Assessment of psychological aspects of somatoform disorders: a study on the German version of the Health Attitude Survey (HAS)

Abstract

Objective: Given the prevalence and costs of somatoform disorders, it is important to identify and adequately treat these patients as early as possible. Instruments assessing experiences, perceptions, and behaviors of somatoform disorders are rare. In this study we evaluated the structure and validity of the German version of the Health Attitude Survey (HAS), a multidimensional self-report questionnaire for somatoform disorders.

Methods: This cross-sectional study involved 1452 participants. The sample was randomly split for independent exploratory (EFA) and confirmatory factor analyses (CFA). Each of the two samples (n1=726; n2=726) included patients with organic vertigo and current mental disorders (somatoform and other mental disorders). Somatic symptom burden was assessed using the Patient Health Questionnaire (PHQ-15).

Results: The CFA did not confirm the original HAS factor structure. The EFA revealed six factors. To enhance the fit of the model, we deleted two factors with the poorest reliability and items with low factor loadings. A modified and shortened version achieved good fit indices (CFI=0.92; RMSEA=0.068). It consists of 14 instead of 27 items and four scales ("dissatisfaction with care," "frustration with ill health," "high utilization of care," "excessive health worry"). HAS subscales discriminated among somatoform patients and physically ill and/or patients with a mental but not somatoform disorder, controlled for age, sex and number of (comorbid) mental diagnoses, confirming its construct validity.

Conclusion: A modified shortened version of the HAS appears to be a reliable, valid, and economical instrument for assessing facets of somatoform disorders or of the recently published DSM-5 Somatic Symptom Disorder.