Authors' objectives:

The Preliminary Assessment of Technology for Health Services (PATHS) study aimed to develop a method of economic evaluation and triage at the stage of research prioritisation, before the funding decision. It is for use either at the stage of deciding on an area of research for funding, or at the specific proposal stage, or both, and assesses whether the additional information from an assessment will justify its cost in terms of the likely health gain and costs resulting from its impact on the use of that technology, and if so what priority should be given to that assessment.

Authors' results and conclusions: Data for the model: The model is straightforward and transparent, and does not require major data collection. Data include estimates of benefits to patients, costs of the technology, level of its use in the absence of the proposed assessment (the counterfactual), likely developments in the technology during the period of evaluation, and expected changes in use of the technology given alternative outcomes of the assessment. Alternative values can be incorporated for net costs, benefits and probabilities for each scenario, and the expected level of the implementation can be adjusted, allowing the evaluation to reflect likely impact on practice as a result of reduction in uncertainty. Where available, empirical data are used, with gaps filled by expert opinion. The experts may include clinical, health economic and purchaser expertise to represent relevant decision-makers and to triangulate the estimates. Testing the model: The model was tested and evaluated on three case studies identified in liaison with the NHS R&D HTA programme and the MRC. These case studies were funded research projects, where full evaluation was underway and where results would be reported during the PATHS project. Two MRC- and two HTA-funded studies were selected to include surgery or other invasive procedures and non-invasive health services research projects; one case did not complete during the course of the study. The three case studies included randomised controlled trials of postnatal midwifery support, infusion protocols in adult pre-hospital care, and early surgery or observation for small abdominal aortic aneurysms. For two case studies, the value of the proposed trial, as evaluated by the model in the ex ante prediction, was consistent with the ex post evaluation, thus providing positive tests of the model. Each of these assessments indicated net clinical benefit or no clinical loss of benefits, in addition to health services cost savings in excess of the trial cost. In the third case meaningful ex post analysis was impossible, as very poor compliance with the trial protocol seriously undermined its conclusions. Live application of model: During the course of the project the investigators were asked to apply the model to an application for funding a large randomised trial of beta-interferon for multiple sclerosis treatment, submitted to the UK HTA programme. The results of this analysis illustrate further the use of the model.

Authors' recommendations: The NHS R&D programme sets relevance to the improvement of health and health services as the keystone for research prioritisation. To assess the effects on implementation the baseline level of use must be known, but this is rarely provided. Survey data may be considered an essential adjunct to a literature review, to provide a basis for assessing the relevance and potential importance of a health technology assessment, as information on the current use of a technology, and its expected trajectory, is essential to the assessment of payback. The implications are different for a new technology that would be adopted only if good evidence were provided, compared with a technology that, despite lack of good evidence, is already in use. A large part of the payback in the cases considered was due to an expectation that the research would lead to a reduction in the use of the technology were it proved to have low benefit. Negative results may produce high payback. An essential element of the evaluation is the explicit assessment of the counterfactual, and consideration of the length of time over which the research may influence policy. This will depend on emerging information and changes to the technology or its competitors. In an area of rapid technological change, the policy relevance of a piece of research may be transient. In conclusion, the PATHS model has a useful part to play in the research prioritisation process alongside existing criteria; its strength lies in its emphasis on impacts on policy and practice, 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, end-points, analytical methods and dissemination.

Authors' methods: Economic modelling

Project Status: Completed

URL for project: http://www.hta.ac.uk/971

Year Published: 2003

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: England, United Kingdom

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk

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