Perceptualand Motor Skills, 1991, 72, 875.880
O Perceptual and Motor Skills 1991
T H E GERIATRIC DEPRESSION SCALE A N D HOPELESSNESS INDEX: LONGITUDINAL PSYCHOMETRIC DATA O N FRAIL NURSING H O M E RESIDENTS ' IVO L. ABRAHAM Uniuersily of Virginia Summary.-We administered the Geriatric Depression Scale and the Hopelessness Index 18 times over a 39-wk. period to an initial sample of 76 old, frail, multiply impaired, and depressed nursing home residents participating in a longitudinal quasiexperimental study on the effects of cognitive group interventions on cognition, depression, hopelessness, and life satisfaction. As no changes over time were observed on the outcome variables of geriatric depression and hopelessness, the stability of the instruments' internal consistency was examined longitudinally. For the Geriatric Depression Scale, Kuder-Richardson KR-20 coefficients ranged from .69 to .88, with a mean of .82 (SD = .05). Coefficients for the Hopelessness Index were between .72 and .86, with a mean of .80 (SD = .04). We conclude that both instruments give reliable measurements of geriatric depression and hopelessness in old, frail, and depressed nursing home residents
There is increasing interest in understanding the clinical presentation of depression in older adults (Billig, 1987; Blazer, 1982) and investigating clinical interventions to alleviate depressive symptomatology in this population. Most attention has been focused on community-dwelling elderly, who tend to be healthier, more functional, and less cognitively impaired than older adults residing in nursing homes. However, with 10.5% of nursing home residents suffering from diagnostically classifiable forms of depression and an additional 16.5% exhibiting depressive symptomatology (Parmelee, Katz, & Lawton, 1989), there has been heightened interest in measuring the outcomes of clinical interventions for this population. Longitudinal studies, in particular, are being recognized as critical avenues for understanding and managing geriatric depression and some of its psychoemotional correlates among institutionalized older adults. A consistent problem has been the limited psychometric support for instruments commonly employed with community-dwelling elderly in research involving nursing home residents. I n this article, we report on the internal consistency reliability of the Geriatric Depression Scale (Yesavage, Brink, Rose, Lum, Huang, Adey, & Leirer, 1983) and the Hopelessness Index (Beck, Weissman, Lester, & Trexler, 1974) over 18 repeated adrninis-
'Supported by Grants lROlNR01566 from the National Center for Nursing Research, National Institutes of Health, and lTOlMH19362 from the National Institute of Mental Health. The author thanks anonymous referees for their helpful sug estions. Address correspondence to the author, University of Virginia, Madison House, 170 R U ~ %Road, ~ Charlottesville, VA 22903.
876
I. L. ABRAHAM
trations in a quasi-experimental study involving frail, multiply impaired nursing home residents. This study investigated the effects of cognitivebehavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups (the latter serving as an "attention" comparison condition) on cognition, depression, hopelessness, and life satisfaction; see Abraham, Niles, Thiel, Siarkowski, and Cowling (in press) for a review of clinical protocols and Abraham (1989) and Abraham, Neundorfer, and Currie (1991) for a description of methods and a summary of findings. Since no significant changes were observed on the outcome variables of geriatric depression and hopelessness across and within subsamples, a longitudinal investigation of the stability of the instruments' internal consistency is appropriate as experimental effects can be excluded as a source of variation.
METHOD The description of methods is limited to the present focus on the longitudinal internal consistency of the Geriatric Depression Scale and the HopeIessness Index. For complete details on the study, including measures of central tendency and dispersion as well as statistical analyses, see Abraham (1989) and Abraham, et al. (1991). Sample The sample consisted of 76 older adults residing in seven nursing homes, who met a set of sampling criteria defining necessary characteristics for admission to the study and ability to participate in group sessions (see Abraham [I9891 for details of assessment and verification): (1) a score of 11 or higher on the Geriatric Depression Scale (Yesavage, et al., 1983), or a score of 10 with demonstrable clinical evidence of depression, (2) sufficient hearing, (3) adequate vision, (4) adequate verbal and comprehension slulls, (5) absence of major cognitive impairment, (6) not taking any antidepressant medication, and (7) no history of endogenous depression. Subjects meeting these criteria had to be recruited from seven nursing homes (894 beds total). Seventeen subjects were men (22.4%) and 59 were women (77.6%), which corresponds to the gender mix typically seen in long-term care facilities. Table 1 summarizes the demographic characteristics of the subjects; cognitive status was measured by means of the Modified Mini-Mental State (Teng & Chui, 1987), which ranges from 0 to 100, with a dementia cut-off of 80. From this table it can be concluded that the sample constituted a group of frail elderly, of advanced age, including cognitively intact as well as cognitively impaired people, who had been institutionalized for quite some time, who were physically quite ill, and exhibited mild, moderate, or severe depression.
