Structural factor analyses for medically unexplained somatic symptoms of somatization disorder in the Epidemiologic Catchment Area study

Psychol Med. 1997 May;27(3):617-26. doi: 10.1017/s0033291797004844.


Background: Assess the latent structure of the DSM-III somatization symptoms and the stability of symptom patterns over time.

Methods: Cross-sectional and longitudinal covariation of symptoms of somatization disorder were investigated using structural equation models in a population-based data set from the Epidemiologic Catchment Area study.

Results: Medically unexplained physical complaints were discovered to cluster into three separate factors, consistent with the DSM-IV definition of somatization disorder, but one dominant general factor was defined, consistent with the DSM-III conceptualization. Individual symptom prevalences and factor structures were different for men and women. The factor structures remained stable at 1 year follow-up. Variations in the threshold of number of somatization symptoms required for diagnosis affected prevalence, sex ratio and temporal stability of the diagnosis.

Conclusions: These population-based results support dimensional models of somatization. Implications for changing the threshold of the categorical diagnosis of somatization disorder and providing better care for these patients are given.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Chronic Disease
  • Conversion Disorder / epidemiology
  • Cross-Sectional Studies
  • Factor Analysis, Statistical
  • Female
  • Health Surveys
  • Humans
  • Least-Squares Analysis
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Models, Psychological
  • Odds Ratio
  • Pain / epidemiology
  • Pain / psychology
  • Prevalence
  • Reference Values
  • Sex Distribution
  • Somatoform Disorders / diagnosis
  • Somatoform Disorders / epidemiology*
  • Somatoform Disorders / physiopathology
  • United States / epidemiology