Taxonomy and utility in the diagnostic classification of mental disorders.

Objective One strategy for improving the clinical utility of mental health diagnostic systems is to better align them with how clinicians conceptualize psychopathology in practice. This approach was used in International Classification of Diseases 11th Revision (ICD-11) development, but its underlying assumption-a link between taxonomic "fit" and clinical utility-remains untested. Methods Using data from global mental health clinician samples (combined N = 5404), we investigated the association between taxonomic fit and clinical utility in mental disorder categories. Results The overall association between fit and utility was positive (r = 0.19) but statistically not different from zero (95% confidence interval [CI]: -0.06, 0.43) in this small sample (N = 39 ICD/DSM categories). However, a positive association became clear after correcting for outliers (r = 0.34 [0.05, 0.58] or higher). Further insights were apparent for specific diagnoses given their locations in the scatterplot. Conclusions Results suggest a positive link between taxonomic fit and clinical utility in mental disorder diagnoses, highlighting future research directions.