For nearly three decades, international comparisons of population health have been informed by the project known as the Global Burden of Disease Study (GBD). Growing steadily in scope and sophistication as its headquarters moved from Harvard to the World Health Organization and then to the University of Washington, the GBD has become a massive statistical enterprise, taking in raw data on disease and impairment and issuing influential analytical reports on national and international priorities for health policy and resource allocation. The effort to bring order to such a complex area inevitably invites debate and generates controversy. Contention arises not only over resolving inherent problems of commensurability but also on underlying concepts and ethical premises. The present volume, one in an Oxford series called Population-Level Bioethics, is a collection of essays on these matters—mostly by GBD defenders, a few by critics.

An introductory chapter by the five editors (Nir Eyal, Samia A. Hurst, Christopher J. L. Murray, S. Andrew Schroeder, and Daniel Wikler) poses the main questions and relates them to past work. Subsequent chapters are grouped into sections on measuring health, causal attribution of disability and death, discounting (for time and uncertainty) and age-weighting of life-years lost, and GBD's use in priority setting. On measuring health, the first of these, the fundamental disagreement is between evaluative and naturalistic conceptions—whether health should be seen as a dimension of well-being, gauged by inquiries about health-related quality of life, or as describing an individual's overall functional efficiency. Joshua A. Salomon supports the former position, which is that of the GBD with its elaborate pursuit of disability weights and calculations of DALYs and QALYs. Daniel M. Haussman and later Elselijn Kingma dissent, favoring a function-based approach. The GBD exercise, they aver, despite its claims, is a measurement of the value of health, not of the amount of health: “there is no such thing as the quantity of health.” The chapters on causation draw on literature in philosophy and even game theory (Shapely values) to complicate the familiar treatment of the cause of death in epidemiology and demography. Causal attribution is mostly impossible, Ned Hall concludes, unhelpfully for the GBD. “Sometimes—rarely, but not never—we encounter additive causal structures. And when we do, the notion of causal contribution has a useful role to play in describing what we have found. But most of the time we do not, and it does not.” On time discounting, contributors endorse the rejection of the practice in the current GBD. So too with age-weighting, an especially contentious choice in earlier versions: a year of healthy life is now taken to have the same value in infancy as in early or even late adulthood. (Stillbirths count for nothing.)

Burden-of-disease calculations are seen as a guide for health policy decisions, but their use is not straightforward. Fairness becomes an issue, although often in practice overridden by economics and politics. But if an ethical goal is sought, should it be an equitable allocation of health, healthcare, or alleviated suffering? Is individual responsibility—blameworthiness—to be taken into account? Should trade-offs between health and other dimensions of well-being be considered, which would necessarily affect distributional judgments? For example, one contributor suggests “years of good life,” covering consumption as well as health, as an alternative to QALYs in resource allocation. Although various chapters include recommendations for further investigation, the effort may run into diminishing returns. The reader of this volume, I would guess, is not likely to be persuaded that continued refinement of the conceptual foundations of priority setting in population health is a convergent path, headed toward, if never attaining, some pure measurement protocol. —G.McN.

近三十年来，全球疾病负担研究 (GBD) 项目为人口健康的国际比较提供了信息。随着总部从哈佛搬到世界卫生组织再到华盛顿大学，GBD 的范围和复杂性稳步增长，已经成为一个庞大的统计企业，接收有关疾病和损伤的原始数据，并发布有关国家和地区的有影响力的分析报告。卫生政策和资源分配的国际优先事项。为这样一个复杂领域带来秩序的努力不可避免地会引发争论和争议。争论不仅出现在解决可通约性的固有问题上，而且还出现在基本概念和道德前提上。本卷是牛津系列丛书中的一卷，名为《人口水平生物伦理学》，

五位编辑（Nir Eyal、Samia A. Hurst、Christopher JL Murray、S. Andrew Schroeder 和 Daniel Wikler）的介绍性章节提出了主要问题并将它们与过去的工作联系起来。随后的章节分为以下几节：衡量健康、残疾和死亡的因果归因、折现（针对时间和不确定性）和损失生命年的年龄加权，以及 GBD 在优先级设置中的使用。在衡量健康方面，首先，根本分歧在于评价性概念和自然主义概念之间的分歧——健康是应该被视为幸福的一个维度，通过对与健康相关的生活质量的调查来衡量，还是描述个人的整体功能效率。Joshua A. Salomon 支持前任，这就是 GBD 对残疾权重和 DALYs 和 QALYs 计算的精心追求。Daniel M. Haussman 和后来的 Elselijn Kingma 持不同意见，赞成基于函数的方法。他们声称，尽管 GBD 运动有其声称，但它衡量的是健康的价值，而不是健康的数量：“没有健康数量这样的东西。” 关于因果关系的章节借鉴了哲学文献甚至博弈论（Shapely 价值观），使流行病学和人口学中对死因的熟悉处理变得复杂。Ned Hall 总结说，因果归因几乎是不可能的，这对 GBD 没有帮助。“ 不是健康的数量：“没有健康数量这样的东西。” 关于因果关系的章节借鉴了哲学文献甚至博弈论（Shapely 价值观），使流行病学和人口学中对死因的熟悉处理变得复杂。Ned Hall 总结说，因果归因几乎是不可能的，这对 GBD 没有帮助。“ 不是健康的数量：“没有健康数量这样的东西。” 关于因果关系的章节借鉴了哲学文献甚至博弈论（Shapely 价值观），使流行病学和人口学中对死因的熟悉处理变得复杂。Ned Hall 总结说，因果归因几乎是不可能的，这对 GBD 没有帮助。“有时——很少，但并非从来没有——我们会遇到附加的因果结构。当我们这样做时，因果贡献的概念在描述我们发现的内容方面可以发挥有用的作用。但大多数时候我们没有，而且也没有。” 在时间折扣方面，贡献者赞同拒绝当前 GBD 中的做法。年龄加权也是如此，在早期版本中，这是一个特别有争议的选择：现在，一年的健康生活被认为在婴儿期与成年早期甚至晚期具有相同的价值。（死胎算不了什么。）

疾病负担计算被视为卫生政策决策的指南，但它们的使用并不简单。公平成为一个问题，尽管在实践中经常被经济和政治所取代。但是，如果寻求道德目标，它应该是健康、医疗保健或减轻痛苦的公平分配吗？是否应考虑个人责任——应受指责性？是否应该考虑健康与福祉其他维度之间的权衡，这必然会影响分配判断？例如，一位撰稿人建议“多年的美好生活”，涵盖消费和健康，作为资源分配中 QALY 的替代方案。尽管各个章节都包含对进一步调查的建议，但这些努力可能会遇到收益递减的情况。这本书的读者，我猜，不太可能被说服继续完善人口健康优先事项设定的概念基础是一条趋同的道路，朝着一些纯粹的测量协议迈进，如果永远不会实现。——G.McN