Zimmerman Mark, McGlinchey Joseph B, Young Diane, Chelminski Iwona
Department of Psychiatry and Human Behavior, Brown University School of Medicine, Rhode Island Hospital, Providence, Rhode Island 02905, USA.
J Nerv Ment Dis. 2006 May;194(5):313-7. doi: 10.1097/01.nmd.0000217806.16329.ff.
All criteria used to diagnose a psychiatric disorder should contribute to distinguishing cases from noncases. The principal of parsimony argues for defining a disorder with as few criteria as possible. Thus, criteria that do not contribute to the case-noncase distinction should be eliminated from the list of defining features because they unnecessarily increase the complexity of the definition of the disorder. In polythetically defined disorders such as major depressive disorder (MDD), diagnosis is based on the presence of a minimum number of features from a list. For a criterion to be retained on such a list, it should contribute to distinguishing between individuals with and without MDD. Simply demonstrating that a criterion is significantly more common in individuals with MDD than individuals without MDD is not a sufficient demonstration of its necessity. Rather, to demonstrate an impact on diagnosis, it should be shown that eliminating the criterion from the list results in individuals being reclassified from a case to a noncase. A criterion does not contribute to determining caseness if its elimination does not result in diagnostic reclassification. The goal of this report from the Rhode Island Hospital Methods to Improve Diagnostic Assessment and Services project was to determine if any of the criteria of MDD are candidates for elimination because of their lack of impact on diagnosis. The results indicated that the symptoms of increased weight, decreased weight, and indecisiveness rarely influenced diagnostic classification and thus are candidates for elimination.
用于诊断精神疾病的所有标准都应有助于区分病例与非病例。简约原则主张用尽可能少的标准来定义一种疾病。因此，那些无助于区分病例与非病例的标准应从定义特征列表中剔除，因为它们不必要地增加了疾病定义的复杂性。在诸如重度抑郁症（MDD）这样的多标准定义的疾病中，诊断基于从列表中选取的最少数量的特征的存在。要将一个标准保留在这样的列表中，它应该有助于区分患有和未患有MDD的个体。仅仅证明一个标准在患有MDD的个体中比未患有MDD的个体中显著更常见，并不足以证明其必要性。相反，为了证明对诊断有影响，应该表明从列表中剔除该标准会导致个体从病例重新分类为非病例。如果剔除一个标准不会导致诊断重新分类，那么该标准对确定病例状态没有贡献。这份来自罗德岛医院改善诊断评估与服务项目方法的报告的目标是确定MDD的任何标准是否因对诊断缺乏影响而可被剔除。结果表明，体重增加、体重减轻和犹豫不决的症状很少影响诊断分类，因此是可被剔除的候选标准。
