HEE: Developing a reference protocol for expert elicitation in health care decision making

在卫生保健预算有限的地方，有关使用治疗的困难决定是由决策者做出的。他们通常会考虑每种替代疗法的好处，并选择一种有望最大限度地促进健康的疗法。当预算有限时，花在新治疗上的钱将意味着其他患者可能无法获得相同水平的医疗保健。决策者需要权衡健康收益和损失(成本效益)。为了确定成本效益，决策通常基于感兴趣的疾病和所给予的任何治疗的数学模型。模型的输入是必需的，例如心脏病发作的风险。由于证据的不确定性，往往不能确切地知道干预的成本效益。然而，重要的是，成本效益估计中的不确定性应反映在所进行的任何分析中。如果不是，任何决定都可能具有误导性。在无法获得信息的情况下，专家的经验至关重要。专家的信仰可以被正式收集和记录的过程就是“专家启发”。专家启发已被用于许多领域，包括火山学和天气预报。有许多备选议定书(良好做法指南)可用于设计、实施和使用专家启发，但尚不清楚其中是否可以适当地用于利用成本效益证据为决策提供信息。该项目的总体目标是建立一个参考议定书，以征求专家的判断，为卫生保健决策提供信息。为了做到这一点，我们计划了一系列的工作包：WP1评估现有的启发分发协议我们将批判性地审查可用的启发指南；这将包括已出版和未出版的文献。每种方法的原理将根据卫生保健决策的一套要求进行评估。在审查发现知识差距的情况下，对拟议的替代方法进行有针对性的搜索，将能够查明每种选择的优缺点，并确定其应用于成本效益分析的任何潜在制约因素。WP2引出分布来表示参数的不确定性为了考虑卫生保健决策过程中的不确定性，引出的判断需要反映专家所拥有的不完善的知识。在WP1中，我们将考虑替代方法，以避免专家表达变异性。此外，还有其他方法来得出判断(集体协商一致方法和个别专家方法)，这些方法在表示不确定性的程度方面有所不同。为了给启发式方法的选择提供依据，我们将进行一项实验。WP3理解并适当描述专家之间的差异在生成成本效益估计时，重要的是纳入一系列专家的投入。必须将这些方法结合起来，并有其他方法来做到这一点：协商一致方法和个别方法。已经对各种方法进行了比较；然而，结果并不明确地支持一种方法优于另一种方法，也不清楚哪种方法在专家不确定性和跨专家可变性方面都能最好地代表情况。在这一工作包中，我们将进行一项实验，以探索共识方法产生不确定性表达的能力，特别是在专家之间的差异也很重要的情况下。这项实验还将允许我们探索汇集个人判断的不同方法。评估：为了证明WPS 1-3中开发的协议的有效性，我们将使用开发的协议进行启发练习，以实时为决策过程提供信息。约克是NICES技术和诊断评估流程的评估组。我们将进行一次启发练习，以告知当前的决定。

Where the budget for health care is limited, difficult decisions about the use of treatments are made by decision makers. They usually consider the benefits of each alternative treatment and select the one that is expected to maximise health. When the budget is limited, money spent on a new treatment will mean other patients may not have access to the same level of health care. A decision maker needs to weigh the health gains with the losses (cost-effectiveness). To establish cost-effectiveness, decisions are usually based on a mathematical model of the disease of interest and any treatments given. Inputs to a model, for example risk of a heart attack, are required. Due to uncertainty in the evidence, the cost-effectiveness of an intervention is often not known with certainty. However, it is important that the uncertainty in cost-effectiveness estimates is reflected in any analysis conducted. If not, any decisions can be potentially misleading. In situations where information is unavailable, the experience of experts is essential. The process by which the beliefs of experts can be formally collected and recorded is "expert elicitation". Expert elicitation has been used in many areas including volcanology and weather forecasts. A number of alternative protocols (guides to good practice) are available for the design, conduct and use of expert elicitation, but it is not clear if any of these can appropriately be used to inform decisions using cost-effectiveness evidence. The overall aim of this project is to establish a reference protocol for the elicitation of experts' judgements to inform health care decision making. To do this we plan a series of work packages:WP1 Appraisal of existing protocols for eliciting distributions We will critically review available guidance for elicitation; this will include published and unpublished literature. The principles of each method will be appraised in light of a set of requirements for health care decision making. Where the review identifies gaps in knowledge, targeted searches on the alternative methods proposed will allow advantages and disadvantages of each choice to be identified and any potential constraints to their application for cost-effectiveness analyses to be established. WP2 Eliciting distributions to represent parameter uncertaintyIn order to consider uncertainty in the health care decision making process, judgements elicited need to reflect the imperfect knowledge experts have. Within WP1 we will consider alternative methods to avoid experts expressing variability. In addition, there are alternative approaches to elicit judgements (group consensus and individual expert approaches) and these differ in terms of how well uncertainty is represented. To inform the choice of approach to elicitation we will conduct an experiment. WP3 Understanding and appropriately characterising between-expert variationIt is important to include inputs from a range of experts in generating estimates of cost-effectiveness. These must be combined and there are alternative methods to do this: consensus and individual methods. There has been comparison of methods; however, results do not clearly support one approach over another and it is unclear which method best represents both within expert uncertainty and across expert variability. Within this work-package, we will conduct an experiment to explore the ability of consensus methods to generate expressions of uncertainty, particularly where between-expert variation is also important. The experiment will also allow us to explore different methods of pooling individual judgements. EVALUATION: To demonstrate the usefulness of the protocol developed in WPs 1-3, we will conduct an elicitation exercise using the protocol developed to inform a decision making process in real time. York is an Assessment Group for NICEs technology and diagnostics assessment processes. We will conduct an elicitation exercise to inform a current decision.