Use of expert judgment in exposure assessment. Part I. Characterization of personal exposure to benzene.
Use of expert judgment in exposure assessment. Part I. Characterization of personal exposure to benzene.
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在暴露评估中使用专家判断。
DOI：
10.1038/sj.jea.7500171
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
MacIntosh,D
中科院分区：
文献类型：
--
作者：
Walker,KD;Evans,JS;MacIntosh,D
本文介绍了一项研究的第一阶段的结果，作为国家人类暴露评估调查（NHEXAS）的一个组成部分，展示了使用专家主观判断引出技术来表征苯环境暴露的程度和不确定性。在关于暴露研究或监管控制的价值的决定中，不确定性的表征可以发挥影响作用。当有足够的相关数据时，经典的不确定性表征方法可能就足够了。然而，通常情况下，数据既不丰富，也不直接相关，因此有必要在不同程度上依赖主观判断。自20世纪50年代以来，人们一直在探索和量化主观判断的方法，但很少应用于环境暴露评估领域。在该项目的这一阶段，通过同行提名程序选出了7名苯暴露评估专家，参加了为期2天的研讨会，并接受了单独采访，以了解他们对住宅环境、住宅室内和个人空气分布的判断苯浓度（6天的综合平均值）的非吸烟，非职业暴露的目标和研究人群的美国环保署区域V试点研究。具体而言，要求每位专家以概率形式描述这些分布的算术平均值和第90次幂。本文介绍了专家对目标人群接触苯浓度的判断。专家们对个人空气中苯含量的判断是对其他分布判断中观察到的模式的示范。他们对平均值的预测最接近一致;除了一个例外，他们对平均值的最佳估计值落在7-11微克/立方米之间，尽管他们在所表示的不确定程度上表现出惊人的差异。他们对第90百分位数的估计差异更大，除一名专家外，所有专家的最佳估计值范围为12至26微克/立方米。然而，他们对第90百分位数的预测更加不确定。本文表明，连贯的主观判断，可以从暴露评估科学家和批判性地探讨主观判断方法的挑战和潜在的好处。该项目第二阶段的结果将在第二篇论文中介绍，在该阶段，NHEXAS在V区实地研究的测量结果用于校准专家对研究人群苯暴露的判断。
This paper presents the results of the first phase of a study, conducted as an element of the National Human Exposure Assessment Survey (NHEXAS), to demonstrate the use of expert subjective judgment elicitation techniques to characterize the magnitude of and uncertainty in environmental exposure to benzene. In decisions about the value of exposure research or of regulatory controls, the characterization of uncertainty can play an influential role. Classical methods for characterizing uncertainty may be sufficient when adequate amounts of relevant data are available. Frequently, however, data are neither abundant nor directly relevant, making it necessary to rely to varying degrees on subjective judgment. Since the 1950s, methods to elicit and quantify subjective judgments have been explored but have rarely been applied to the field of environmental exposure assessment. In this phase of the project, seven experts in benzene exposure assessment were selected through a peer nomination process, participated in a 2-day workshop, and were interviewed individually to elicit their judgments about the distributions of residential ambient, residential indoor, and personal air benzene concentrations (6-day integrated average) experienced by both the non-smoking, non-occupationally exposed target and study populations of the US EPA Region V pilot study. Specifically, each expert was asked to characterize, in probabilistic form, the arithmetic means and the 90th percentiles of these distributions. This paper presents the experts' judgments about the concentrations of benzene encountered by the target population. The experts' judgments about levels of benzene in personal air were demonstrative of patterns observed in the judgments about the other distributions. They were in closest agreement about their predictions of the mean; with one exception, their best estimates of the mean fell within 7–11 μg/m 3 although they exhibited striking differences in the degree of uncertainty expressed. Their estimates of the 90th percentile were more varied with the best estimates ranging from 12 to 26 μg/m 3 for all but one expert. However, their predictions of the 90th percentile were far more uncertain. The paper demonstrates that coherent subjective judgments can be elicited from exposure assessment scientists and critically examines the challenges and potential benefits of a subjective judgment approach. The results of the second phase of the project, in which measurements from the NHEXAS field study in Region V are used to calibrate the experts' judgments about the benzene exposures in the study population, will be presented in a second paper.