Background: Diagnostic test accuracy (DTA) systematic reviews are standard ways of summarising research evidence. DTA reviews may change clinical practice on an individual level, or their findings may be incorporated into guidelines to influence practice at the health service level. One factor that may affect a reviewás potential to influence clinical practice, and the way clinicians subsequently use tests, is how clearly the results are presented and how easy they are to interpret.

Objectives: To review available evidence regarding health professionalsá understanding of diagnostic information to inform decisions on how best to present the results of DTA reviews.

Methods: MEDLINE, EMBASE and PsycINFO were searched until March 2011, experts were contacted, citation searches of key papers were conducted, and reference lists were screened. Primary studies were included that reported on any outcomes relating to health professionalsá understanding of diagnostic test accuracy which was summarised as sensitivity, specificity, likelihood ratios, predictive values, accuracy or ROC curves. Due to the heterogeneity between studies in terms of design, health professionals, and measures of accuracy investigated, a narrative synthesis was used to combine results.

Results: To date 12 studies have been included; the review is ongoing. Initial results suggest that sensitivity and specificity are generally poorly understood by clinicians and are often confused with predictive values. Clinicians tend to overestimate the impact of a positive test result on the probability of disease and this overestimation increases with decreasing pre-test probabilities of disease. The most informative measures for clinicians may be estimates of the post-test probability of disease, which can be presented as a range corresponding to different pre-test probabilities.

Conclusions: Conclusions will inform recommendations for presenting estimates of test accuracy in DTA reviews.