However, since anxiety and depression are also very common in persons with confirmed medical illnesses, it remains unproven whether such symptoms are a consequence of the physical impairment or a cause. Somatic symptom disorders are not the result of conscious malingering (fabricating or exaggerating symptoms for secondary motives) or factitious disorders (deliberately producing, feigning, or exaggerating symptoms). Somatic symptom disorder is difficult to diagnose and treat. Some advocates of the diagnosis believe this is because proper diagnosis and treatment requires psychiatrists to work with neurologists on patients with this disorder. History
Somitisation disorder was first described by Paul Briquet in 1859 and was subsequently known as Briquets syndrome. He described patients who had been sickly most of their lives and complained of multiple symptoms from different organ systems. Symptoms persist despite multiple consultations,  hospitalisations and investigations. Definition
Somatic symptom disorders are a group of disorders, all of which fit the definition of physical symptoms similar to those observed in physical disease or injury for which there is no identifiable physical cause. As such, they are a diagnosis of exclusion. Somatic symptoms may be generalized in four major medical categories: neurological, cardiac, pain, and gastrointestinal somatic symptoms. Diagnostic and Statistical Manual of Mental Disorders
Somatic symptom disorders used to be recognized as Somatoform disorders in the Diagnostic and Statistical Manual of Mental Disorders of the American Psychiatric Association.
Misdiagnosis
In the opinion of Allen Frances, chair of the DSM-IV task force, the DSM-5s somatic symptom disorder brings with it a risk of mislabeling a sizable proportion of the population as mentally ill. Millions of people could be mislabeled, with the burden falling disproportionately on women, because they are more likely to be casually dismissed as catastrophizers when presenting with physical symptoms. See also
References
Further reading
Suzanne OSullivan (2017). Is It All in Your Head? : True Stories of Imaginary Illness. Other Press. ISBN 978-1590517956.