Dimensional latent structure of somatic symptom reporting in two representative population studies: results from taxometric analyses.

Somatoform disorders are characterized by somatic symptoms that suggest a medical condition when such a condition is not present. Recently, Thomas and Locke (2010) and Jasper, Hiller, Rist, Bailer, and Witthöft (2012) found that the latent status of somatic symptom reporting may be best viewed from a dimensional perspective in a student, primary care, and an epilepsy-monitoring-unit setting using the Minnesota Multiphasic Personality Inventory-2-Restructured Form Somatic Complaints (RC1) Scale and Patient Health Questionnaire (PHQ-15). To determine whether the latent status of somatic symptom reporting is dimensional in general population samples and across other measures, we analyzed the latent status of somatic symptom reporting in 2 large general German population samples using the PHQ-15 and Screening for Somatoform Symptoms (SOMS-7; N1 = 2,469; N2 = 2,434). We applied 3 popular taxometric methods: MAXEIG, MAMBAC, and L-Mode. In both samples, the analyses indicated a dimensional solution. Hence, the latent structure of somatic symptom reporting encompasses differences in degree rather than kind. Implications of the dimensional latent status of somatoform disorders regarding assessment and causality are discussed.