Factor structure of the Chinese version of the 12-item General Health Questionnaire (GHQ-12) in pregnancy

The GHQ-12 is a widely used instrument designed to detect psychological disturbance in a wide variety of clinical groups. The Chinese version of the GHQ-12 is widely used in Hong Kong to screen women during pregnancy and in the postnatal period. Recent evaluations of this instrument in pregnancy and in the postnatal period have suggested the instrument may be unsultable for screening for psychological distress in this clinical group due to differences in case detection rates as a function of alternative scoring methods. However, a more fundamental issue regarding this instrument concerns reported inconsistencies and ambiguities in the factor structure of the instrument. The current investigation explored the underlying factor structure of this instrument using exploratory factor analysis and confirmatory factor analysis in Chinese women during the third trimester of pregnancy. The GHQ-12 was found to be internally consistent; however, two- and three-factor models offered superior fit to the data compared to the presumed uni-dimensional structure. The claim that the GHQ-12 is a uni-dimensional measure of psychological distress was not supported Further research is necessary to determine if the underlying multi-dimensional factor structure of the GHQ-12 in pregnancy may impact on case detection accuracy and instrument validity.