Harcourt spoke to AFL.com.au following the presentation of findings on Tuesday that investigated the response when children were concussed playing sport.
The research by the Murdoch Children's Research Institute found that the "on-field management of sport-related head injuries in children did not follow international guidelines and that many children continued to play despite signs of concussion".
Harcourt said if children were not quite themselves after playing football, their parents needed to consider concussion as a possible explanation.
"Often they will get a knock to the head and not remember it and then the kid will be just a bit irritable after the game," Harcourt said.
If that happened, it was important the child and their parents received advice from doctors specialising in sports medicine.
Despite perceptions, Harcourt said there was no scientific evidence that helmets protected children from concussion, although wearing helmets while playing sport was not discouraged.
"The helmets provide good soft-tissue protection but [the answer to] whether or not they provide protection for concussion is uncertain," Harcourt said.
In fact, he said, some suggested wearing a helmet might make children more aggressive and, because of their size, more likely to experience contact to the head.
The AFL Medical Officers Association released community guidelines for the management of concussion in April after the Consensus Statement on Concussion was released.
The AFL also made position statements on the role of helmets and mouthguards in Australian football.
Harcourt said there was increased awareness of what needed to happen when parents suspected a child had been concussed, and information was available.
However, the research indicated putting the ideal processes into practice was still a work in progress.
Harcourt said parents should be aware that rest was needed after concussion and managing the child's recovery in the following days was important.
"For children, the most critical question during the recovery phase is their attendance at school. The issue for kids is not so much sport: it's more school because they need rest – and cognitive rest – to rest their brain. In schools kids tend to be pretty active and may expose themselves inadvertently [to knocks]," Harcourt said.