Use of the ICD-10 classification in psychiatry: an international survey

On the background of some years of experience with ICD-10 psychiatric diagnoses in many countries of the world, an international comparison was performed to evaluate the frequency and use of the ICD-10 psychiatric diagnoses. For future revision of the ICD-10, it is important to know which diagnostic categories are either not used or are used possibly in an unspecific manner. Nineteen departments of psychiatry in 10 different countries took part in the study, presenting data on 33,857 treatment cases leading to a total of 25,470 ICD-10 main diagnoses. The analysis of data reveals that on a four-character level (Fxx.x), the 10 most often used diagnostic categories represent 40% of all main diagnoses, and 70% on a three-character level (Fxx.-). There are 32 specific diagnostic categories on a four-character level which are not used at all and 121 which are used less frequently than 0.1% in inpatient and outpatient treatment. The study shows that the ICD-10 classification is in use in a variety of treatment settings worldwide. Further results and limitations of this study are discussed against the background of transcultural differences.