Comparative study of affective disorders in three Asian countries. I. Differences in diagnostic classification

Area of Science:

• Psychiatry
• Epidemiology
• Cross-cultural research

Background:

• Affective disorders represent a significant global health burden.
• Low reported prevalence rates of depressive disorders in Asia necessitate further investigation.
• International collaborative studies are crucial for understanding global mental health trends.

Purpose of the Study:

• To standardize symptom evaluation for patients with depression as a preliminary step for a large collaborative study on affective disorders.
• To investigate factors contributing to the low reported prevalence of depressive disorders in Asia.
• To compare diagnostic practices across different cultural contexts.

Main Methods:

• Symptom evaluation standardization was conducted across three international centers: Nagasaki, Shanghai, and Seoul.
• Psychiatric symptoms were evaluated using a standardized approach.
• Diagnostic discrepancies were analyzed based on the International Classification of Diseases, 9th Revision (ICD-9).

Main Results:

• No significant differences were found in the evaluation of psychiatric symptoms among the three centers.
• However, notable differences emerged in diagnoses assigned using ICD-9 criteria.
• Nagasaki predominantly diagnosed 'affective psychosis depression,' while Shanghai favored 'neurotic disorder,' with Seoul showing no significant diagnostic tendency.

Conclusions:

• Standardized symptom evaluation is achievable across diverse cultural settings.
• Significant diagnostic variations exist even with standardized symptom assessment, impacting prevalence rates.
• These findings underscore the importance of addressing diagnostic variability in future international collaborative studies on affective disorders.