Essentially, 3 online databases (PubMed, Embase, and Cochrane Library) were searched for all studies of ACL injuries per athlete-exposure (AE) or hours of exposure in adolescent athletes. 
PubMed
Essentially, 3 online databases (PubMed, Embase, and Cochrane Library) were searched for all studies of ACL injuries per athlete-exposure (AE) or hours of exposure in adolescent athletes. 
Embase
Essentially, 3 online databases (PubMed, Embase, and Cochrane Library) were searched for all studies of ACL injuries per athlete-exposure (AE) or hours of exposure in adolescent athletes. 
Cochrane Library