Data from: Screening of health care workers for tuberculosis: development and validation of a new health economic model to inform practice

BACKGROUND: Methods for determining cost-effectiveness of different treatments are well established, unlike appraisal of non-drug interventions, including novel diagnostics and biomarkers. OBJECTIVE: We develop and validate a new health economic model by comparing cost-effectiveness of tuberculin skin test, TST; blood test, IGRA; and TST followed by IGRA in conditional sequence, in screening health care workers for latent or active TB. DESIGN: We focus on healthy life years gained as the benefit metric, rather than quality adjusted life years (QALYs) given limited data to estimate quality-adjustments of life years with TB and complications of treatment, like hepatitis. Healthy life years gained refers to the number of TB or hepatitis cases avoided, and the increase in life expectancy. We incorporate disease and test parameters informed by systematic meta-analyses and clinical practice. Health and economic outcomes of each strategy are modelled as a decision tree in Markov chains, representing different health states informed by epidemiology. Cost and effectiveness values are generated as the individual is cycled through 20 years of the model. Key parameters undergo one-way and Monte Carlo probabilistic sensitivity analyses. SETTING: Screening health care workers in secondary and tertiary care. RESULTS: IGRA is the most effective strategy, with incremental costs per healthy life year gained of £10,614 - £20,929, base case, £8,021 - £18,348, market costs TST £45, IGRA £90, IGRA specificities of 99% - 97%; mean (5%, 95%), £12,060 (£4,137 - £38,418) by Monte Carlo analysis. CONCLUSIONS: Incremental costs per healthy life year gained, a conservative estimate of benefit, are comparable to the £20,000 - £30,000 NICE band for IGRA alone, across wide differences in disease and test parameters. Health gains justify IGRA costs, even if IGRA tests cost three times TST. This health economic model offers a powerful tool for appraising non-drug interventions in the market and under development.研究背景：相较于新型诊断技术与生物标志物等非药物干预措施的评估，不同治疗方案的成本效益分析方法已较为成熟。 研究目标：本研究通过对比结核菌素皮肤试验（Tuberculin skin test, TST）、干扰素γ释放试验（Interferon-gamma release assay, IGRA）以及序贯先TST后IGRA的三种筛查策略，在医护人员潜伏性或活动性肺结核（Tuberculosis, TB）筛查中的成本效益，以此开发并验证一款全新的卫生经济学模型。 研究设计：鉴于目前针对肺结核患者与治疗并发症（如肝炎）的生命质量调整系数的相关数据有限，本研究以健康获益年数（healthy life years gained）作为效益衡量指标，而非质量调整生命年（quality adjusted life years, QALYs）。健康获益年数指可避免的肺结核或肝炎病例数，以及由此带来的预期寿命增长。本研究纳入经系统Meta分析与临床实践验证的疾病与检测相关参数。各筛查策略的健康与经济结局通过马尔可夫链决策树模型模拟，该模型以流行病学数据为基础划分不同健康状态。研究对象在模型中循环模拟20年，以此生成对应成本与效益数值。针对核心参数开展单因素敏感性分析与蒙特卡洛概率敏感性分析。 研究场景：二级与三级医疗机构内的医护人员肺结核筛查工作。 研究结果：IGRA为三种策略中效益最优的方案。基准情景下，每获得1个健康获益年数的增量成本为10614~20929英镑；参考市场定价（TST单次45英镑、IGRA单次90英镑，IGRA特异度99%~97%）时，每健康获益年数的增量成本为8021~18348英镑。经蒙特卡洛分析后，平均增量成本为12060英镑（95%置信区间：4137~38418英镑）。 研究结论：作为保守的效益估算方式，每健康获益年数的增量成本与英国国家卫生与临床优化研究所（National Institute for Health and Care Excellence, NICE）推荐的单采用IGRA时20000~30000英镑的成本阈值区间相当，且该结果不受疾病与检测参数的大范围波动影响。即便IGRA检测成本为TST的3倍，其带来的健康获益仍足以覆盖对应检测成本。本研究开发的卫生经济学模型可为市场中及在研的非药物干预措施提供强有力的评估工具。