This is the first attempt to study the prevalence and clinical characteristics of somatisation (ST) in a representative primary care sample in Spain.

The sample consisted of 1559 consecutive patients attending eight randomly selected health centres in Zaragoza, Spain, examined by two-phase screening. First phase (lay interviewers): Spanish versions of GHQ–28, CAGE questionnaire, substance abuse, Mini-Mental State Examination. Second phase (research clinicians and psychiatrists): Standardised Polyvalent Psychiatric Interview, which permits the reliable coding of Bridges & Goldberg's ST criteria.

The prevalence of somatisers was 9.4% (34.5% of the cases) and most patients (68.7%) were diagnosed in the depression or anxiety DSM–IV categories. The severity was moderate in 40.1 % and 66.6% were chronic (six or more months). No significant demographic differences were found with non-cases. Backache was the most frequent somatic presentation (71.4%).

ST in primary care is a much broader phenomenon than categories such as somatoform disorders reflect. It may be less influenced by sociodemographic factors, but more chronic than previously reported.