system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 14-month-old Caucasian boy is admitted to the pediatric clinic with an 8-month history of diarrhea, abdominal tenderness and concomitant failure to thrive. One of the possibilities that may cause these symptoms is Crohn’s disease, and on the basis of the attending pediatrician’s experience, the pre-test probability of this diagnosis was estimated at 40%. According to Fagan’s diagram (picture), if the likelihood ratio of a negative test result (LR-) is 0.04, what is the chance that this is the right diagnosis?
assistant
2.5%