How many fruitless visits would it be worthwhile to you to make for that one visit where something bad is found?

The negative utility generated by going to a public health clinic and gaining absolutely no useful information is, for me, on the order of 50 USD, assuming an average copay of around $30, and that my time is worth around $20.

If I want to simply model the expected utility of going to a clinic by assuming that I either will or will not gain useful information from going to the doctor, I might subtract:

[$50 x p(fruitless visit)]

from

[(monetary value of information gained from a helpful visit-$20) x (1-p(fruitless visit))].

where the -$20 in the second equation is to account for the value of my time in the event of a fruitful visit.