Objectives: The aim of this study was to investigate doctors' knowledge of the relative and absolute costs of diagnostic tests, medical consumables (e.g., syringes or intravenous tubing), and healthcare visits as well as to determine factors influencing awareness.
Methods: For this systematic review, we searched the Cochrane Library, EconoLit, EMBASE, and MEDLINE; reviewed reference lists; and had contact with authors. Studies were included if either doctors or trainees were surveyed, there were >10 survey respondents, costs of diagnostic or therapeutic items were estimated, results were expressed quantitatively, and a clear description was provided of how authors defined Accurate Estimates and determined True Cost. Two authors reviewed each article for eligibility and extracted data independently. Cost accuracy outcomes were summarized, but data were not combined due to extensive heterogeneity.
Results: Fourteen articles were included in the final analysis. Cost accuracy was low; 33 percent of estimates were within 20 percent or 25 percent of true cost and 50 percent were within 50 percent or in the 50-200 percent range of the true cost. Country, year of study, level of training, and specialty did not impact accuracy. The cost of items appears to have no impact on the accuracy (Fisher's exact test, p = .41) or pattern of estimation (binomial test, p = .92).
Conclusions: Doctors have a limited understanding of diagnostic and nondrug therapeutic costs, and we could not identify anything that impacts understanding of these costs. More focus is required in the education of physicians about costs and the access to cost information.