Instruments Geriatric Depression Scale.-This
instrument was developed by Yesavage,
877
DEPRESSION, HOPELESSNESS AMONG ELDERLY
et al. (1983) because few of the existing depression scales for adults had been validated for use with elderly persons. The scale consists of 30 items to be scored in a yeslno format. These items were developed by clinicians and researchers, and the initial set of 100 items was reduced to 30 by means of item and related psychometric analyses. Yesavage, et al. (1983) obtained compelling psychometric indicators, and the scale has become an accepted measure of depression in late life (Allen & Blazer, 1991). A study of 100 elderly subjects, of whom 40 had no history of mental illness and 60 were patients in treatment for depression, yielded an internal consistency coefficient of .94. A test-retest coefficient of .94 was obtained from a subsample of 20 subjects (Yesavage, et al., 1983). The scale differentiates accurately between nondepressed, -&Idly depressed, and severely depressed older adults. The Geriatric Depression Scale is scored by summation of "yes" answers after inversion for oppositely stated items. A high score indicates high depression. On the basis of scores, subjects can be classified as severely depressed (21-30), mildly depressed (11-20), or normal (0-10). TABLE 1 DEMOGRAPHIC CHARACTERIST~CS OF SUBJECTS ( N = 76) Range Age (in years) Depression Cognitive Status Length of Stay in Nursing Home (in months) Total Diagnoses Total Medications
71-97 10-28 33-97 1-92 1-14 0-13
M
SD
84.38 17.93 75.83 40.30 5.50 6.22
6.13 4.16 13.05 43.94 2.38 2.33
Hopelessness Index.-This instrument, developed by Beck, Weissman, Lester, and Trexler (1974), is a 20-item truelfalse scale measuring hopelessness as the perceptual experience of anticipation of undesirable situations or consequences that are largely beyond one's control. Beck, et al. (1974) reported an internal consistency estimate of .93, with item-total correlations ranging from .39 to .76. Concurrent criterion-related vahdity was established in two independent studies in which scores were compared to clinical ratings, yielding correlation coefficients of .74 and .62. The Hopelessness Index also correlated significantly with the Stuart Future Test ( r = .60) and the pessimism item of the Beck Depression Inventory ( r = .63). The Hopelessness Index is scored through summation. The higher the score, the more pronounced the hopelessness. Design The data reported in this paper were obtained in a quasi-experimental study (Abraham, 1989) designed as an interrupted time series with three
878
I. L. ABRAHAM
removed treatments: cognitive-behavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups; see Abraham, et al. (in press) for a description of clinical protocols. The design consisted of a 4-wk. pretreatment period (two data collections at 2-wk. intervals), a 24-wk. treatment period (13 data collections at 2-wk. intervals), and an 8-wk. posttreatment period (three data collections at 2, 4, and 8 wk. following completion of the interventions).
Procedure Four trained interviewers were randomly assigned to the seven nursing homes and collected data according to a preestablished calender. Interviewers were blind to the treatment condition to which the subject was assigned.
