B. Key Attributes of Cost Analyses 成本分析的关键属性

在成本分析中，考虑成本和成果的方法在许多重要方面可能有所不同，例如比较器的选择，经济分析的角度和分析的时间范围。表格5-3是这些属性的基础“清单”，其中一些属性在下面有简短描述。这些属性应被慎重考虑，参与者应有负责设计和成本分析的调查员，审查或评估这些分析报告的评估人员以及打算利用这些分析结果的决策者。考虑到成本和成果的不同衡量方法，所有研究都应该在这些方面阐明其方法。

表格5-3.设计和审查成本分析时要考虑的属性

• 比较器
• 视角
• 成果/终点的选择
• 效能与效率的权衡
• 数据采集方法
• 直接成本（医疗保健和其他）
• 间接成本（例如生产力损失）
• 实际成本与费用/价格的权衡
• 边际成本与平均成本的权衡
• 时间跨度分析
• 折扣
• 通货膨胀的调整空间
• 使用的模型
• 敏感性分析
• 报告结果
• 资金来源

比较器：任意两项干预措施之间的成本分析比较都必须说明比较器。这可能是护理标准（当前最佳做法），最低限度练习或无干预。有分析表明良好的新干预措施选择的比较器，有的已经不再适用于实践中，有的是次标准护理，有的不适合目标患者人群。

视角：成本分析的视角是指控制成本，实现产出的立足点。例如，可以从很多角度出发：整个社会，第三方付款人，医生，医院或病人。显然，从不同角度来看，成本和产出的实现方式都是不一样的。许多分析师倾向于从整个社会的宏观角度出发，从而确定相应成本和产出。然而，“社会”本身可能不是决策者，从决策者角度看，其成本效益可能与卫生部，保险公司，医院经理，患者或其他决策者的成本效益不同。如果政府确实承担（或者代表相关利益方）所有社会层面的成本和产出，那么这个观点可能类似于国家或地区政府的观点。

直接成本。Direct costs represent the value of all goods, services, and other resources consumed in providing health care or dealing with side effects or other current and future consequences of health care.在提供医疗保健、处理副作用或其他当前和将来的医疗保健后果方面，所消耗的所有商品，服务和其他资源的价值总和就是直接成本。Two types of direct costs are direct health care costs and direct non-health care costs.直接成本有两种类型：直接医疗保健费用和直接非保健费用。

Direct health care costs include costs of physician services, hospital services, drugs, etc. 直接医疗费用包括医师服务费，医院服务费，药品费等。involved in delivery of health care. 包括医疗护理的实施。Direct non-health care costs are incurred in connection with health care, such as for care provided by family members and transportation to and from the site of care. 直接的非医疗保健费用是与医疗保健有关的，例如家庭成员提供的护理，以及往返护理场所的交通费用。In quantifying direct health care costs, many analyses use readily available hospital or physician charges (i.e., taken from price lists) rather than true costs, whose determination may require special analyses of resource consumption. 在量化直接医疗保健费用时，许多分析使用简单易查的医院或医生费用（即从价格表中取得），而不是真实成本。确定真实成本其确定可能需要对资源消耗进行特殊分析。Charges (as well as actual payments) tend to reflect provider cost-shifting and other factors that decrease the validity of using charges to represent the true costs of providing care.收费（以及实际付款）往往反映出提供商的费用转移，以及其他降低使用费用有效性的因素，以代表提供医疗服务的真实成本。

间接费用:Analyses should account for indirect costs, sometimes known as “productivity losses.” These include the costs of lost work due to absenteeism or early retirement, impaired productivity at work (sometimes known as “presenteeism”), and lost or impaired leisure activity. 间接成本应被考虑进去，有时它被称为“生产力损失”，其中包括由于旷工或提前退休而导致的工作损失，工作生产力下降（有时称为“出勤”）以及失去或受损的休闲活动。Indirect costs also include the costs of premature mortality. 间接成本还包括退休前死亡的成本。Intangible costs of pain, suffering, and grief are real, yet very difficult to measure and are often omitted from cost analyses.痛苦和悲伤地隐形成本也是真实存在的，但难以测量，并且经常在成本分析中被省略。

