Personal view: 'don't ask, don't tell'--the undesirable consequences of incidental test results in gastroenterology.

A gastroenterologist is frequently approached to perform an endoscopic procedure after an incidental test has resulted in an unexpected positive finding. Should the incidental test result be ignored or automatically followed by an endoscopic procedure? The present analysis strives to characterize the common pattern of such scenarios and resolve their underlying dilemma. A model of game theory is used as a mathematical tool to develop general management strategies. Three clinical scenarios are used as examples to demonstrate this approach. The model is based on how doctors rank the various outcomes with which they are confronted by the incidental test results. The ranks of different outcomes are listed in a decision matrix that is converted into a two-by-two, non-zero, ordinal game. All scenarios of incidental test results emerge as a similar type of game that is best played by both parties adhering to the same set of strategies: 'Don't do the test' and 'don't respond to whatever test result it yields'. These two strategies lead to a Nash equilibrium for a non-zero game, where neither party can improve its payoff any further by choosing a different strategy. Although the equilibrium does not provide the individual players with their best possible payoff, it yields the best overall outcome available to both parties given the economic and medical constraints of the situation.