RESULTS Table 2 presents the KR-20 estimates for the Geriatric Depression Scale and the Hopelessness Index at each of the 18 time points. For the former, coefficients ranged from .69 to .88. Fifteen coefficients (83.3%) fell in the .81 to .90 range, two in the .71 to .80 (11.1%) range, and one in the .61 to .70 (5.6%) range. The mean coefficient across the 18 time points was .82 (SD = .05). For the Hopelessness Index, coefficients ranged from .72 to .86. Eight coefficients (44.4%) fell in the .71 to .80 range and ten in the .81 to .90 range (55.6%). The mean coefficient across the 18 time points was .80 (SD = .04). TABLE 2 ESTIMATES OF INTERNAL CONSISTENCY (KR-20)OF GERIATRIC DEPRESSION SCALE AND HOPELESSNESS INDEXAT EACHTIMEPOINT Time Point
Geriatric Depression Scale
Hopelessness Index
DEPRESSION, HOPELESSNESS AMONG ELDERLY
879
The Geriatric Depression Scale and the Hopelessness Index were used with nursing home residents as part of a study comparing the effectiveness of three cognitive group interventions (cognitive-behavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups) on cognition, depression, hopelessness, and life satisfaction. Since these interventions had no effect on subjects' depression and hopelessness (Abraham, 1989; Abraham, et al., 1991), it was appropriate to pool data across treatment conditions and examine the internal consistency reliability over the 18 time points featured in the study. Both the Geriatric Depression Scale and rhe Hopelessness Index were reliable instruments for measuring geriatric depression and hopelessness in depressed elderly persons living in long-term care facilities. Internal consistency estimates were high across the 18 time points and attest to the longitudinal measurement reliability of these scales. While the findings reported here were not obtained in a psychometric investigation per se, the consistency of the high reliability estimates should not go unrecognized. Yet it is also important to consider alternative explanations for the obtained results. First, the absence of a noticeable longitudinal effect of any of the interventions on depression and hopelessness may represent low statistical power. However, as we documented elsewhere (Abraham, 1989; Abraham, et al., 1991), following Kirk's (1982) computations our residual sample size satisfied the requirements for detecting differences of 1.5 standardized units, with a power of .90 (a = .05). Second, both the Geriatric Depression Scale and the Hopelessness Index may have been insufficiently sensitive. This is a possibility, yet these instruments are well-accepted measures with convincing psychometric properties. Third, the high internal consistency coefficients obtained over time might reflect repeated testing. The first 15 data collections were done at 2-wk. intervals and the final three at 3-wk. intervals in an attempt to strike a balance between avoiding testing effects and being able to examine the course of change (if any) over time. I t would have been interesting to report analyses separately for cognitively impaired and intact subjects. However, given the size of the present sample, this would have led to two small subsamples and the consequent risk of obtaining perhaps significant but likely unstable coefficients. Separate analyses are necessary in the future and should be integrated into the psychometric investigations that must be conducted to validate more rigorously the findings reported here. Longitudinal, psychometric studies should be designed such that the stability of the two instruments over time can be assessed by such means as pairwise correlations for each subject over the times tested and the computation of intraclass correlation coefficients. However, until specific psychometric investigations are conducted, our data pro-
880
I. L. ABRAHAM
vide compelling evidence for the internal consistency reliability of the Geriatric Depression Scale and the Hopelessness Index in longitudinal research involving old, frail, and multiply impaired nursing home residents. REFERENCES ABRAHAM, I. L. (1989) Comparative effectiveness of group interventions for depressed elderly in long term care. Final Report of Grant lROlNR1566, National Center for Nursing Research, National Institutes of Health, Bethesda, MD. ABRAHAM,I. L., NEUNDORFEK, M. M., & CLIRRTE, L. J. (1991) Comparative effectiveness of cognitive group interventions on cognition and depression among frail nursing home residents. Manuscript submitted for publication. ABRAHAM, I. L., NILES, S. A., THIEL,B. l?, SIARKOWSKI, K. I., & COWLING, W. R. (in press) Therapeutic group work with depressed elderly. Nursing Clinics of North America. ALLEN,A,, & BLAZER,D. G. (1991) Mood disorders. In J. Sadavoy, L. W. Lazarus, & L. F. Jarvik (Eds.), Comprehensive review of geriatric psychiatry. Washington, DC: American Psychiatric Press. Pp. 337-352. BECK,A. T., WEISSMAN,A,, LESTER,D., & TREXLER, L. (1974) The measurement of pessimism: the Hopelessness Scale. Journal of Consulting and Clinical Psychology, 55, 550556. BULIG, N. (1987) To be OM and sad: understanding depression in the elderly. Lexington, M A : Heath. BLAZER,D. G. (1982) Depression in late life. St. Louis, MO: Mosby. KIRK, R. E. (1982) Experimental design. (2nd ed.) Monterey, CA: Wadsworth. l? A,, KATZ, I. R., & LAWTON,M. P. (1989) Depression among institutionalized PARMELEE, aged: assessment and prevalence estimation. Journal of Gerontology: Medical Sciences, 44, M22-M29. TENG,E. L., & CHUI, H . C. (1987) The Modified Mini-Mental State (3MS) Examination. Journal of Clinical Psychiatry, 48, 3 14-317. YESAVAGE, J. A,, BRINK,T. L., ROSE,T. L., LUM, O., HUANG,V., ADEY,M., & LEIRER,V. 0. (1983) Development and validation of a geriatric depression screening scale: a preliminary report. Jozirnal of Psychiatric Research, 17, 37-49.
