Dr. A. McKinlay from the University of Canterbury, Christchurch, and colleagues collected data on 132 children, younger than 10 years of age, who sustained a mild head injury. These children were divided into two groups, those who required inpatient care and those who did not. The outcomes of these children were compared with a control group of 613 to 807 children without head injury.

The children were also classified by age at injury, according to the report in the September issue of the Journal of Neurology, Neurosurgery and Psychiatry.

Based upon reports of mothers and teachers, children in the inpatient group had an increase in hyperactivity/inattention and conduct disorders between 10 and 13 years of age. These psychosocial problems also occurred more frequently among those children who were injured before 5 years of age, Dr. McKinlay's team found. No increase in these problems was seen among children in the outpatient group, they add.

Severity of head injury did not appear to affect performance on various cognitive and academic tests, the researchers note.

"Our findings provide an answer to the conflicting views on the effects of mild head injury in early childhood by showing that in many respects both sides of the debate are correct," Dr. McKinlay's group writes. "That is, the effect of mild head injury depends on whether it is of the more frequent instance that requires no inpatient care as compared with the more severe instance for which some inpatient observation may be warranted."

J Neurol Neurosurg Psychiatry 2002;73:281-288.