Diagnostic content validation of nursing diagnoses is a recommended means to confirm the defining characteristics necessary to establish a specific nursing diagnosis. The diagnostic content validity model has been used in numerous studies to develop lists of major and minor defining characteristics recommended by experts as being present in patients with specific diagnoses. The authors provide an overview of the diagnostic content validity model, review the meaning and purposes of content validity, discuss problems with information processing, and suggest revisions to the diagnostic content validity model. Incorporation of these changes may improve the usability of nursing diagnoses in clinical practice, education, and research.