"Patient knows best"---detection of common mental disorders in Santiago, Chile: cross sectional study Commentary: Clinical practice is as important as diagnosis

# “Patient knows best”—detection of common mental disorders in Santiago, Chile: cross sectional study {#article-title-2} Depression and anxiety are common in primary care but about half of patients with these disorders are not identified by primary care physicians. 1 2 Mental disorder is more likely to be diagnosed in patients who present with or attribute physical symptoms to psychological causes.2–4 We investigated how patients' ways of understanding their health problems influenced the detection of common mental disorder by primary care physicians in Santiago, Chile. We studied 815 consecutive patients seen by 11 primary care physicians from five randomly selected clinics in northern Santiago, Chile. Patients with a chronic illness or patients aged over 50 were excluded because these patients are better known by doctors. Most doctors in Chile and in this study have less than four years' experience in primary care. Before the patient saw the doctor, a lay interviewer asked the patient's reason for consultation and whether it was because of a physical or psychological problem. The interviewer inquired about other potential confounders: physical illness, disability, common somatic symptoms, and whether patients tended to interpret common somatic symptoms by using psychological, physical, or normalising explanations. A psychiatrist administered the clinical interview schedule—revised, and patients scoring 12 or more were classified as having a common mental disorder.5 After the patient had seen the primary care physician, the doctor rated blindly whether the patient had a mental disorder using a five-point scale. Patients with a rating of “mild or greater” severity were considered to have a mental disorder. The prevalence of mental disorders was 49% (396 of 802; 95% confidence interval 46% to 53%) according to the clinical interview schedule—revised and 35% …