Validation of the Patient Health Questionnaire-9 Korean version in the elderly population: the Ansan Geriatric study.
OBJECTIVE
We evaluated the diagnostic validity of the 9-item depression module of the Patient Health Questionnaire-9 (PHQ-9) in elderly Korean patients and suggest an optimal cutoff score to screen for major depressive disorders.


METHODS
The PHQ-9 and an elderly health questionnaire were administered to 1060 subjects older than 60 years, chosen using a stratified random sample of the community. The PHQ-9 was measured and compared with the Geriatric Depression Scale, Center for Epidemiological Studies Depression Scale, and Beck Depression Inventory scores. Reliability and validity tests, factor analysis, and receiver operating characteristic curve analysis were performed.


RESULTS
The PHQ-9 indicated that 175 subjects had depressive disorders, and 885 subjects were rated as healthy. The PHQ-9 showed significant positive internal consistency (r = 0.88) and test-retest reliability (r = 0.60). The convergent validity with Geriatric Depression Scale and Center for Epidemiological Studies Depression Scale was significantly positive (r = 0.74 and 0.66, respectively). We suggest a score of 5 as the optimal cutoff point when screening for depressive disorders using the PHQ-9.


CONCLUSIONS
The Korean version of the PHQ-9 is an appropriate diagnostic tool for depression, and a score of 5 is the optimal cutoff for Korean elderly subjects. Screening for depression in the elderly population using the PHQ-9 would be valuable when medically ill patients show depressive symptoms in a primary health care setting.
Han
Changsu
C
Department of Psychiatry, College of Medicine, Korea University, Ansan City, Gyunggi Province 425-707, South Korea.
Jo
Sangmee Ahn
SA
Kwak
Ji-Hyun
JH
Pae
Chi-Un
CU
Steffens
David
D
Jo
Inho
I
Park
Moon Ho
MH
D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000208:ethnology*; D003863:Depression / Q000175:diagnosis* / Q000208:ethnology*; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires