The development of the ICD-11 CDDG over the past decade, based on the principles of clinical utility and global applicability, has been the most broadly international, multilingual, multidisciplinary and participative revision process ever implemented for a classification of mental disorders. Innovations in the ICD-11 include the provision of consistent and systematically characterized information, the adoption of a lifespan approach, and culture-related guidance for each disorder. Dimensional approaches have been incorporated into the classification, particularly for personality disorders and primary psychotic disorders, in ways that are consistent with current evidence, are more compatible with recovery-based approaches, eliminate artificial comorbidity, and more effectively capture changes over time. Here we describe major changes to the structure of the ICD-11 classification of mental disorders as compared to the ICD-10, and the development of two new ICD-11 chapters relevant to mental health practice. We illustrate a set of new categories that have been added to the ICD-11 and present the rationale for their inclusion. Finally, we provide a description of the important changes that have been made in each ICD-11 disorder grouping. This information is intended to be useful for both clinicians and researchers in orienting themselves to the ICD-11 and in preparing for implementation in their own professional contexts.

Early-life serotonin [5-hydroxytryptamine (5-HT)] signaling modulates brain development, which impacts adult behavior, but 5-HTsensitive periods, neural substrates, and behavioral consequences remain poorly understood. Here we identify the period ranging from postnatal day 2 (P2) to P11 as 5-HT sensitive, with 5-HT transporter (5-HTT) blockade increasing anxiety-and depression-like behavior, and impairing fear extinction learning and memory in adult mice. Concomitantly, P2-P11 5-HTT blockade causes dendritic hypotrophy and reduced excitability of infralimbic (IL) cortex pyramidal neurons that normally promote fear extinction. By contrast, the neighboring prelimbic (PL) pyramidal neurons, which normally inhibit fear extinction, become more excitable. Excitotoxic IL but not PL lesions in adult control mice reproduce the anxiety-related phenotypes. These findings suggest that increased 5-HT signaling during P2-P11 alters adult mPFC function to increase anxiety and impair fear extinction, and imply a differential role for IL and PL neurons in regulating affective behaviors. Together, our results support a developmental mechanism for the etiology and pathophysiology of affective disorders and fear-related behaviors.

The World Health Organization (WHO) Department of Mental Health and Substance Abuse has developed a systematic program of field studies to evaluate and improve the clinical utility of the proposed diagnostic guidelines for mental and behavioral disorders in the Eleventh Revision of the International Classification of Diseases and Related Health Problems (ICD-11). The clinical utility of a diagnostic classification is critical to its function as the interface between health encounters and health information, and to making the ICD-11 be a more effective tool for helping the WHO's 194 member countries, including the United States, reduce the global disease burden of mental disorders. This article describes the WHO's efforts to develop a science of clinical utility in regard to one of the two major classification systems for mental disorders. We present the rationale and methodologies for an integrated and complementary set of field study strategies, including large international surveys, formative field studies of the structure of clinicians' conceptualization of mental disorders, case-controlled field studies using experimental methodologies to evaluate the impact of proposed changes to the diagnostic guidelines on clinicians' diagnostic decision making, and ecological implementation field studies of clinical utility in the global settings in which the guidelines will ultimately be implemented. The results of these studies have already been used in making decisions about the structure and content of ICD-11. If clinical utility is indeed among the highest aims of diagnostic systems for mental disorders, as their developers routinely claim, future revision efforts should continue to build on these efforts. (PsycINFO Database Record

Background The World Health Organization (WHO) International Classification of Diseases and Related Health Problems (ICD) is used globally by 194 WHO member nations. It is used for assigning clinical diagnoses, providing the framework for reporting public health data, and to inform the organization and reimbursement of health services. Guided by overarching principles of increasing clinical utility and global applicability, the 11th revision of the ICD proposes major changes that incorporate empirical advances since the previous revision in 1992. To test recommended changes in the Mental, Behavioral, and Neurodevelopmental Disorders chapter, multiple vignette-based case-controlled field studies have been conducted which examine clinicians’ ability to accurately and consistently use the new guidelines and assess their overall clinical utility. This manuscript reports on the results from the study of the proposed ICD-11 guidelines for feeding and eating disorders (FEDs). Method Participants were 2288 mental health professionals registered with WHO’s Global Clinical Practice Network. The study was conducted in Chinese, English, French, Japanese, and Spanish. Clinicians were randomly assigned to apply either the ICD-11 or ICD-10 diagnostic guidelines for FEDs to a pair of case vignettes designed to test specific clinical questions. Clinicians selected the diagnosis they thought was correct for each vignette, evaluated the presence of each essential feature of the selected diagnosis, and the clinical utility of the diagnostic guidelines. Results The proposed ICD-11 diagnostic guidelines significantly improved accuracy for all FEDs tested relative to ICD-10 and attained higher clinical utility ratings; similar results were obtained across all five languages. The inclusion of binge eating disorder and avoidant-restrictive food intake disorder reduced the use of residual diagnoses. Areas needing further refinement were identified. Conclusions The proposed ICD-11 diagnostic guidelines consistently outperformed ICD-10 in distinguishing cases of eating disorders and showed global applicability and appropriate clinical utility. These results suggest that the proposed ICD-11 guidelines for FEDs will help increase accuracy of public health data, improve clinical diagnosis, and enhance health service organization and provision. This is the first time in the revision of the ICD that data from large-scale, empirical research examining proposed guidelines is completed in time to inform the final diagnostic guidelines.

The dorsoventral axis of the Drosophila egg is established by dorsally localized activation of the epidermal growth factor receptor (Egfr)in the ovarian follicular epithelium. Subsequent positive- and negative-feedback regulation generates two dorsolateral follicle cell primordia that will produce the eggshell appendages. A dorsal midline domain of low Egfr activity between the appendage primordia defines their dorsal boundary, but little is known about the mechanisms that establish their ventral limit. We demonstrate that the transcriptional repressor Capicua is required cell autonomously in ventral and lateral follicle cells to repress dorsal fates, and functions in this process through the repression of mirror. Interestingly, ectopic expression of mirror in the absence of capicua is observed only in the anterior half of the epithelium. We propose that Capicua regulates the pattern of follicle cell fates along the dorsoventral axis by blocking the induction of appendage determinants, such as mirror, by anterior positional cues.