Chapter 2: medical tests guidance (2) developing the topic and structuring systematic reviews of medical tests: utility of PICOTS, analytic frameworks, decision trees, and other frameworks

Abstract

Topic development and structuring a systematic review of diagnostic tests are complementary processes. The goals of a medical test review are to identify and synthesize evidence to evaluate the impacts alternative testing strategies on health outcomes and to promote informed decision making. A common challenge is that the request for a review may state the claim for the test ambiguously. Due to the indirect impact of medical tests on clinical outcomes, reviewers need to identify which intermediate outcomes link a medical test to improved clinical outcomes. In this paper, we propose the use of five principles to deal with challenges: the PICOTS typology (patient population, intervention, comparator, outcomes, timing, setting), analytic frameworks, simple decision trees, other organizing frameworks and rules for when diagnostic accuracy is sufficient.

Figure 1.

Application of USPSTF analytic framework to test evaluation. Adapted from Harris et al., 2001.

Figure 2.

Example of an analytical framework within an overarching conceptual framework in the evaluation of breast biopsy techniques. The numbers in the figure depict where the three key questions are located within the flow of the analytical framework.

Figure 3.

Replacement test example: full-field digital mammography versus screen-film mammography*. * Figure taken from Blue Cross and Blue Shield Association Technology Evaluation Center, 2002.

Figure 4.

Add-on test example: HER2 protein expression assay followed by HER2 gene amplification assay to select patients for HER2-targeted therapy*. Abbreviation: HER2 = human epidermal growth factor receptor 2. * Figure taken from Seidenfeld et al., 2008.

Figure 5.

Triage test example: positron emission tomography (PET) to decide whether to perform breast biopsy among patients with a palpable mass or abnormal mammogram*. * Figure taken from Samson et al., 2002.