Trying to incorporate minor head injuries into studies is often more difficult than making a study of severe head injuries, doctors in many different areas note. Death and very severe injuries are noted by hospital records. When a minor head injury occurs with other more serious injuries, the head injury is often left out of reports. Concussions fall into this category.
The problem of insufficient documentation is worse in rural areas. Most minor head injuries go unreported there because people don’t bother to visit an Accident and Emergency department. When a hospital is involved, there are often a number of medical professionals that attend to the injury, including neurosurgeons, general or orthopedic surgeons, neurologists, geriatricians, and primary care physicians.
A Health Interview Survey study of USA households showed an annual estimated rate of head injury of 6 per 1000 of the population, but it also included facial injuries. Actual head injuries would probably be somewhat less than this, many studies on this subject note.