Stratford Paul W, Kennedy Deborah M, Riddle Daniel L
School of Rehabilitation Science, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
J Clin Epidemiol. 2009 Mar;62(3):347-52. doi: 10.1016/j.jclinepi.2008.06.008. Epub 2008 Oct 1.
We propose a study design to evaluate the ability of measures to assess physical function relatively independent of pain. We illustrate the design using data from patients scheduled for total hip (THA) or knee (TKA) arthroplasty.
A repeated-measure study design was developed and applied to patients undergoing THA or TKA. A performance battery (PB) (walking, stair, and timed-up-and-go) was used as the gold standard measure for "physical function." Recent evidence indicates physical performance deteriorates 1 month after surgery compared to presurgical measures and patients with THA deteriorate to a greater extent than patients with TKA. Our design assessed whether the results from self-report measures (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] and the Lower Extremity Functional Scale [LEFS]) of physical function were consistent with changes found using the PB.
The performance measures demonstrated significant Occasion (pre- to 1 month postarthroplasty) and Group (hip vs. knee)-by-Occasion effects; the LEFS showed a significant Occasion effect; and the WOMAC PF showed neither.
Our findings support the proposed design in that the PB was more sensitive to change than the self-report measures.
我们提出一项研究设计，以评估各项测量方法相对独立于疼痛来评估身体功能的能力。我们使用计划进行全髋关节置换术（THA）或全膝关节置换术（TKA）的患者数据来说明该设计。
开发了一项重复测量研究设计并应用于接受THA或TKA的患者。一套表现评估组合（PB）（步行、上下楼梯和定时起立行走测试）被用作“身体功能”的金标准测量方法。最近的证据表明，与术前测量相比，术后1个月身体表现会变差，且THA患者比TKA患者变差的程度更大。我们的设计评估了身体功能的自我报告测量方法（西安大略和麦克马斯特大学骨关节炎指数[WOMAC]以及下肢功能量表[LEFS]）的结果是否与使用PB发现的变化一致。
表现测量显示出显著的时期（关节置换术前至术后1个月）以及组（髋关节置换术与膝关节置换术）×时期效应；LEFS显示出显著的时期效应；而WOMAC身体功能部分则未显示出这些效应。
我们的研究结果支持所提出的设计，因为PB对变化比自我报告测量方法更敏感。
