What is the Haddon Matrix and how is it used in injury prevention?

The Haddon Matrix is a tool for analyzing injury risk based on the epidemiological triangle, with rows for the pre-event, event, and post-event phases and columns for host, agent, and environment. It is used to identify contributing factors at each phase and to plan injury prevention and mitigation strategies, such as preventing the event, reducing impact during the event, and improving outcomes afterward.

The Haddon Matrix was developed by William Haddon, Jr., the first head of the National Highway Traffic Safety Administration, and is based on the epidemiological triangle of agent, host, and environment. The matrix contains at least twelve boxes arranged in rows and columns: the rows represent the timing around an injury event (pre-event, event, and post-event), and the columns represent the host, agent (vehicle or equipment), and environment (physical and social). Filling in the boxes helps identify factors that contributed to an injury event and assists in planning interventions at multiple points, such as primary prevention before the event, mitigation during the event, and secondary or tertiary prevention afterward. Although originally created for motor vehicle crash analysis, the matrix can be applied to any injury category, such as patient falls in acute care settings. It also helps set up data collection and can be made three-dimensional by adding decision criteria such as effectiveness, cost, and feasibility to compare possible interventions.