Screening for perinatal common mental disorders in women in the north of Vietnam: a comparison of three psychometric instruments.

BACKGROUND: There is increasing recognition that Perinatal Common Mental Disorders (CMDs) are a major public health problem for women in resource-constrained countries. There is an urgent need for screening tools suitable for use by community based health workers to assist in the identification of people with compromised mental health. The aim of this study was to establish the validity of three widely used psychometric screening instruments in detecting CMDs in women in northern Viet Nam.
METHODS: Translated and culturally verified versions of the Edinburgh Postnatal Depression Scale (EPDS), General Health Questionnaire 12 items (GHQ-12), Zung's Self-rated Anxiety Scale (Zung SAS) and a gold-standard diagnostic tool, the Structured Clinical Interview for DSM IV, were administered to a community-based representative cohort of 364 Vietnamese women in the perinatal period. Post-hoc analyses, Cronbach's alpha, and Receiver Operating Characteristic (ROC) analyses were performed to identify the optimal cut-off points and to compare the validity of three scales.
RESULTS: The Areas under the ROC Curve were: EPDS 0.77 (95%CI 0.72-0.82); Zung SAS 0.79 (95%CI 0.74-0.84) and GHQ-12 0.72 (95%CI 0.67-0.78). The optimal cut-off point for the EPDS was 3/4 (Se 69.7%; Sp 72.9%). The corresponding value for Zung SAS was 37/38 (Se 67.9%; Sp 75.3%) and for GHQ-12 was 0/1 (Se 77.1%; Sp 56.6%). The internal reliability Cronbach's alpha for EPDS was 0.75, for Zung SAS was 0.76, and for GHQ-12 was 0.64.
CONCLUSIONS: These instruments are suitable for use as screening tools for CMDs in women in northern Viet Nam, but probably because of differences in emotional literacy, familiarity with test-taking and the effects of chronic social adversity require much lower cut off scores to detect clinically significant symptoms than in other settings.