The Geriatric Depression Scale (GDS) is a 30-item self-report assessment designed specifically to identify depression in the elderly. The items may be answered yes or no, which is thought to be simpler than scales that use a five-category response set. It is generally recommended as a routine part of a comprehensive geriatric assessment. One point is assigned to each answer and corresponds to a scoring grid. A score of 10 or 11 or lower is the usual threshold to separate depressed from nondepressed patients. However, a diagnosisof clinical depression should not be made on the GDS results alone. Although the test has well-established reliability and validity, responses should be considered in conjunction with other results from a comprehensive diagnostic work-up. A short version of the GDS containing 15 questions has been developed. The GDS is also available in a number of languages other than English.
Purpose
Depression is widespread among elderly persons, affecting one in six patients treated in general medical practice and an even higher percentage of those in hospitals and nursing homes. Older people have the highest suiciderate of any group, and many medical problems common to older people may be related to, or intensified by, a depressive disorder. Recognition of the prevalence of depression among older people prompted the development of the geriatric depression scale in 1982-83. Yes/no responses are thought to be more easily used than the graduated responses found on other standard assessment scales such as the Beck Depression Inventory, the Hamilton rating scale for depression, or the Zung self-rating depression scale.
While it is not found in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) produced by the American Psychiatric Association, the GDS is widely recommended for clinical use and is included as a routine part of a comprehensive geriatric assessment. It is also increasingly being used in research on depression in the elderly.
Precautions
Depression scales are either interviewer-administered or by self-report means. The GDS is a self-report assessment developed in 1982 by J. A. Yesavitch and colleagues. A self-report assessment is easier and quicker to administer, though an interviewer-administered test is generally more sensitive and specific—another reason for using more than one tool to obtain an accurate diagnosis.
There is some controversy over whether the GDS is reliable for depression screening in individuals with mild or moderate dementia. Several studies have shown good agreement with observer ratings of depression, whether or not the patient had dementia. However, persons with dementia may deny symptoms of depression. It also appears that less educated people are more likely to score in the depressed range on the GDS 15-item short form. These caveats notwithstanding, the GDS can be usefully applied in general medical settings in combination with other clinical assessments, observation, and interviews with elder patient and their families.
Both symptom pattern and symptom severity must be considered when trying to identify depression. These dimensions are taken into account in the development of symptom scales and, while clinical judgment takes priority, a scale such as the GDS can help in identifying persons with depression, whether they are making satisfactory progress with treatment, or when they may need further assessment or referral.
Description
Yesavitch and his coworkers chose 100 statements that they determined were related to seven common characteristics of depression in later life. These included:
somatic concern
lowered affect(affect is the outward expression of emotion)
cognitive impairment
feelings of discrimination
impaired motivation
lack of future orientation
lack of self-esteem
The best 30 items were selected after administration of the 100 items to 46 depressed and normal elders. Those items were then administered to 20 elders without depression and 51 who were in treatment for depression. The test was 84% sensitive and 95% specific for a depression diagnosis. Repeated studies have demonstrated the value of GDS.
Examples of the questions in the GDS include:
Are you basically satisfied with your life?
Have you dropped many of your activities and interests?
Are you hopeful about the future?
Do you often get restless and fidgety?
Do you frequently get upset over little things?
Do you enjoy getting up in the morning?
A time frame should be specified for administration of the test, for example, "Answer these questions by thinking of how you've felt the past two weeks."
Results
A scoring grid accompanies the GDS. One point is given for each respondent's answer that matches those on the grid. For example, the grid response to "Are you basically satisfied with your life?" is "no." If the elderly person responds in the negative one point is scored; if the response is "yes," then no point is scored. For the 30-item assessment, a score of 0–9 is considered normal; 10–19 indicates mild depression, and a score over 20 is suggestive of severe depression. The maximum number of points that can be scored is 30.
Gallo, Joseph J., M.D., M.P.H., William Reichel, M.D., and Lillian M. Andersen, R.N., Ed.D. Handbook of Geriatric Assessment.2nd edition. Gaithersburg, MD: Aspen Publishers, Inc., 1995.
Sadavoy, Joel, M.D., F.R.C.P.C., Lawrence W. Lazarus, M.D., Lissy F. Jarvik, M.D., Ph.D., and George T. Grossberg, M.D. eds. Comprehensive Review of Geriatric Psychiatry-II.Washington, DC: American Psychiatric Press, Inc., 1997.
PERIODICALS
Reynolds, Charles F. III, M.D. and David J. Kupfer, M.D. "Depression and Aging: A Look to the Future." Psychiatric Services50 (September 1999): 1167-1172.
Yesavage J. A., T. L. Brink, T. L. Rose, O. Lum, V. Huang, M. Adey and V. O. Leirer. "Development and Validation of a Geriatric Depression Screening Scale: A Preliminary Report." Journal of Psychiatric Research17, no. 1 (1982-83): 37-49.
ORGANIZATIONS
American Association for Geriatric Psychiatry. 7910 Woodmont Ave., Suite 1050, Bethesda, MD, 20814. (301) 654-7850. <http://www.aagponline.org>.
