Background: There is a need to develop instruments to measure mental disorders in developing countries because mental disorders are increasingly being recognised as a major public health problem. There has been no previous study in Vietnam validating screening instruments for mental health problems.
Aim: To adapt and to validate the Self Reporting Questionnaire-20 (SRQ-20) in the Vietnamese community.
Methods: A Vietnamese version of the SRQ-20 was developed and tested in 52 persons in a district hospital sample and 485 persons in a community sample. The psychiatrists' diagnoses were taken as the validity criterion. Receiver Operating Characteristic (ROC) analysis was performed to identify the optimal cut-off value. The area under the ROC curve (AUC) was calculated to assess the performance of SRQ in different sociodemographic groups.
Results: In the district hospital sample, the optimal cut-off score was 5/6 with a sensitivity of 85%, a specificity of 46% and an AUC of 0.74 (95% CI: 0.59-0.89). In the community sample, it was 6/7 with a sensitivity of 85%, a specificity of 61% and AUC of 0.86 (95% CI: 0.81-0.93). In terms of AUC, SRQ performed significantly better in the age group 18-24 years as compared with other ages and with single persons as compared with widowed or divorced people.
Conclusion: The SRQ-20 was found feasible to use and adapt to the Vietnamese setting. We confirmed the value of this instrument for use in developing countries, but the optimal cut-off limit has to be assessed and determined according to local conditions.