Division of Rheumatology, Department of Medicine, Toronto Western Hospital, University Health Network, Toronto, Ontario M5T 2S8, Canada.
J Clin Epidemiol. 2010 Apr;63(4):370-83. doi: 10.1016/j.jclinepi.2009.08.005. Epub 2009 Nov 18.
Bayesian inference has the advantage of formally incorporating prior beliefs about the effect of an intervention into analyses of treatment effect through the use of prior probability distributions or "priors." Multiple methods to elicit beliefs from experts for inclusion in a Bayesian study have been used; however, the measurement properties of these methods have been infrequently evaluated. The objectives of this study were to evaluate the feasibility, validity, and reliability of a belief elicitation method for Bayesian priors.
A single-center, cross-sectional study using a sample of academic specialists who treat pulmonary hypertension patients was conducted to test the feasibility, face and construct validity, and reliability of a belief elicitation method. Using this method, participants expressed the probability of 3-year survival with and without warfarin. Applying adhesive dots or "chips," each representing 5% probability, in "bins" on a line, participants expressed their uncertainty and weight of belief about the effect of warfarin on 3-year survival.
Of the 12 participants, 11 (92%) reported that the belief elicitation method had face validity, 10 (83%) found the questions clear, and 11 (92%) found the response option easy to use. The median time to completion was 10 minutes (5-15 minutes). Internal validity testing found moderate agreement (weighted kappa=0.54-0.57). The intraclass correlation coefficient for test-retest reliability was 0.93.
This method of belief elicitation for Bayesian priors is feasible, valid, and reliable. It can be considered for application in Bayesian clinical studies.
贝叶斯推断的优势在于通过使用先验概率分布或“先验”，将对干预效果的先验信念正式纳入治疗效果分析中。已经使用了多种从专家那里获取信念并将其纳入贝叶斯研究的方法；然而，这些方法的测量特性很少得到评估。本研究的目的是评估一种用于贝叶斯先验的信念 elicitation 方法的可行性、有效性和可靠性。
一项单中心、横断面研究使用了治疗肺动脉高压患者的学术专家样本，以测试一种信念 elicitation 方法的可行性、表面和结构有效性以及可靠性。使用这种方法，参与者表达了有和没有华法林的 3 年生存率的概率。参与者通过在线上的“bin”中使用表示 5%概率的粘性点或“chips”来表达他们对华法林对 3 年生存率的影响的不确定性和置信度。
在 12 名参与者中，有 11 名（92%）表示信念 elicitation 方法具有表面有效性，10 名（83%）认为问题清晰，11 名（92%）认为响应选项易于使用。完成的中位数时间为 10 分钟（5-15 分钟）。内部有效性测试发现了中度一致性（加权 kappa=0.54-0.57）。测试-重测可靠性的组内相关系数为 0.93。
这种用于贝叶斯先验的信念 elicitation 方法是可行、有效和可靠的。它可以考虑应用于贝叶斯临床研究。
