Contemporary studies of blunt head trauma and its determinants are important for prevention. It is also important to understand the strengths and limitations of the common sources of data used for the ongoing study of these injuries. Using the Ontario Trauma Registry, we described frequent patterns of blunt head trauma and identified priorities for prevention and research. A review of methodological issues that arose during the analysis of these trauma registry data is also provided. Blunt head trauma cases were identified within two data sets of the Ontario Trauma Registry. The Minimal Data Set is population-based and contains acute care injury hospitalizations, and the Comprehensive Data Set contains "major injuries" treated at a lead trauma hospital. Injury control priorities varied by age group, sex and data set and these are profiled in the manuscript. The results indicate the importance of examining multiple sources of surveillance data in establishing injury control priorities. The methodological review demonstrated the need to critically examine the completeness and accuracy of trauma registry data in arriving at decisions about priorities.