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 Isaac, L. (2016). The
Disability Rating Scale. The Center for Outcome Measurement
in Brain Injury. http://www.tbims.org/
combi/drs ( accessed
This citation is for the COMBI web material. Dr. Isaac is
not the scale author for the DRS.
to the Disability Rating Scale
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."
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.
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.
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.
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.
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.