Somatization is a psychological process leading to the experience of somatic symptoms in response to psychosocial factors. Variations in sampling, nosology and instrumentation have contributed to uncertainty about the prevalence of the diagnosis of somatization disorder(s). We estimated the pooled prevalence of relevant classifications of somatization syndromes in unselected and selected adult primary care populations.
Methods
We searched electronic databases from 1946 to 2022 and selected all papers in adult primary care populations reporting prevalence of any somatization syndrome. A series of random effects meta-analyses calculated pooled estimates of prevalence. Primary outcomes were any somatoform disorder, individual somatization syndrome, and PHQ-15 derived ‘diagnosis’. Secondary outcomes were somatization syndromes by clinician diagnosis, classification system, diagnostic instrument and gender.
Results
In unselected primary care populations the pooled mean prevalence was: Somatoform disorder 16.3%; individual somatization syndrome 7.7%; and PHQ-15 any severity 18.7%. Meta-regressions showed modification by diagnostic instrument but no effect of decade or geographical location. Selected populations generally had higher prevalence estimates for equivalent diagnoses.
Conclusions
Somatization syndromes in primary care are common, affecting more than one in 10 patients. Recent classification systems may represent a substantial widening in conceptualisation of somatization syndromes, especially for somatization disorder and so future studies will be needed to compare prevalence estimates.
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