Townsend J, Buxton M, Harper G
Public and Environmental Health Research Unit, London School of Hygiene and Tropical Medicine, UK.
Health Technol Assess. 2003;7(20):iii, 1-82. doi: 10.3310/hta7200.
To develop a method of economic evaluation and triage for research prioritisation, before the funding decision.
Existing models were researched focusing on MEDLINE, HealthSTAR, IBSS and HEED.
Papers of primary relevance that included a proposed model were reviewed in detail, and their models appraised using criteria adapted from the EUR-ASSESS project and the authors' previous experience. From this the PATHS model was developed. It assumes three or more possible alternative outcomes or scenarios in terms of research results: 'favourable' to the technology being assessed, 'unfavourable' or 'inconclusive'. An associated flow of benefits or disbenefits, costs or savings is identified for each potential research outcome depending on the likely implementation of the results as judged by experts. These benefits and costs are weighted and discounted in the model to give an expected incremental cost-effectiveness ratio (EICER). EICERS could be estimated for any number of research areas or proposals to inform funding prioritisation. The model was tested and evaluated on three case studies identified in liaison with the NHS R&D HTA programme and the UK Medical Research Council. These case studies were funded research projects, where full evaluation was underway and where results would be reported during the PATHS project. The studies were selected to include surgery or other invasive procedures, and non-invasive health services projects (a fourth case study did not complete during the course of the study). The three case studies included randomised controlled trials of early surgery or observation for small abdominal aortic aneurysms, infusion protocols for adult pre-hospital care, and postnatal midwifery support.
Each of the three assessments indicated net clinical benefit or no clinical loss of benefit, in addition to health service cost savings in excess of the cost of the trial. For two case studies, the value of the proposed trial, as evaluated by the model in the prediction, was consistent with the ex post evaluation, thus providing positive tests of the value of the model. In the third case meaningful ex post analysis was not possible as very poor compliance with the trial protocol (indicated in the ex ante evaluation) seriously undermined its conclusions. During the study, at the request of the UK HTA programme, the model was also applied to a funding request for a large randomised trial of beta-interferon for multiple sclerosis treatment.
The PATHS model has a useful part to play in the research prioritisation process. Its strengths lie in its emphasis on the impact of research results on policy and practice (the keystone for NHS research) and net effects on health benefits and costs. It assesses the cost-effectiveness of the research and may identify ways to enhance the research design, endpoints relevant to implementation, analytical methods and dissemination. Further research is recommended to investigate the scope for synthesising the strengths of the PATHS model with other approaches including value of information; to compare ex ante and immediate ex post assessments of implementation with long term follow-up of actual implementation; and to assess the robustness of such approaches to the choice and number of experts used.
在做出资助决定之前，开发一种用于研究优先级排序的经济评估和筛选方法。
对现有模型进行了研究，重点关注MEDLINE、HealthSTAR、IBSS和HEED。
对包含拟议模型的主要相关论文进行了详细审查，并使用从EUR-ASSESS项目改编的标准以及作者以前的经验对其模型进行了评估。由此开发了PATHS模型。它假设就研究结果而言有三种或更多可能的替代结果或情景：对所评估技术“有利”、“不利”或“无定论”。根据专家判断的结果可能的实施情况，为每个潜在研究结果确定相关的收益或不利因素、成本或节省的流程。这些收益和成本在模型中进行加权和贴现，以得出预期增量成本效益比（EICER）。可以为任何数量的研究领域或提案估计EICER，以为资助优先级排序提供信息。该模型在与英国国家医疗服务体系研发卫生技术评估计划和英国医学研究理事会联络确定的三个案例研究中进行了测试和评估。这些案例研究是已资助的研究项目，正在进行全面评估，并且将在PATHS项目期间报告结果。这些研究的选择包括手术或其他侵入性程序以及非侵入性卫生服务项目（第四个案例研究在研究过程中未完成）。这三个案例研究包括小腹部主动脉瘤早期手术或观察的随机对照试验、成人院前护理的输液方案以及产后助产支持。
三项评估中的每一项都表明除了试验成本之外还有净临床益处或没有临床益处损失，以及卫生服务成本节省。对于两个案例研究，模型在预测中评估的拟议试验的价值与事后评估一致，从而对模型的价值进行了正面测试。在第三个案例中，由于对试验方案的依从性非常差（事前评估表明）严重破坏了其结论，因此无法进行有意义的事后分析。在研究期间，应英国卫生技术评估计划的要求，该模型还应用于一项关于β-干扰素治疗多发性硬化症的大型随机试验的资助申请。
PATHS模型在研究优先级排序过程中可以发挥有益作用。其优势在于强调研究结果对政策和实践的影响（英国国家医疗服务体系研究的关键）以及对健康益处和成本的净影响。它评估研究的成本效益，并可能确定加强研究设计、与实施相关的终点、分析方法和传播的方法。建议进一步研究以调查将PATHS模型的优势与其他方法（包括信息价值）相结合的范围；比较事前和即时事后对实施的评估与对实际实施的长期随访；并评估此类方法对所使用专家的选择和数量的稳健性。
