• surveillance
• emergency departments

Although most routine health statistics provide information on injuries, the level of detail is often insufficient for injury prevention purposes. To fill this gap, many industrialised countries have introduced specially designed national and local injury surveillance systems based in emergency departments. Examples have been reported from Australia, Canada, Greece, New Zealand, the Netherlands, Norway, Sweden, the United States, and the UK.¹ The European Home and Leisure Accident Surveillance System (EHLASS) operates in the 15 current member states of the European Union. The EHLASS system collects data on all (or most) patients presenting with an injury or poisoning to a sample of hospitals. Because of the high costs of data collection, the usefulness and cost effectiveness of such systems is coming under increasing scrutiny.

Surveillance has been defined as the “continuous analysis, interpretation and feedback of systematically collected data”.² Injury surveillance systems have a number of important virtues. They monitor injury incidence, identify risk factors, and assist in the planning and evaluation of injury prevention programmes.³ Emergency department based systems have helped fill a major gap in our understanding of non-fatal injuries, which comprise a large (but usually unknown) proportion of medically treated injuries. In comparison with routine data sources, these systems provide greater detail and are timely. Moreover, their stability over time allows the analysis of secular trends and the identification of rare events, and new and emerging hazards such as a dangerous new toy.

Nevertheless, in spite of these advantages, several crucial questions regarding emergency department surveillance need to be addressed. The United States Centers for Disease Control have developed criteria for evaluating any surveillance system. …