Post-concussion syndrome
Though no universally accepted definition of postconcussive syndrome exists, most of the literature defines the syndrome as the development of at least 3 of the following symptoms: headache, dizziness, fatigue, irritability, impaired memory and concentration, insomnia, and lowered tolerance for noise and light. One complication in diagnosis is that symptoms of PCS also occur in people who have no history of head injury, but who have other medical and psychological complaints. In one study 64% of people with TBI, 11% of those with brain injuries, and 7% of those with other injuries met the DSM-IV criteria for post-concussion syndrome. Many of these PCS sufferers were misdiagnosed as having other unrelated conditions due to commonality of symptoms. (see diagnosis, below).
Concussions in sport
Concussions are also a significant factor in rugby union, another full-contact sport. In 2011, the sport's world governing body, World Rugby (then known as the International Rugby Board, or IRB), issued a highly detailed policy for dealing with injured players with suspected concussions. Under the policy, a player suffering from a suspected concussion is not allowed to return to play in that game. Players are not cleared to play after the injury for a minimum of 21 days, unless they are being supervised in their recovery by a medical practitioner. Even when medical advice is present, players must complete a multi-step monitoring process before being cleared to play again; this process requires a minimum of six days. In 2012, the IRB modified the policy, instituting a Pitchside Suspected Concussion Assessment (PSCA), under which players suspected of having suffered concussions are to leave the field for 5 minutes while doctors assess their condition via a series of questions. Players who pass the PSCA are allowed to return to play.