Accepted April 23, 1991
O Perceptual and Motor Skills 1991
T H E GERIATRIC DEPRESSION SCALE A N D HOPELESSNESS INDEX: LONGITUDINAL PSYCHOMETRIC DATA O N FRAIL NURSING H O M E RESIDENTS ' IVO L. ABRAHAM Uniuersily of Virginia Summary.-We administered the Geriatric Depression Scale and the Hopelessness Index 18 times over a 39-wk. period to an initial sample of 76 old, frail, multiply impaired, and depressed nursing home residents participating in a longitudinal quasiexperimental study on the effects of cognitive group interventions on cognition, depression, hopelessness, and life satisfaction. As no changes over time were observed on the outcome variables of geriatric depression and hopelessness, the stability of the instruments' internal consistency was examined longitudinally. For the Geriatric Depression Scale, Kuder-Richardson KR-20 coefficients ranged from .69 to .88, with a mean of .82 (SD = .05). Coefficients for the Hopelessness Index were between .72 and .86, with a mean of .80 (SD = .04). We conclude that both instruments give reliable measurements of geriatric depression and hopelessness in old, frail, and depressed nursing home residents
There is increasing interest in understanding the clinical presentation of depression in older adults (Billig, 1987; Blazer, 1982) and investigating clinical interventions to alleviate depressive symptomatology in this population. Most attention has been focused on community-dwelling elderly, who tend to be healthier, more functional, and less cognitively impaired than older adults residing in nursing homes. However, with 10.5% of nursing home residents suffering from diagnostically classifiable forms of depression and an additional 16.5% exhibiting depressive symptomatology (Parmelee, Katz, & Lawton, 1989), there has been heightened interest in measuring the outcomes of clinical interventions for this population. Longitudinal studies, in particular, are being recognized as critical avenues for understanding and managing geriatric depression and some of its psychoemotional correlates among institutionalized older adults. A consistent problem has been the limited psychometric support for instruments commonly employed with community-dwelling elderly in research involving nursing home residents. I n this article, we report on the internal consistency reliability of the Geriatric Depression Scale (Yesavage, Brink, Rose, Lum, Huang, Adey, & Leirer, 1983) and the Hopelessness Index (Beck, Weissman, Lester, & Trexler, 1974) over 18 repeated adrninis-
'Supported by Grants lROlNR01566 from the National Center for Nursing Research, National Institutes of Health, and lTOlMH19362 from the National Institute of Mental Health. The author thanks anonymous referees for their helpful sug estions. Address correspondence to the author, University of Virginia, Madison House, 170 R U ~ %Road, ~ Charlottesville, VA 22903.
876
I. L. ABRAHAM
trations in a quasi-experimental study involving frail, multiply impaired nursing home residents. This study investigated the effects of cognitivebehavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups (the latter serving as an "attention" comparison condition) on cognition, depression, hopelessness, and life satisfaction; see Abraham, Niles, Thiel, Siarkowski, and Cowling (in press) for a review of clinical protocols and Abraham (1989) and Abraham, Neundorfer, and Currie (1991) for a description of methods and a summary of findings. Since no significant changes were observed on the outcome variables of geriatric depression and hopelessness across and within subsamples, a longitudinal investigation of the stability of the instruments' internal consistency is appropriate as experimental effects can be excluded as a source of variation.
METHOD The description of methods is limited to the present focus on the longitudinal internal consistency of the Geriatric Depression Scale and the HopeIessness Index. For complete details on the study, including measures of central tendency and dispersion as well as statistical analyses, see Abraham (1989) and Abraham, et al. (1991). Sample The sample consisted of 76 older adults residing in seven nursing homes, who met a set of sampling criteria defining necessary characteristics for admission to the study and ability to participate in group sessions (see Abraham [I9891 for details of assessment and verification): (1) a score of 11 or higher on the Geriatric Depression Scale (Yesavage, et al., 1983), or a score of 10 with demonstrable clinical evidence of depression, (2) sufficient hearing, (3) adequate vision, (4) adequate verbal and comprehension slulls, (5) absence of major cognitive impairment, (6) not taking any antidepressant medication, and (7) no history of endogenous depression. Subjects meeting these criteria had to be recruited from seven nursing homes (894 beds total). Seventeen subjects were men (22.4%) and 59 were women (77.6%), which corresponds to the gender mix typically seen in long-term care facilities. Table 1 summarizes the demographic characteristics of the subjects; cognitive status was measured by means of the Modified Mini-Mental State (Teng & Chui, 1987), which ranges from 0 to 100, with a dementia cut-off of 80. From this table it can be concluded that the sample constituted a group of frail elderly, of advanced age, including cognitively intact as well as cognitively impaired people, who had been institutionalized for quite some time, who were physically quite ill, and exhibited mild, moderate, or severe depression.
