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 OTC 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.