To prevent injuries and violence, it is important to first understand the problem. What is causing the problem? Who is affected? What are the circumstances in which it occurs? To answer these questions and others, it is critical that data be collected. The IPC collects data from the medical examiner’s office, local hospitals, fire departments, police departments, EMS, schools and others. The data is used to identify populations at risk, determine risk factors, detect emerging issues, and design and evaluate prevention programs.