We would like to clarify some issues in Paul Carpenter's June 22 column about our motorcycle head injury study.
First, we reject his claim that we cannot draw conclusions about the 2003 helmet law change because motorcycle crashes result in more non-head than head-injury deaths. We found that over half the motorcycle deaths in Pennsylvania were from non-head injuries and the study included these data. But the purpose of the study was to assess changes in head injuries, given that a helmet law is meant to protect heads. We found that the rate of registration-adjusted head injury death and hospitalizations increased after the repeal; the most likely explanation, in agreement with most other studies was the significant decrease in helmet use post repeal.
Second, the column implies we incorrectly included some head-injury deaths. We followed federal guidelines for identifying traumatic brain injury deaths based on death certificates, which only list causes that directly lead to or contribute to death. Therefore, it is incorrect to assert that a motorcyclist who is cut in half and has a bump on his head would count as a head-injury death.
Helmets cannot prevent non-head injuries, nor can they prevent all head injuries. Thus, we support effective pre-crash safety measures. But, studies from around the world show that motorcycle helmets significantly reduce head injury risk and that mandatory helmet laws lead to increased helmet use and decreased head injuries.