Fig. 1
Model of a prophylactic treatment. The model is based on three time periods t = 0, 1, 2 with health states hh, hs and constant transition probabilities pA, pNA for adherence and non-adherence, respectively. Because the medical concept of adherence implies acceptance of the treatment contract [1], the consequences of rejection of the contract are not shown in detail. (Under the assumptions made, the path after rejection is identical to the path after acceptance followed by non-adherence)