Sakashita Chika, Slade Tim, Andrews Gavin
Roads and Traffic Authority, Surry Hills, NSW, Australia.
Aust N Z J Psychiatry. 2007 Jan;41(1):17-23. doi: 10.1080/00048670601050440.
The aim of the current study was to examine two major assumptions behind the DSM-IV diagnosis of major depressive episode (MDE): that depression represents a distinct category defined by a valid symptom threshold, and that each depressive symptom contributes equally to the diagnosis.
Data were from the Australian National Survey of Mental Health and Wellbeing. Participants consisted of a random population-based sample of 10 641 community volunteers, representing a response rate of 78%. DSM-IV diagnoses of MDE and other mental disorders were obtained using the Composite International Diagnostic Interview, version 2.0. Analyses were carried out on the subsample of respondents who endorsed either depressed mood or loss of interest (n =2137). Multivariate linear regression analyses examined the relationship between the number and type of symptoms and four independent measures of impairment.
The relationship between the number of depressive symptoms and the four measures of impairment was purely linear. Three individual symptoms (sleep problems, energy loss, and psychomotor disturbance) were all independent predictors of three of the four measures of impairment.
Counting symptoms alone is limited in guiding a clear diagnostic threshold. The differential impact of individual symptoms on impairment suggests that impairment levels may be more accurately estimated by weighting the particular symptoms endorsed.
本研究旨在检验《精神疾病诊断与统计手册》第四版（DSM-IV）中重度抑郁发作（MDE）诊断背后的两个主要假设：抑郁代表由有效症状阈值定义的独特类别，且每种抑郁症状对诊断的贡献相同。
数据来自澳大利亚全国心理健康与幸福调查。参与者包括基于随机抽样的10641名社区志愿者，应答率为78%。使用综合国际诊断访谈2.0版获得MDE和其他精神障碍的DSM-IV诊断。对认可情绪低落或兴趣丧失的受访者子样本（n = 2137）进行分析。多变量线性回归分析检验了症状数量和类型与四种独立损害测量指标之间的关系。
抑郁症状数量与四种损害测量指标之间的关系完全是线性的。三种个体症状（睡眠问题、精力丧失和精神运动性障碍）都是四种损害测量指标中三种指标的独立预测因素。
仅依靠计算症状数量在指导明确诊断阈值方面存在局限性。个体症状对损害的不同影响表明，通过对认可的特定症状进行加权，可能更准确地估计损害水平。
