Objective: To review the evidence from randomized clinical trials (RCTs) that have focused on the treatment of patients with
Diagnostic and Statistical Manual of Mental Disorders, 4th
Edition (DSM-IV) somatoform disorders. Although somatoform
disorders are among the most common mental disorders presenting in the general medical setting, the strength of evidence for
specific treatments has not been well synthesized. Methods: MEDLINE search of articles published in English from 1966 to 2006,
using the following search terms: randomized clinical trial, somatoform disorders, somatization disorder, undifferentiated somato-
form disorder, hypochrondriasis, conversion disorder, pain disorder, and body dysmorphic disorder. Results: A total of 34 RCTs
involving 3922 patients were included. Two thirds of the studies involved somatization disorder (n 4 studies) and lower threshold
variants, such as abridged somatization disorder (n 9) and medically unexplained symptoms (n 10). Cognitive behavioral
therapy (CBT) was effective in most studies (11 of 13), as were antidepressants in a small number (4 of 5) of studies. RCTs
examining a variety of other treatments showed benefit in half (8 of 16) of the studies, the most consistent evidence existing for
a consultation letter to the primary care physician. Effective treatments have been established for all somatoform disorders except
conversion disorder (1 of 3 studies showing benefit) and pain disorder (no studies reported). Conclusion: CBT is the best
established treatment for a variety of somatoform disorders, with some benefit also demonstrated for a consultation letter to the
primary care physician. Preliminary but not yet conclusive evidence exists for antidepressants. Key words: somatoform disorders,
somatization, therapy, randomized controlled trials, review.