A revised mental health classification for use in general medical settings: the ICD11-PHC.

The World Health Organization (WHO) was aware that many hospital doctors and general practitioners did not use the detailed ICD-10 classification of mental and behavioural disorders (WHO, 1993), which had been produced for mental health professionals, and so it commissioned a specially modified version suitable for general medical settings. The new system was required to have modified - but not exact - equivalence to the main classification, and to consist of clinical descriptions rather than operational criteria for each of the proposed categories. The system would describe typical presenting complaints for each category in this setting, as well as the diagnostic features and the differential diagnosis for each disorder. An important new feature of the system was that it included the information that should be given to the patient and family, described the effective psychological and drug treatments and gave indications for specialist referral.