Here are some other resources:
https://bjsm.bmj.com/content/bjsports/early/2017/04/26/bjsports-2017-097506SCAT5.full.pdf
https://bjsm.bmj.com/content/bjsports/early/2017/04/26/bjsports-2017-097492childscat5.full.pdf
https://bjsm.bmj.com/content/51/11/838
Matrix is great for clinical work. If they are playing sports or need to return to school there protocols. just because they are cleared in the clnic does not necessarily indicate they are ready to to return to sport. Be humble and know who to refer to -:).