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Keynotes

KEYNOTE 2
Rehabilitation Measures

Gale Whiteneck, Ph.D.

The field of rehabilitation has been guided in its selection of injury outcomes by an evolving series of conceptual models of disability. These include the International Classification of Impairments, Disabilities and Handicaps (ICIDH) proposed by the World Health Organization (WHO) in 1980, two models proposed by the Institute of Medicine in 1991 and 1997, and the WHO’s 1999 revision of its model, titled “International Classification of Functioning and Disability (ICIDH-2).” When applied to injury, all of these conceptual models differentiate three levels of injury outcomes: the organ level, the person level, and the societal level. Using the terminology of the ICIDH-2, the organ level is labeled “body functions and structure” and problems with the physiological or psychological functions of body systems or the loss of anatomic parts of the body are referred to as impairments. The person level is labeled “activity” and difficulties an individual may have in the performance of tasks are called “activity limitations.” The societal level is labeled “participation” and problems an individual may have in the manner or extent of involvement in life situations are called “participation restrictions.” The ICIDH-2 recognizes that contextual factors are an integral component of the model and it includes a classification of environmental factors along with the other three dimensions. From these conceptual models, four categories of rehabilitation measures have emerged.

First, impairment measures quantify the performance of organ systems and are used to assess the extent to which organ system functions recover after injury. Many specific impairment measures exist and they typically focus on the functioning of an individual organ or organ system. Examples include “Standards for Neurological Classification of Spinal Injury Patients” (American Spinal Injury Association, 1982) to quantify the extent of motor and sensory preservation after spinal cord injury, and the Glasgow Coma Scale (Teasdale and Jannett, 1994) to quantify the degree of alteration of consciousness after traumatic brain injury. Clearly, the most appropriate impairment measure to apply depends upon the organ system injured.

Second, measures of activities of daily living (ADL) quantify the degree of assistance needed in the performance of routine personal tasks and are used to measure functional independence after injury. There is a long history of the proliferation of many ADL measures within the field of rehabilitation, which has culminated in the Functional Independence Measure (FIM) that is currently used in the majority of rehabilitation facilities to document improvements in ADL independence occurring during rehabilitation (State University of New York, 1993). The FIM is an 18-item instrument measuring the amount of assistance an individual needs in order to perform activities of self-care, mobility, sphincter control, communication, and social cognition on a 7-point scale from complete independence to complete dependence. The FIM can be assessed by a trained clinician in any discipline and applied to rehabilitation patients with any diagnosis. This has resulted in one standard instrument being used in most inpatients’ rehabilitation setting.

Third, participation measures quantify the degree to which an individual is an active and productive member of society and they are used to assess the extent of community reintegration after injury. Participation measurement is a more recent, but growing phenomenon within rehabilitation. The Community Integration Questionnaire (Willer et al., 1993) has been used in traumatic brain injury rehabilitation and the Craig Handicap Assessment and Reporting Technique (CHART) (Whiteneck et al., 1992) has been used in a variety of rehabilitation research efforts to document the extent of community reintegration after injury or disability. CHART was specifically designed to be a practical and objective measure of the six dimensions of handicap (participation) identified by the ICIDH. The six-dimensions are each scored on 100-point scales, normalized so that a score of 100 reflects the expected level of participation in the general population. The cognitive independence sub-scale is assessed by the amount of supervision an individual needs at home and away from home. Physical independence is assessed by the hours of paid and unpaid assistance utilized per day for physical tasks. Mobility is assessed by hours out of bed, days out of the house, and nights away from home. Occupation is assessed by the hours per week an individual spends in such activities as working, schooling, and active homemaking. Social integration is assessed by the extent of regular contacts with family, friends, business or organizational associates, and strangers. Economic self-sufficiency is assessed by the total family income from all sources minus non-reimbursed medical expenses.

Fourth, environmental measures quantify the degree to which physical, social, and attitudinal environmental factors act as either barriers or facilitators to full participation and these measures are used to document the influence of external factors on performance. The need for environmental measures has been highlighted by the new paradigm of disability (often referred to as the social model) that recognizes the key role of the environment (along with disability) in determining the extent of participation in society after injury. The Craig Hospital Inventory of Environmental Factors (CHIEF) is a new brief measure of the physical, attitudinal, and policy barriers encountered by people with disabilities in their environments (Craig Hospital, 2000). The CHIEF quantifies the frequency with which 25 environmental barriers are encountered and the magnitude of problems they create. The CHIEF has been used to demonstrate that people encounter more problematic and more frequent barriers with disabilities than people without disabilities and to differentiate the nature of environmental barriers encountered by individuals with different types of disability.

In addition to the four types of rehabilitation measures emerging from the conceptual models of disability, two additional outcomes are important after injury and are utilized within rehabilitation: health status and subjective well-being. The fifth category of rehabilitation measures falls under the rubric of health status measures and they quantify the degree to which medical complications and secondary conditions are avoided over the life span after injury (Whiteneck et al., 1992). In addition to survival measures, measures of morbidity frequently utilized include the annual days of re-hospitalization after rehabilitation and the incidence rates of major secondary conditions (e.g., the number of pressure sores occurring after spinal cord injury).

In an effort to recognize the equal importance of the perspective of the injured individual to the perspective of the clinician, subjective well-being measures are being utilized within rehabilitation to assess self-perceived quality of life. Subjective well-being can be defined as the degree to which people have positive thoughts and feelings about their lives and are often measured through self-reports of life satisfaction. One currently popular measure of subjective well-being is the Satisfaction with Life Scale (Diener, 1994), which asks individuals the extent of their agreement or disagreement on a seven-point scale with five statements regarding life satisfaction.

Taken together, these six types of rehabilitation measures can be utilized for the comprehensive assessment of the consequences of injury and the success of rehabilitation. Diagnostic-specific measures can assess organ system impairments; activity limitations can be assessed by FIM; participation restrictions can be assessed by CHART; environmental barriers can be assessed by CHIEF; health status can be assessed by survival, days re-hospitalized, and complication rates; and subjective well-being can be assessed by the Satisfaction with Life Scale. The field of rehabilitation offers a unique perspective on injury research: it offers a multi-dimensional conceptualization and measurement of outcome. It highlights the importance of societal participation as well as functional performance, recognizes the influence of the environment on outcomes, and values the subjective perceptions of the people injured as well as the assessments of clinicians.

References