Time horizon. 时间跨度分析Interpretation of cost analyses must consider that the time horizon (or time-frame) of a study is likely to affect the findings regarding the relative magnitudes of costs and outcomes of a health care intervention. 成本分析的解释必须考虑研究的时间范围可能影响到一些结果，这些结果往往关系到成本和医疗保健干预结果的相对大小。Costs and outcomes associated with a particular intervention usually do not accrue in steady streams over time. 与特定干预相关的成本和成果通常不会随着时间的流逝而自然增长。如在表格5-4 中所提出的，大部分因投资健康项目而获利的健康收益在成功之前都需要数年的产出。任何关于某个健康项目的分析成本效益都可能随时间跨度而变化（比如在项目开始后的5,10,15,20年）。The meaningful time horizons for assessing the cost effectiveness of, e.g., emergency appendectomies, cholesterol-lowering in high-risk adults, and smoking prevention in teenagers are likely to be quite different. 用于评估成本效益的有效时间跨度很可能是不同的，比如紧急阑尾切除术，高危成人胆固醇降低和青少年吸烟预防。For example, an analysis conducted for the Medicare program in the US to determine cost and time tradeoffs of hemodialysis and kidney transplantation showed that the annualized expenditure by the Medicare End-Stage Renal Disease Program for a dialysis patient was $32,000. 例如，有一项针对美国医疗保险项目进行的分析，致力于判定如何在血液透析和肾移植的成本和时间中找到平衡。这项分析发现，透析患者的医疗终期肾脏疾病计划的年度支出为32,000美元。Although patients with functioning transplanted kidneys required a first-year expenditure of $56,000, they cost Medicare only an average of $6,400 in succeeding years. 虽然肾移植患者需要在第一年支付56,000美元，但在接下来的几年里，他们的平均医疗费用只有6,400美元。On average, estimated cumulative dialysis and transplantation costs reached a break-even point in about three years, after which transplantation provided a net financial gain compared to dialysis, according to the analysis (Rettig 1991).平均来说，根据上述分析，预计总透析和移植费用可以在三年内达到收支平衡，在此之后，相比透析而言，移植会产生净收入。

表格5-4.Time Horizon of Economic Analysis 经济分析的时间跨度

Determination of cost effectiveness can depend on relative accruals of costs and health benefits at selected time horizon of analysis. 成本效益的确定可以取决于特定分析时间范围内，成本和健康收益的相对自然增长额。Here, improvements in population health lag behind (are delayed relative to) costs. 在这方面，人口健康状况的改善落后于成本。What is an appropriate time to conduct a cost-effectiveness analysis?进行成本效益分析的适当时机是什么？

Time horizons should be long enough to capture streams of health and economic outcomes (including significant intended and unintended ones). 时间范围应该足够长，以捕捉健康和经济产出的活动（包括预期和非预期的）。These could encompass a disease episode, patient life, or even multiple generations of life (such as for interventions in women of child-bearing age or interventions that may cause heritable genetic changes). 这些可能包括疾病发作，患者生命甚至多代人的生命（例如对生育年龄的妇女进行干预或可能导致遗传变异的干预措施）。Quantitative modeling approaches may be needed to estimate costs and outcomes that are beyond those of available data. 可能需要定量建模方法来估算超出可用数据的成本和结果。Of course, the higher the discount rate used in an analysis, the less important are future outcomes and costs.当然，分析中使用的贴现率越高，未来的成果和成本就越不重要。

Average costs vs. marginal costs. 平均成本与边际成本。Assessments should make clear whether average costs or marginal costs are being used in the analysis. 评估应明确平均成本或边际成本是否出现在分析中。Whereas average cost analysis considers the total (or absolute) costs and outcomes of an intervention, marginal cost analysis considers how outcomes change with changes in costs (e.g., relative to the standard of care or another comparator), which may provide more information about how to use resources efficiently. 虽然平均成本分析考虑了干预的总体（或绝对）成本和产出，边际成本分析仍然考虑了结果随着成本如何变化（例如，相对于护理标准或另一个比较器）。这可能指导我们更有效地利用资源。Marginal cost analysis may reveal that, beyond a certain level of spending, the additional benefits are no longer worth the additional costs. 边际成本分析可能表明，额外收益不值得追加成本。For example, the average cost per desired outcome of a protocol of iterative screening tests may appear to be quite acceptable (e.g., $2,451 per case of colorectal cancer detected assuming a total of six tests per person), whereas marginal cost analysis demonstrates that the cost of adding the last test (i.e., the additional cost of the sixth test per person) to detect another case of cancer would be astronomical.例如，如表格5-5所示，迭代筛查试验的各期望结果的平均成本似乎是相当不错的（例如，假设每个人进行六次测试，每检测到一次结直肠癌，就需要2,451美元），而边际成本分析表明，再增加一次测试的成本（即，每人的第六次测试以外的成本）来检测另一种癌症的价格将是极为昂贵的。