Instruments Geriatric Depression Scale.-This
instrument was developed by Yesavage,
877
DEPRESSION, HOPELESSNESS AMONG ELDERLY
et al. (1983) because few of the existing depression scales for adults had been validated for use with elderly persons. The scale consists of 30 items to be scored in a yeslno format. These items were developed by clinicians and researchers, and the initial set of 100 items was reduced to 30 by means of item and related psychometric analyses. Yesavage, et al. (1983) obtained compelling psychometric indicators, and the scale has become an accepted measure of depression in late life (Allen & Blazer, 1991). A study of 100 elderly subjects, of whom 40 had no history of mental illness and 60 were patients in treatment for depression, yielded an internal consistency coefficient of .94. A test-retest coefficient of .94 was obtained from a subsample of 20 subjects (Yesavage, et al., 1983). The scale differentiates accurately between nondepressed, -&Idly depressed, and severely depressed older adults. The Geriatric Depression Scale is scored by summation of "yes" answers after inversion for oppositely stated items. A high score indicates high depression. On the basis of scores, subjects can be classified as severely depressed (21-30), mildly depressed (11-20), or normal (0-10). TABLE 1 DEMOGRAPHIC CHARACTERIST~CS OF SUBJECTS ( N = 76) Range Age (in years) Depression Cognitive Status Length of Stay in Nursing Home (in months) Total Diagnoses Total Medications
71-97 10-28 33-97 1-92 1-14 0-13
M
SD
84.38 17.93 75.83 40.30 5.50 6.22
6.13 4.16 13.05 43.94 2.38 2.33
Hopelessness Index.-This instrument, developed by Beck, Weissman, Lester, and Trexler (1974), is a 20-item truelfalse scale measuring hopelessness as the perceptual experience of anticipation of undesirable situations or consequences that are largely beyond one's control. Beck, et al. (1974) reported an internal consistency estimate of .93, with item-total correlations ranging from .39 to .76. Concurrent criterion-related vahdity was established in two independent studies in which scores were compared to clinical ratings, yielding correlation coefficients of .74 and .62. The Hopelessness Index also correlated significantly with the Stuart Future Test ( r = .60) and the pessimism item of the Beck Depression Inventory ( r = .63). The Hopelessness Index is scored through summation. The higher the score, the more pronounced the hopelessness. Design The data reported in this paper were obtained in a quasi-experimental study (Abraham, 1989) designed as an interrupted time series with three
878
I. L. ABRAHAM
removed treatments: cognitive-behavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups; see Abraham, et al. (in press) for a description of clinical protocols. The design consisted of a 4-wk. pretreatment period (two data collections at 2-wk. intervals), a 24-wk. treatment period (13 data collections at 2-wk. intervals), and an 8-wk. posttreatment period (three data collections at 2, 4, and 8 wk. following completion of the interventions).
Procedure Four trained interviewers were randomly assigned to the seven nursing homes and collected data according to a preestablished calender. Interviewers were blind to the treatment condition to which the subject was assigned.
