Medical Statistics Unit, London School of Hygiene and Tropical Medicine, London, UK.
Health Econ. 2011 Jul;20(7):842-52. doi: 10.1002/hec.1648. Epub 2010 Aug 26.
Cost-effectiveness analysis is usually based on life-years gained estimated from all-cause mortality. When an intervention affects only a few causes of death accounting for a small fraction of all deaths, this approach may lack precision. We develop a novel technique for cost-effectiveness analysis when life-years gained are estimated from cause-specific mortality, allowing for competing causes of death. In the context of randomised trial data, we adjust for other-cause mortality combined across randomised groups. This method yields a greater precision than analysis based on total mortality, and we show application to life-years gained, quality-adjusted life-years gained, incremental costs, and cost effectiveness. In multi-state health economic models, however, mortality from competing causes is commonly derived from national statistics and is assumed to be known and equal across intervention groups. In such models, our method based on cause-specific mortality and standard methods using total mortality give essentially identical estimates and precision. The methods are applied to a randomised trial and a health economic model, both of screening for abdominal aortic aneurysm. A gain in precision for cost-effectiveness estimates is clearly helpful for decision making, but it is important to ensure that 'cause-specific mortality' is defined to include all causes of death potentially affected by the intervention.
成本效益分析通常基于全因死亡率估计得出的生命年数。当干预措施仅影响少数几种导致死亡的原因，而这些原因只占所有死亡人数的一小部分时，这种方法可能缺乏准确性。我们开发了一种新的技术，用于从特定原因死亡率估计生命年数的成本效益分析，同时考虑了其他死亡原因。在随机试验数据的背景下，我们调整了跨随机组的其他原因死亡率。与基于总死亡率的分析相比，这种方法具有更高的精度，我们将其应用于生命年数、质量调整生命年数、增量成本和成本效益。然而，在多状态健康经济模型中，竞争原因的死亡率通常来自国家统计数据，并假定在干预组之间是已知且相等的。在这些模型中，我们基于特定原因死亡率的方法和使用总死亡率的标准方法给出了基本相同的估计值和精度。这些方法应用于腹部主动脉瘤的随机试验和健康经济模型。成本效益估计的精度提高显然有助于决策，但重要的是要确保“特定原因死亡率”的定义包括可能受到干预影响的所有死因。