Discounting贴现.Cost analyses should account for the effect of the passage of time on the value of costs and outcomes. 成本分析应考虑到时间的流逝对成本和产出的价值影响。Costs and outcomes that occur in the future usually have less present value than costs and outcomes realized today. 未来的成本和产出通常会少于比当前的成本和产出。Discounting reflects the time preference for benefits earlier rather than later; it also reflects the opportunity costs of capital, i.e., whatever returns on investment that could have been gained if resources had been invested elsewhere. 贴现反映了时间偏好早期利益而非晚期利益；它还反映了资本的机会成本，即如果把资源在其他地方投资，可能会获得的投资回报。Thus, costs and outcomes should be discounted relative to their present value (e.g., at a rate of 3% or 5% per year). 因此，成本和产出应相对于其现值予以贴现（例如，以每年3％或5％的比例）。Discounting allows comparisons involving costs and benefits that flow differently over time. 贴现允许比较随时间变化的成本和收益。It is less relevant for “pay-as-you-go” benefits, such as if all costs and benefits are realized together within the same year. 它与“现收现付”的福利关联度很小，例如，如果在同一年内达到所有成本和收益。It is more relevant in instances where these do not occur in parallel, such as when most costs are realized early and most benefits are realized in later years.当它们不同时出现时，相关性更高。比如说，当大部分成本都在早期投入，而大部分收益则在后期获得。Discount rates used in cost analyses are typically based on interest rates of government bonds or the market interest rates for the cost of capital whose maturity is about the same as the duration of the effective time horizon of the health care intervention being evaluated. 成本分析中使用的折现率通常基于政府债券的利率或资本成本的市场利率，其成熟度与正在评估的医疗保健干预措施的有效期限一致。shows the basic formula for calculating present values for a given discount rate, as well as how the present value of a cost or benefit that is discounted at selected rates changes over time.表格5-6显示了给定折现率计算当前值的基本公式，以及按选定费率折扣的成本或收益的现值如何随时间而变化。

Cost analyses should also correct for the effects of inflation (which is different from the time preference accounted for by discounting), such as when cost or cost-effectiveness for one year is compared to another year.成本分析还应纠正通货膨胀的影响（与折扣所占的时间偏差不同），例如比较不同年份的成本或成本效益。

Sensitivity analysis敏感度分析.Any estimate of costs, outcomes, and other variables used in a cost analysis is subject to some uncertainty. 在成本分析中，使用的任何成本、产出和其他变量的估计值都是不确定的。Therefore, sensitivity analysis should be performed to determine if plausible variations in the estimates of certain variables thought to be subject to significant uncertainty affect the results of the cost analysis. 因此，应进行敏感度分析，以确定某些显著不确定的变量，其估计值的合理变化范围是否英雄成本反洗的结果。A sensitivity analysis may reveal, for example, that including indirect costs, or assuming the use of generic as opposed to brand name drugs in a medical therapy, or using a plausible higher discount rate in an analysis changes the cost-effectiveness of one intervention compared to another.敏感度分析可能会揭示，例如，包括间接成本，或假定在药物治疗中使用通用而不是品牌药物，或在分析中使用合理的较高贴现率，可以改变某干预相对于其他干预的成本效益。

表格5-5：Average Cost Analysis vs. 平均成本分析与边际成本分析的比较Marginal Cost Analysis

The importance of determining marginal costs is apparent in this analysis of a proposed protocol of sequential stool guaiac testing for colon cancer. 在分析结肠癌顺序粪便愈伤组织测试方案的过程中，确定边际成本的重要性是显而易见的。Here, average cost figures obscure a steep rise in marginal costs of testing because the high detection rate from the initial tests is averaged over subsequent tests that contribute little to the detection rate. 在这里，平均成本数据模糊了边际成本的急剧升高。因为从初始测试获得的高检测值是取了后续不影响检测值测试的平均值。This type of analysis helps to demonstrate how it is possible to spend steeply increasing health care resources for diminishing returns in health benefits.这种分析有助于证明通过花费大量递增的医疗保健资源来减少健康福利的回报是可能发生的。

