The cross-national structure of mental disorders: results from the World Mental Health Surveys

Abstract

Background The patterns of comorbidity among mental disorders have led researchers to model the underlying structure of psychopathology. While studies have suggested a structure including internalizing and externalizing disorders, less is known with regard to the cross-national stability of this model. Moreover, little data is available on the placement of eating disorders, bipolar disorder and psychotic experiences in this structure.

Methods We evaluated the structure of mental disorders with data from the World Health Organization Composite International Diagnostic Interview, including 15 lifetime mental disorders and six psychotic experiences. Respondents (n=5,478–15,499) were included from 10 high, middle and lower-middle income countries across the world aged 18 years or older. Confirmatory Factor Analyses (CFA) were used to evaluate and compare the fit of different factor structures to the lifetime disorder data. measurement invariance was evaluated with multigroup CFA (MG-CFA).

Results A second-order model with internalizing and externalizing factors and fear and distress subfactors best described the structure of common mental disorders. MG-CFA showed that this model was stable across countries. Of the uncommon disorders, bipolar disorder and eating disorder were best grouped with the internalizing factor, and psychotic experiences with a separate factor.

Conclusions These results indicate that cross-national patterns of lifetime common mental-disorder comorbidity can be explained with a second-order underlying structure that is stable across countries and can be extended to also cover less common mental disorders.