What are the strengths and weaknesses of the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM‑5‑TR) and the International Classification of Diseases, Eleventh Revision (ICD‑11) in diagnosing hallucinogen‑related disorders?

Diagnostic Strengths and Weaknesses of DSM-5-TR and ICD-11 for Hallucinogen-Related Disorders

Both DSM-5-TR and ICD-11 lack biological validation for hallucinogen-related disorders, resulting in diagnostically heterogeneous categories that cannot guide treatment selection based on underlying pathophysiology, though ICD-11 demonstrates superior clinical utility with 82.5–83.9% of clinicians rating it as quite or extremely easy to use, accurate, clear, and understandable. 1

DSM-5-TR Strengths

• The categorical framework with explicit symptom thresholds promotes reliable identification of hallucinogen-related disorder cases and facilitates insurance reimbursement and administrative billing. 2
• Integration with ICD-10-CM coding allows seamless cross-referencing for billing and medical-record documentation in clinical practice. 2
• The categorical structure enables rapid communication among clinicians and supports justification of treatment plans for administrative purposes. 2
• The system is specifically designed for research settings, providing standardized criteria that facilitate scientific investigation. 3

DSM-5-TR Weaknesses

• Approximately 60% of individuals presenting with hallucinogen-related behaviors may not meet exact DSM-5-TR criteria, leading to classification as "Not Otherwise Specified." 2
• The criteria lack biological validation, producing heterogeneous diagnostic groups that cannot guide treatment selection based on underlying neurobiological mechanisms. 2
• The symptom-based approach offers no guidance for choosing interventions that target specific pathophysiological processes. 2
• Cultural insensitivity may exclude individuals whose substance-related behaviors manifest differently across diverse ethnic contexts. 2
• The system relies on subjective terms without operational definitions, increasing the risk of pathologizing normal responses to hallucinogen exposure. 4

ICD-11 Strengths

• In multinational field studies, 82.5–83.9% of clinicians rated ICD-11 as "quite" or "extremely" easy to use, accurate, clear, and understandable—significantly outperforming ICD-10. 1, 2
• ICD-11 demonstrated higher diagnostic accuracy and faster time to diagnosis compared with ICD-10 in vignette-based assessments across multiple disorder categories. 1, 4
• The dimensional symptom-assessment model permits rating severity across multiple domains at each visit, supporting flexible treatment planning without strict temporal symptom counts. 2, 5
• Longitudinal coding of episode status (first episode, multiple episodes, continuous course; currently symptomatic, partial remission, full remission) enables monitoring of hallucinogen-disorder trajectories over time. 2, 5
• The stepwise diagnostic approach combines categorical classification for routine clinical use with dimensional assessments for specialized settings and research. 2
• Dimensional psychometric profiles provide nuanced information beyond overall severity, informing treatment decisions particularly for psychotherapy. 2
• The system is designed to improve clinical utility in real-world practice settings rather than primarily serving research purposes. 3
• For substance use disorders specifically, ICD-11 shows excellent concordance with ICD-10 and DSM-IV (all κ ≥ 0.9), indicating strong diagnostic consistency. 6

ICD-11 Weaknesses

• Field-study methodology may be affected by selection bias, as clinicians favorable to the new system were more likely to participate in online studies, potentially inflating performance estimates. 1, 5
• Vignette-based validation used prototypical cases that do not capture the complexity of real-world presentations, including multiple comorbidities and cultural variations. 1, 5
• The system remains symptom-based without biological grounding, limiting its capacity to inform biologically-targeted interventions. 2, 5
• Dimensional symptom specifiers lack clear operational definitions for "excessive" or "disproportionate" behavior, risking pathologization of normal developmental or cultural variation. 2
• Revisions from ICD-10 to ICD-11 were relatively modest, with no paradigm shift in conceptualizing substance-related disorders. 1, 2
• Concordance between ICD-11 and DSM-5 varies from good to poor depending on severity categories, with particularly low agreement for harmful use versus mild use disorder. 6
• Very low endorsement rates were observed for the new ICD-11 "harm to others" feature in harmful use, raising questions about its diagnostic validity. 6

Shared Limitations Across Both Systems

• Both DSM-5-TR and ICD-11 lack neurobiological validation, resulting in biologically heterogeneous groups within the same diagnostic category that cannot direct treatment based on underlying mechanisms. 2, 5, 4
• Neither system can guide selection of biologically-targeted interventions because they classify based on observable symptoms rather than pathophysiology. 1, 2
• Both systems are categorical at their core, classifying mental phenomena based on self-reported or clinically observable symptoms rather than dimensional constructs. 1
• The structure of neither system is based on neurobiology, and large biological heterogeneity exists within diagnostic categories. 1
• Changes between versions have been relatively modest despite extensive revision processes, maintaining symptom-based rather than pathophysiology-based classification. 5

Clinical Implementation Considerations

• For insurance billing, reimbursement, and treatment authorization, use DSM-5-TR's categorical diagnosis, which aligns with most administrative processes in the United States. 2, 4
• When dimensional symptom tracking and longitudinal monitoring are essential for hallucinogen-related disorders, prioritize ICD-11 because of its superior ease of use and ability to code episode status and symptom severity. 4
• A hybrid documentation approach can be employed: record symptom severity across ICD-11 domains at each assessment while retaining the DSM-5-TR categorical label for billing purposes. 4
• Recognize that most clinicians use diagnostic classifications primarily for administrative or billing purposes (68.1%), with only 57.4% systematically going through diagnostic guidelines to determine applicability to individual patients. 7
• Both classifications are rated most useful for assigning a diagnosis, communicating with other healthcare professionals, and teaching, but least useful for treatment selection and determining prognosis. 7
• Approximately 12% of ICD-10 users and 19% of DSM users employ "residual" categories (other/unspecified) often or routinely, most commonly when clinical presentations do not conform to specific diagnostic categories. 7

Common Pitfalls to Avoid

• Do not exclude patients with atypical presentations who fail to meet exact categorical thresholds if they exhibit core features of hallucinogen-related harm or dependence; the broadened criteria in both systems accommodate partial presentations. 4
• Avoid over-reliance on categorical labels alone without considering dimensional severity, as this limits treatment planning and prognostic assessment. 2, 5
• Do not assume that diagnostic categories reflect biologically homogeneous groups suitable for mechanism-based treatment selection. 1, 2
• Recognize that field studies may not accurately reflect diagnostic decision-making in routine care due to participant selection bias and the artificiality of vignette-based assessments. 1, 5