Evaluation of diagnostic technologies background, challenges, methods

Research area: HTA-methods & steering instruments

Duration: November 2009 - August 2010

Project co-operation: Ingrid Zechmeister
Suggested by: HVB
Publication: HTA Project reoprt No. 36 - https://eprints.aihta.at/898

Background
Diagnostic technologies are used to confirm or exclude the presence of disease or to classify disease. Ultimately, test results should impact on diagnostic or therapeutic decisions, finally resulting in improved patient-relevant outcomes.

For reasons that diagnostic tests can also be associated with adverse consequences, and uncritical use has led to a considerable impact on expenditures for health care, the identification of efficient and effective technologies is crucial. In order to ensure a reasonable allocation of resources, evidence-based principles, as for the evaluation of interventions, have to be applied.  In the HTA context, where diagnostics are assessed beyond their mere efficacy taking the most important consequences for patients and for health systems into account, unique methodological challenges occur.

Aims

To give an overview of specific methodological challenges associated with the evaluation of diagnostic technologies.To describe the methodologies used by selected institutions for the assessment of diagnostic technologies.Based on these findings, to develop a potential method for the evaluation of diagnostic technologies relevant to stakeholders.

Research questions

• Which parameters are used to describe diagnostic test accuracy (e.g. sensitivity, specificity, positive predictive value, pre-test probability)?
• On which levels can the effectiveness of diagnostic tests be evaluated (e.g. test accuracy, patient relevant outcomes, implications for the health system)?
• Which methodological challenges are associated with the evidence-based evaluation of the clinical effectiveness of a diagnostic test (appraising studies of diagnostic tests, linked evidence, missing reference tests)?
• Which methods are used by selected institutions to evaluate diagnostic technologies; is there a common pattern which allows the drawing of a general valid approach relevant to decision-makers?

Methods
Unsystematic hand-searches (manuals, guidelines, of selected institutions, Scopus, reference lists of relevant publications) and systematic literature searches of electronic databases (MEDLINE, EMBASE, HTA- database) using Boolean operators, MESH terms (e.g. “diagnostics”, “evidence-based medicine”) and free text search (e.g. “diagnostic test”, “methodology”, “evaluation”) to identify problems and methods used for the evaluation of diagnostic technologies.

Categorization of the identified challenges and the description of relevant methodological approaches of the selected institutions. Analysis and synthesis of these approaches to determine a method relevant to health systems.