Dirks H F, Wunder J, Reynolds J, Basse R, Kinsman R, Jones N
Colorado Rehabilitation Institute, Psychometric Designs Inc., Denver, USA.
Psychother Psychosom. 1996;65(3):153-7. doi: 10.1159/000289068.
Waddell and colleagues have identified a series of nonorganic signs which may appear in low back pain patients. The occurrence of these signs helps predict nonphysiological factors in the etiology of the pain. This study describes the development of the Waddell Equivalency Scale (WES) which elicits comparable information from patients with pain at other sites.
One hundred fifty patients presenting to a comprehensive pain clinic with low back pain were evaluated by physicians for Waddell signs and by psychologists using the Pain Presentation Inventory (PPI) developed by Psychometric Designs Inc. From three scales of the PPI, correlation, analysis of variance and multiple regression identified a formula which predicted Waddell signs from the PPI. The study was replicated on a new sample of 150 patients with almost identical results. The two samples were combined, again with highly similar results. An interpretive scheme was devised for use of the WES scale.
The WES score derived from three scales of the PPI predicts the number of Waddell signs elicited from low back pain patients. Since it comes from a paper-and-pencil test rather than a physical examination, it can be used with patients whose pain locus is other than the back.
Behavioral expectations and treatment plans, à la Waddell, can now be applied to patients with other than low back pain. Clinical application of the WES information over a variety of pain populations will be required to determine the parameters of its usefulness.
瓦德尔及其同事已识别出一系列可能出现在腰痛患者身上的非器质性体征。这些体征的出现有助于预测疼痛病因中的非生理因素。本研究描述了瓦德尔等效量表（WES）的开发过程，该量表可从其他部位疼痛的患者身上获取可比信息。
150名因腰痛前往综合疼痛诊所就诊的患者接受了医生对瓦德尔体征的评估，以及心理学家使用心理测量设计公司开发的疼痛表现量表（PPI）进行的评估。从PPI的三个量表中，通过相关性分析、方差分析和多元回归确定了一个从PPI预测瓦德尔体征的公式。该研究在150名新患者样本上重复进行，结果几乎相同。将两个样本合并，结果依然高度相似。为使用WES量表设计了一种解释方案。
从PPI的三个量表得出的WES分数可预测从腰痛患者身上引出的瓦德尔体征数量。由于它来自纸笔测试而非体格检查，因此可用于疼痛部位不在背部的患者。
现在，类似于瓦德尔的行为预期和治疗计划可应用于非腰痛患者。需要在各种疼痛人群中对WES信息进行临床应用，以确定其有用性的参数。
