Texas A&M University, College Station, TX (LL, AJR, TRS)
Med Decis Making. 2012 May-Jun;32(3):488-97. doi: 10.1177/0272989X11427958. Epub 2011 Nov 18.
In addition to incurring direct treatment costs and generating direct health benefits that improve longevity and/or health-related quality of life, medical interventions often have further or "unrelated" financial and health impacts, raising the issue of what costs and effects should be included in calculating the cost-effectiveness ratio of an intervention. The "consistency principle" in medical cost-effectiveness analysis (CEA) requires that one include both the cost and the utility benefit of a change (in medical expenditures, consumption, or leisure) caused by an intervention or neither of them. By distinguishing between exogenous changes directly brought about by an intervention and endogenous patient responses to the exogenous changes, and within a lifetime utility maximization framework, this article addresses 2 questions related to the consistency principle: 1) how to choose among alternative internally consistent exclusion/inclusion rules, and 2) what to do with survival consumption costs and earnings. It finds that, for an endogenous change, excluding or including both the cost and the utility benefit of the change does not alter cost-effectiveness results. Further, in agreement with the consistency principle, welfare maximization implies that consumption costs and earnings during the extended life directly caused by an intervention should be included in CEA.
除了产生直接的治疗成本并带来直接的健康效益，延长寿命和/或提高与健康相关的生活质量外，医疗干预通常还会产生进一步的或“不相关的”财务和健康影响，这就提出了一个问题，即计算干预措施的成本效益比时，应该包括哪些成本和效果。医疗成本效益分析（CEA）中的“一致性原则”要求，对于干预措施引起的变化（在医疗支出、消费或休闲方面），要么同时包括成本和效用收益，要么都不包括。本文通过区分干预措施直接带来的外生变化和患者对外生变化的内生反应，并在终生效用最大化框架内，解决了与一致性原则相关的两个问题：1）如何在替代的内部一致性排除/包含规则之间进行选择，以及 2）如何处理生存消费成本和收益。研究结果表明，对于内生变化，排除或包含变化的成本和效用收益都不会改变成本效益结果。此外，与一致性原则一致，福利最大化意味着应将干预措施直接导致的延长寿命期间的消费成本和收益纳入 CEA 中。
