A study of 2,300 individuals by researchers at Rhode Island Hospital, U.S. used standardized interviews to evaluate a wide range of psychiatric disorders in a general, clinical outpatient practice. The researchers found that a majority of the patients had more than one mental-health problem and a third of them had at least three. Depression was the most common diagnosis, followed by social phobia. On average patients had 1.9 diagnoses. Patients with principal diagnoses of post-traumatic stress disorder (PTSD) and bipolar disorder had the most concurrent diagnoses. Major depression was the most common reason for seeking treatment, however, while social phobia was the second most common diagnosis in the study 95% of the people suffering from it came for treatment for another mental-health problem.
You can find out more about this research at