Anxiety and Fear-Related Disorders in the ICD-11: Results from a Global Case-controlled Field Study.

BACKGROUND: This article reports the results of one of a series of global field studies implemented by the World Health Organization (WHO) to evaluate the accuracy, clinical utility, and global applicability of the new diagnostic guidelines for Mental, Behavioural and Neurological Disorders included in the next version of WHO's International Classification of Diseases (ICD-11). AIMS OF THE STUDY: The purpose of this study was to compare the diagnostic accuracy and clinical utility ratings of global clinicians implementing the ICD-11 diagnostic guidelines for Anxiety and Fear-Related Disorders, relative to those applying ICD-10 guidelines. The study also aimed to identify elements of the guidelines that required further refinement or clarification. METHODS: 1840 global mental health professionals registered with WHO's Global Clinical Practice Network completed the study in one of six study languages. Participants were randomly assigned to apply either the ICD-11 or ICD-10 guidelines to diagnose standardized case vignettes, and to rate the clinical utility of their assigned guidelines. RESULTS: ICD-11's diagnostic accuracy and clinical utility were equivalent or superior to that of ICD-10. Global clinicians were significantly more accurate in diagnosing Generalized Anxiety Disorder, Specific Phobia and adult cases of Separation Anxiety Disorder when using ICD-11 and provided high clinical utility ratings for these disorders. Clinicians also found the ICD-11 guidelines easy to use, clear, and a good fit to patients they see in their clinical practice. However, clinicians had difficulty with distinguishing the boundary between disorder and normality for subthreshold cases of anxiety, and also with applying the new ICD-11 guidelines on panic attacks. CONCLUSIONS: The new diagnostic guidelines for Anxiety Disorders in ICD-11 can be applied in an acceptably consistent manner by global clinicians and perform as well or better than the previous guidelines for ICD-10. Study findings also helped identify aspects of the ICD-11 guidelines that required refinement prior to their publication and areas that should be emphasized in training programs.