I have never heard of this method used for testing or evaluating someone with or suspected to have a concussion or mild traumatic head/brain injury. I could make an argument that this practice borders on incompetence.

Best to start with objective measures of balance. Look at vestibular system functionally, without touching his/her head (sit/stand, turn r/l, etc.). Look to visual system to establish that this system is working properly, and observe for nystagmus. Proceed gently into vestibular rehab with head turn while walking, VOR testing, etc.

Best not to scare the child/parent! Push for pre-concussion baseline testing in your area.

"Are mild TBI pediatric patients usually tested with head-shaking at 1-2 weeks". I should hope not. 1 to 2 weeks likely isn't enough for the CNS to fully recover for the initial injury, particularly if patient is still in rehab. I do not see patients, but study repeated mild trauma models in rodents. Very mild concussions (any one of which shows little effect) are indeed additive. Follow Kristen's more restrained advice above.

There is  a standard exam to evaluate positional stability in patients who have mTBI. I believe this evaluation would give you the inormation you are looking for in this head shaking maneuver. The exam is easy to do,reproducable and very helpful in evaluating patients with mTBI. If you are unfamiliar with it I would be happt to discuss it with you [email protected],856-392-9677

Studies have shown that the 1st 7-10 days is the period of greatest risk for incurring a second concussion.  In mild TBI there is cellular damage as well as micro-structural damage, and it is imperative that we keep external forces to the brain at a minimum to allow healing.  Studies are showing that the younger children require longer time to recover and we need to be conservative with our return to sports and recreational activity that has the potential to cause re-injury.  Best NOT TO SHAKE THE HEAD!!