Dr. Linda Isaac, PhD Director, Rehabilitation Research Center Santa Clara Valley Medical Center
Assistant Professor (Affiliated) Stanford University, School of Medicine Department of Orthopedic Surgery
Citation Wright, J. (2000). The Disability Rating Scale. The Center for Outcome Measurement in Brain Injury. http://www.tbims.org/ combi/drs ( accessed
*Note: This citation is for the COMBI web material. Mr. Wright is not the scale author for the DRS.
Introduction to the Disability Rating Scale
The Disability Rating Scale (DRS) was developed and tested with older juvenile and adult individuals with moderate and severe traumatic brain injury (TBI) in an inpatient rehabilitation setting. One advantage of the DRS is its ability to track an individual from coma to community. Measurement across a wide span of recovery is possible because various items in this scale address all three World Health Organization categories: impairment, disability and handicap (WHO,1980). The first three items of the DRS ("Eye Opening," "Communication Ability" and "Motor Response") are a slight modification of the Glasgow Coma Scale (Teasdale and Jennett, 1974), and reflect impairment ratings. Cognitive ability for "Feeding," "Toileting" and "Grooming" reflect level of disability. The "Level of Functioning" item is the modification of a measure used by Scranton et al. (1970), and reflects handicap, as does the last item, "Employability."
The maximum score a patient can obtain on the DRS is 29 (extreme vegetative state). A person without disability would score zero. The DRS rating must be reliable, i.e., obtained while the individual is not under the influence of anesthesia, other mind-altering drugs, recent seizure, or recovering from surgical anesthesia.
The scale is intended to measure accurately general functional changes over the course of recovery. Rappaport et al. (1989) obtained DRS scores on 63 TBI individuals at rehabilitation admission, discharge, and up to ten years post injury (median = nine years). Results showed a proportional change in DRS scores based on time elapsed between injury and admission to rehabilitation. A significantly greater improvement was seen in the early admission group. Others have also demonstrated the utility of the DRS to make comparisons across time (Hall & Cope, 1985; Novack et al., 1991; Fryer and Haffey, 1987). The relative sensitivity of the DRS was addressed by Hall et al. (1985). In a comparison with the Glasgow Outcome Scale (Jennett et al., 1981), 71% of TBI individuals showed improvement on DRS vs. 33% on GOS.
The DRS has been proven reliable and valid, as addressed in more detail in following sections. It can be self-administered or scored through interview with the client or the family member. The ease of scoring and the brevity of the scale are compelling reasons for its popularity. Scoring time can range from 30 seconds (if one is very familiar with the scale and the client) to 15 minutes, assuming the rater must interview the client/family and seek additional information from available staff.
An additional advantage is the ease and brevity with which information can be obtained by phone interview. Although not optimum, DRS ratings can even be obtained by medical record review retrospectively in certain cases. Another advantage of the DRS is that expertise in the field is not needed to complete it accurately.
A limitation of the DRS is its relative insensitivity at the low end of the scale (mild TBI) and its inability to reflect more subtle but sometimes significant changes in an individual within a specific, limited window of recovery.