When do people visit a doctor?

We examine the length of time between when an individual feels sick and when he/she visits a doctor using survival analysis to capture the dynamic aspects of this behavior. If the disease is light, actions such as over the counter medicine or sick leave are alternatives to visiting a clinic or a hospital immediately. The timing of the visit depends only the person's decision, not on a doctor's, so we can limit discussion to the effect of ex-post moral hazard excluding physician induced demand. Participants were asked to keep a log of illness-related behavior such as dates of episodes, subjective symptoms, sick leaves, and medical treatment at hospitals. Neither the copayment rate nor access cost had a significant effect on the behavior of visiting a doctor, whereas available alternatives delay the timing of a visiting. Severe symptoms and fever hastened the time. The results suggest that the traditional argument about ex-post moral hazard is somewhat misleading.