally ranging from 0.75 to 0.90. This indicates that the scores remain stable when the patient’s underlying functional status has not changed, reinforcing the consistency of the measure over short periods. Quantitative reviews, such as that by Ottenbacher et al. (1996), affirm the overall high reliability of the instrument.

Factor Analysis

Factor analysis of the 18 FIM items consistently supports a two-factor model, rather than the six original conceptual domains. These two empirically derived factors represent distinct aspects of functional recovery.

The first factor is the Motor Subscale, which typically accounts for the majority of the variance and includes items related to Self-care, Sphincter control, Transfers, and Locomotion. The second factor is the Cognitive Subscale, which includes items related to Communication and Social cognition. This clear separation of motor and cognitive functioning allows clinicians to track recovery in these two major areas independently.

Instrument

Test Type: Clinician-administered, Observational Performance Scale

Format: 18 items rated on a 7-point ordinal scale (level of assistance required by a helper)

Language Available: English (Original), widely translated into numerous languages including Spanish, French, German, and Japanese.

Population Group: Patients undergoing medical rehabilitation.

Age Group: Typically utilized for adults and adolescents; a modified pediatric version (WeeFIM) is available for younger populations.

Population Details: Individuals with significant functional deficits, commonly those recovering from stroke, spinal cord injury, traumatic brain injury, multiple sclerosis, or major orthopedic trauma.

Test Methodology: Structured observational assessment combined with interview, conducted by a trained healthcare professional. The score reflects the lowest level of assistance required for the patient to safely perform the task.

Keywords

disability assessment, motor function, cognitive function, activities of daily living, burden of care, psychometrics, Intraclass Correlation Coefficient, outcome measurement, rehabilitation outcomes.

Authors

Author ORCID Identifier: Not specified in source.

Affiliation Email addresses: Managed by Uniform Data System for Medical Rehabilitation (UDSMR).

Correspondence Address: Managed by Uniform Data System for Medical Rehabilitation (UDSMR).

Permissions & Fee and Test Year

The Functional Independence Measure is a proprietary instrument. Usage requires formal licensing, training, and certification, typically managed by the Uniform Data System for Medical Rehabilitation (UDSMR), which is now part of the organization overseeing US medical rehabilitation data.

Test Year: 1987 (Initial conceptualization and publication).

Reference’s

1. Hamilton, BB., Granger, CV., Sherwin, FS., et al. (1987). A uniform national data system for medical rehabilitation. In: Fuhrer MJ, ed. Rehabilitation outcomes: analysis and measurement. Baltimore: Paul H. Brookes, 137–147.
2. Granger, CV., Cotter, AC., Hamilton, BB., et al. (1990). Functional assessment scales: a study of persons with multiple sclerosis. Arch Phys Med Rehabil, 71:870–875.
3. Granger, CV., Hamilton, BB., Keith, RA., et al. (1986). Advances in functional assessment for medical rehabilitation. Top Geriatr Rehabil, 1:59–74.
4. Ottenbacher, KJ., Hsu, Y., Granger, CV., et al. (1996). The reliability of the Functional Independence Measure: a quantitative review. Arch Phys Med Rehabil, 77:1226–1232.
5. McDowell, Ian. (2006). Measuring Health: A Guide to Rating Scales and Questionnaires, Third Edition. OXFORD UNIVERSITY PRESS.

Items of the Functional Independence Measure (FIM)

SELF-CARE

Eating. Includes use of suitable utensils to bring food to mouth, chewing and swallowing, once meal is appropriately prepared.

Grooming. Includes oral care, hair grooming, washing hands and face, and either shaving or applying makeup.

Bathing. Includes bathing the body from the neck down (excluding the back), either tub, shower or sponge/bed bath. Performs safely.

Dressing—Upper Body. Includes dressing above the waist as well as donning and removing prosthesis or orthosis when applicable.

Dressing—Lower Body. Includes dressing from the waist down as well as donning or removing prosthesis or orthosis when applicable.

Toileting. Includes maintaining perineal hygiene and adjusting clothing before and after toilet or bed pan use. Performs safely.

SPHINCTER CONTROL

Bladder Management. Includes complete intentional control of urinary bladder and use of equipment or agents necessary for bladder control.

Bowel Management. Includes complete intentional control of bowel movement and use of equipment or agents necessary for bowel control.

MOBILITY

Transfers: Bed, Chair, Wheelchair. Includes all aspects of transferring to and from bed, chair, and wheelchair, and coming to a standing position, if walking is the typical mode of locomotion.

Transfer: Toilet. Includes getting on and off a toilet.

Transfers: Tub or Shower. Includes getting into and out of a tub or shower stall.

LOCOMOTION

Walking or Using Wheelchair. Includes walking, once in a standing position, or using a wheelchair, once in a seated position, on a level surface.

Check most frequent mode of locomotion. If both are about equal, check W and C. If initiating a rehabilitation program, check the mode for which training is intended.

• ( ) W = Walking
• ( ) C = Wheelchair

Stairs. Goes up and down 12 to 14 stairs (one flight) indoors.

COMMUNICATION

Comprehension. Includes understanding of either auditory or visual communication (e.g. writing, sign language, gestures).

Check and evaluate the most usual mode of comprehension. If both are about equally used, check A and V.

• ( ) A = Auditory
• ( ) V = Visual

Expression. Includes clear vocal or non-vocal expression of language. This item includes both intelligible speech or clear expression of language using writing or a communication device.

Check and evaluate the most usual mode of expression. If both are about equally used, check V and N.

• ( ) V = Vocal
• ( ) N = Nonvocal

SOCIAL COGNITION

Social Interaction. Includes skills related to getting along and participating with others in therapeutic and social situations. It represents how one deals with one’s own needs together with the needs of others.

Problem Solving. Includes skills related to solving problems of daily living. This means making reasonable, safe, and timely decisions regarding financial, social and personal affairs and initiating, sequencing and self-correcting tasks and activities to solve the problems.

Memory. Includes skills related to recognizing and remembering while performing daily activities in an institutional or community setting. It includes ability to store and retrieve information, particularly verbal and visual. A deficit in memory impairs learning as well as performance of tasks.

DESCRIPTION OF THE LEVELS OF FUNCTION AND THEIR SCORES

INDEPENDENT—Another person is not required for the activity (NO HELPER).

7 Complete Independence—All of the tasks described as making up the activity are typically performed safely, without modification, assistive devices, or aids, and within a reasonable time.

6 Modified Independence—Activity requires any one or more than one of the following: an assistive device, more than reasonable time, or there are safety (risk) considerations.

DEPENDENT—Another person is required for either supervision or physical assistance in order for the activity to be performed, or it is not performed (REQUIRES HELPER).

MODIFIED DEPENDENCE—The subject expends half (50%) or more of the effort. The levels of assistance required are:

5 Supervision or setup—Subject requires no more help than standby, cuing or coaxing, without physical contact. Or, helper sets up needed items or applies orthoses.

4 Minimal contact assistance—With physical contact the subject requires no more help than touching, or subject expends 75% or more of the effort.

3 Moderate assistance—Subject requires more help than touching, or expends half (50%) or more (up to 75%) of the effort.

COMPLETE DEPENDENCE—The subject expends less than half (less than 50%) of the effort. Maximal or total assistance is required, or the activity is not performed. The levels of assistance required are:

2 Maximal assistance—Subject expends less than 50% of the effort, but at least 25%.

1 Total assistance—Subject expends less than 25% of the effort.