Cancer screening and detection costs with sequential guaiac tests 癌症筛查和连续测试的测试成本

This analysis assumed that there were 72 true cancer cases per 10,000 population. 该分析假设每10,000人有72个真正的癌症病例。The testing protocol provided six stool guaiac tests per person to detect colon cancer. 测试方案给每人提供六次粪便测试以检测结肠癌。If any one of the six tests was positive, a barium-enema test was performed, which was assumed to yield no false-positive and no false-negative results. 如果六项测试中有任意一次结果为阳性，则进行钡灌肠试验。假设该实验不产生假阳性或无假阴性结果。Other assumptions: the true-positive cancer detection rate of any single guaiac test was 91.667%; the false-positive rate of any single guaiac test was 36.508%; the cost of the first stool guaiac test was $4 and each subsequent guaiac test was $1; the cost of a barium-enema was $100. 其他假设：任何单次粪便实验的真阳性癌症检出率为91.667％；任何单次试验的假阳性率为36.508％；第一次粪便测试的费用为4美元，随后每次测试花费1美元；钡灌肠的成本为100美元。The marginal cost per case detected depends on the population screened and the sensitivity of the test used.每次检测的边际成本取决于筛查人群和测试使用的敏感度标准。

From: N Engl J Med, Neuhauser D, Lewicki AM. What do we gain from the sixth stool guaiac? 293:226-8. Copyright © 1975 Massachusetts Medical Society. Reprinted with permission from Massachusetts Medical Society.

While cost analysis methods are generally becoming more harmonized, considerable variation in their use remains. 虽然成本分析方法总体来说变得更加统一，但仍然存在相当大的变化。Although some variation is unavoidable, some differences in economic perspective, accounting for direct and indirect costs, time horizon, discounting and other aspects are arbitrary, result from lack of expertise, and may reflect biases on the part of investigators or study sponsors 虽然一些变化是不可避免的，因为缺乏专业知识，经济角度的差异、直接和间接成本、时间范围、贴现等方面的因素是随机的。这可能反映了部分调查者或研究发起人的偏见。(Elixhauser 1998; Hjelmgren 2001; Nixon 2000).Guidelines and related standards for conducting costs analyses in HTA have evolved, especially since the 1990s, helping to improve their quality, reporting, and interpretation of their findings特别是自20世纪90年代以来，HTA进行成本分析的指导原则和相关标准已经改变，从而提高其质量，报告和解释结果 (Byford 1998; Drummond 2005; Eccles 2001; Gold 1996; Husereau 2013; Mauskopf 2007; McGhan 2009; Weinstein 1977).Also, HTA agencies and collaborations are increasingly transparent about their methods involving economic analyses 此外，HTA机构和合作方对于涉及经济分析的方法也越来越透明(IQWiG 2009; Wonderling 2011).

Box V-6. 表格5-6：Discount Rate Calculation and Use inDetermining Present Value of Future Costs and Benefits 贴现率计算和使用确定未来成本和收益的现值

Discount rate calculation: compiling the discounted stream of costs (or benefits)贴现率计算：整合随时间变化的贴现成本流（或收益流）

over time:

    P = present value        F = future cost (or benefits) at year n        r = annual discount rate

Present value (P) of future cost (F) occurring at year n at selected annual discount rate (r):以年度折扣率（r）计算的第n年发生的未来成本（F）的现值（P）：

Discount Rate贴现率

• For example, the present value of a cost (or benefit) of $1,000 occurring:例如，1,000美元的成本（或收益）的现值出现在：
  • 1 year in the future, using 10% discount rate, is $910未来1年，使用10％的折扣率，为910美元
  • 5 years in the future, using 3% discount rate, is $860未来5年，使用3％的折扣率，为$ 860
  • 50 years in the future, using 5% discount rate, is $90未来50年，使用5％的折扣率，是90美元