Figure 4 The best test strategy and expected utility depending on the prevalence of dentin caries (using utilities of dental students, and diagnostic accuracy from Table 1). Below the test threshold of 4% prevalence, the best strategy is to withhold treatment without taking a bitewing radiograph. Above the test–treatment threshold of 57% the best strategy is treatment also without resorting to testing. In the intermediate range of 4–57% the strategy maximizing health is testing and restoring surfaces with a positive test result