J Ment Health. 2023 Nov 10:1-9. doi: 10.1080/09638237.2023.2278107. Online ahead of print.
BACKGROUND: Latent disease classification is currently the accepted approach to mental illness diagnosis. In the United States, this takes the form of the Diagnostic and Statistical Manual of Mental Disorders-5-Text Revision (DSM-5-TR). Latent disease classification has been criticized for reliability and validity problems, particularly regarding diagnostic heterogeneity. No authors have calculated the scope of the heterogeneity problem of the entire DSM-5-TR.
AIMS: We addressed this issue by calculating the unique diagnostic profiles that exist for every DSM-5-TR diagnosis.
METHODS: We did this by applying formulas previously used in smaller heterogeneity analyses to all diagnoses within the DSM-5-TR.
RESULTS: We found that there are 10,130,814 ways to be diagnosed with a mental illness using DSM-5-TR criteria. When specifiers are considered, this number balloons to over 161 septillion unique diagnostic presentations (driven mainly by bipolar II disorder). Additionally, there are 1,951,065 ways to present with psychiatric symptoms, yet not meet diagnostic criteria.
CONCLUSIONS: Latent disease classification leads to considerable heterogeneity in possible presentations. We provide examples of how latent disease classification harms research and treatment programs. We echo recommendations for the dismissal of latent disease classification as a mental illness diagnostic program.