The World Health Organization Department of Mental Health and Substance Abuse has been conducting an active program of field studies and international surveys as a part of developing the ICD-11 classification of mental and behavioural disorders.

A key priority for WHO is that the ICD-11 serve as a more effective tool for reducing the global disease burden of mental and behavioural disorders.

In support of this objective, a major goal of the revision is to improve the classification's clinical utility. To provide relevant information on clinical utility, WHO has worked to assess the perspectives of practicing clinicians throughout the world.

Two global field studies have been conducted regarding how clinicians conceptualize the relationships among mental disorders based on their clinical experience. The first study included 1371 psychiatrists and psychologists from 64 countries, and used a paired comparisons methodology. The second study used a ‘folk taxonomy’ method, and was administered with 480 psychiatrists and psychologists in Brazil, China, India, Japan, Mexico, Nigeria, Spain, and the USA.

Highly similar results were obtained across two large international studies using different methodologies. Clinicians’ conceptualizations are rational and highly stable, regardless of country, language, profession, and country income level. Differences between clinicians’ judgments and classification system are not due to idiosyncratic clinician error, but rather to systematic differences.

The presentation will discuss how empirical data on clinician judgments are contributing to the development of a new and more clinically useful classification of mental disorders, without sacrificing validity.