RESULTS Table 2 presents the KR-20 estimates for the Geriatric Depression Scale and the Hopelessness Index at each of the 18 time points. For the former, coefficients ranged from .69 to .88. Fifteen coefficients (83.3%) fell in the .81 to .90 range, two in the .71 to .80 (11.1%) range, and one in the .61 to .70 (5.6%) range. The mean coefficient across the 18 time points was .82 (SD = .05). For the Hopelessness Index, coefficients ranged from .72 to .86. Eight coefficients (44.4%) fell in the .71 to .80 range and ten in the .81 to .90 range (55.6%). The mean coefficient across the 18 time points was .80 (SD = .04). TABLE 2 ESTIMATES OF INTERNAL CONSISTENCY (KR-20)OF GERIATRIC DEPRESSION SCALE AND HOPELESSNESS INDEXAT EACHTIMEPOINT Time Point
Geriatric Depression Scale
Hopelessness Index
DEPRESSION, HOPELESSNESS AMONG ELDERLY
879
The Geriatric Depression Scale and the Hopelessness Index were used with nursing home residents as part of a study comparing the effectiveness of three cognitive group interventions (cognitive-behavioral group therapy, focused visual-imagery in group therapy, and educational discussion groups) on cognition, depression, hopelessness, and life satisfaction. Since these interventions had no effect on subjects' depression and hopelessness (Abraham, 1989; Abraham, et al., 1991), it was appropriate to pool data across treatment conditions and examine the internal consistency reliability over the 18 time points featured in the study. Both the Geriatric Depression Scale and rhe Hopelessness Index were reliable instruments for measuring geriatric depression and hopelessness in depressed elderly persons living in long-term care facilities. Internal consistency estimates were high across the 18 time points and attest to the longitudinal measurement reliability of these scales. While the findings reported here were not obtained in a psychometric investigation per se, the consistency of the high reliability estimates should not go unrecognized. Yet it is also important to consider alternative explanations for the obtained results. First, the absence of a noticeable longitudinal effect of any of the interventions on depression and hopelessness may represent low statistical power. However, as we documented elsewhere (Abraham, 1989; Abraham, et al., 1991), following Kirk's (1982) computations our residual sample size satisfied the requirements for detecting differences of 1.5 standardized units, with a power of .90 (a = .05). Second, both the Geriatric Depression Scale and the Hopelessness Index may have been insufficiently sensitive. This is a possibility, yet these instruments are well-accepted measures with convincing psychometric properties. Third, the high internal consistency coefficients obtained over time might reflect repeated testing. The first 15 data collections were done at 2-wk. intervals and the final three at 3-wk. intervals in an attempt to strike a balance between avoiding testing effects and being able to examine the course of change (if any) over time. I t would have been interesting to report analyses separately for cognitively impaired and intact subjects. However, given the size of the present sample, this would have led to two small subsamples and the consequent risk of obtaining perhaps significant but likely unstable coefficients. Separate analyses are necessary in the future and should be integrated into the psychometric investigations that must be conducted to validate more rigorously the findings reported here. Longitudinal, psychometric studies should be designed such that the stability of the two instruments over time can be assessed by such means as pairwise correlations for each subject over the times tested and the computation of intraclass correlation coefficients. However, until specific psychometric investigations are conducted, our data pro-
880
I. L. ABRAHAM
vide compelling evidence for the internal consistency reliability of the Geriatric Depression Scale and the Hopelessness Index in longitudinal research involving old, frail, and multiply impaired nursing home residents. REFERENCES ABRAHAM, I. L. (1989) Comparative effectiveness of group interventions for depressed elderly in long term care. Final Report of Grant lROlNR1566, National Center for Nursing Research, National Institutes of Health, Bethesda, MD. ABRAHAM,I. L., NEUNDORFEK, M. M., & CLIRRTE, L. J. (1991) Comparative effectiveness of cognitive group interventions on cognition and depression among frail nursing home residents. Manuscript submitted for publication. ABRAHAM, I. L., NILES, S. A., THIEL,B. l?, SIARKOWSKI, K. I., & COWLING, W. R. (in press) Therapeutic group work with depressed elderly. Nursing Clinics of North America. ALLEN,A,, & BLAZER,D. G. (1991) Mood disorders. In J. Sadavoy, L. W. Lazarus, & L. F. Jarvik (Eds.), Comprehensive review of geriatric psychiatry. Washington, DC: American Psychiatric Press. Pp. 337-352. BECK,A. T., WEISSMAN,A,, LESTER,D., & TREXLER, L. (1974) The measurement of pessimism: the Hopelessness Scale. Journal of Consulting and Clinical Psychology, 55, 550556. BULIG, N. (1987) To be OM and sad: understanding depression in the elderly. Lexington, M A : Heath. BLAZER,D. G. (1982) Depression in late life. St. Louis, MO: Mosby. KIRK, R. E. (1982) Experimental design. (2nd ed.) Monterey, CA: Wadsworth. l? A,, KATZ, I. R., & LAWTON,M. P. (1989) Depression among institutionalized PARMELEE, aged: assessment and prevalence estimation. Journal of Gerontology: Medical Sciences, 44, M22-M29. TENG,E. L., & CHUI, H . C. (1987) The Modified Mini-Mental State (3MS) Examination. Journal of Clinical Psychiatry, 48, 3 14-317. YESAVAGE, J. A,, BRINK,T. L., ROSE,T. L., LUM, O., HUANG,V., ADEY,M., & LEIRER,V. 0. (1983) Development and validation of a geriatric depression screening scale: a preliminary report. Jozirnal of Psychiatric Research, 17, 37-49.
Accepted April 23, 1991
