Table 2.

Assessment of risk of bias.

Author	A	B	C	D	E	F	G	H	I	J	K	L	M	No	Score
Alentorn-Geli 201553	No	No	Yes	U	No	No	U	No	U	U	U	U	U	Yes	2
Beynnon 200660	No	No	Yes	No	No	No	Yes	U	U	U	No	U	NA	Yes	3
Beynnon 2014a35	No	U	U	No	U	U	Yes	Yes	U	U	No	U	U	Yes	3
Beynnon 2014b42	No	No	Yes	U	No	U	U	Yes	U	U	Yes	Yes	U	No	4
Beynnon 2014c24	No	No	U	No	No	No	U	Yes	No	U	No	U	NA	U	1
Bisson 201034	No	U	U	No	U	U	Yes	Yes	U	U	U	U	U	Yes	3
Chaudhari 200948	No	U	Yes	U	U	U	U	Yes	U	NA	No	NA	NA	Yes	3
Dare 201541	No	U	U	Yes	U	U	U	Yes	U	U	No	U	No	Yes	3
Everhart 201029	No	No	Yes	No	U	Yes	Yes	Yes	No	U	No	U	NA	U	4
Fernández-Jaén 201528	No	No	Yes	U	No	No	U	No	U	U	No	U	NA	Yes	2
Flynn 200571	No	No	U	U	No	No	No	No	No	U	No	U	NA	No	0
Hägglund 201659	Yes	U	U	U	U	U	No	Yes	No	U	No	U	NA	Yes	3
Hewett 200555	Yes	U	Yes	U	U	U	U	No	U	U	No	U	U	Yes	3
Khayambashi 201651	Yes	U	No	U	U	U	Yes	Yes	U	U	Yes	Yes	U	No	5
Khoschnau 200863	No	No	U	U	U	No	U	No	U	U	No	U	NA	Yes	1
Kramer 200745	Yes	No	Yes	No	Yes	Yes	No	No	No	NA	NA	Yes	NA	Yes	6
LaPrade 199426	Yes	U	U	No	U	U	U	No	U	U	No	U	U	Yes	2
Lefevre 201361	No	U	No	U	U	U	U	U	No	U	No	U	U	No	0
Lund-Hanssen 199431	No	U	U	U	U	U	U	No	U	U	No	U	NA	Yes	1
Mannion 201469	No	U	U	U	U	U	U	Yes	No	U	No	U	U	Yes	2
Myer 200952	Yes	U	Yes	No	U	U	U	Yes	U	U	No	U	NA	U	3
Myer 201557	Yes	U	No	U	U	U	U	No	U	U	No	U	NA	U	1
Nilstad 201469	Yes	No	No	U	U	U	No	Yes	No	U	No	U	NA	No	2
O'Connell 201567	No	U	U	U	U	U	U	No	U	U	No	U	U	Yes	1
Orchard 199919	U	No	U	U	U	U	U	No	No	U	No	U	NA	U	0
Orchard 200520	No	No	U	U	U	U	U	Yes	No	U	No	U	NA	U	1
Parkkari 200823	Yes	U	NA	NA	U	U	Yes	No	No	Yes	No	U	NA	U	3
Pope 200222	Yes	U	U	U	No	U	U	No	U	NA	No	U	U	Yes	2
Posthumus 2009a65	No	U	No	No	U	U	U	No	No	NA	No	NA	NA	Yes	1
Posthumus 201066	No	No	Yes	No	No	No	No	No	U	U	No	U	NA	Yes	2
Posthumus 2009b64	No	No	Yes	U	No	No	No	Yes	U	U	No	U	NA	U	2
Posthumus 201268	No	No	Yes	No	No	No	No	Yes	U	U	No	U	NA	Yes	3
Quatman 201156	Yes	U	U	U	No	No	U	No	U	NA	No	NA	NA	Yes	2
Raschner 201249	No	U	U	No	U	U	No	U	U	U	No	U	NA	U	0
Ruedl 200962	No	U	Yes	U	U	U	No	Yes	U	U	No	U	U	No	2
Ruedl 201121	No	No	No	U	U	U	U	No	No	U	No	U	U	Yes	1
Ruedl 201272	No	No	No	No	No	No	U	Yes	No	NA	NA	NA	NA	Yes	2
Saper 201644	No	U	U	No	U	U	U	Yes	No	U	No	NA	NA	Yes	2
Shaw 201533	No	U	U	U	U	U	U	Yes	U	U	No	U	NA	Yes	2
Simon 201032	No	U	U	U	U	U	U	Yes	U	NA	No	NA	NA	Yes	2
Souryal 199325	Yes	No	U	NA	U	Yes	Yes	Yes	No	U	No	Yes	Yes	No	6
Stijak 201446	No	No	U	U	U	U	U	Yes	U	U	No	U	NA	Yes	2
Sturnick 2014a36	U	U	U	U	U	U	Yes	Yes	U	NA	No	NA	NA	U	2
Sturnick 2014b37	Yes	U	U	U	U	U	U	Yes	U	U	No	U	NA	Yes	3
Sturnick 201530	No	U	U	U	No	No	U	No	U	U	No	U	U	Yes	1
Tainaka 201458	No	No	Yes	U	Yes	U	U	Yes	U	U	No	U	NA	U	3
Terauchi 201139	No	No	U	U	No	No	U	Yes	U	U	No	U	NA	Yes	2
Todd 201040	No	No	U	NA	U	No	Yes	Yes	No	U	NA	Yes	NA	U	3
Uhorchak 200312	Yes	No	U	No	Yes	Yes	Yes	Yes	No	U	Yes	Yes	Yes	No	8
Vyas 201143	No	No	No	U	U	U	U	No	U	U	No	U	NA	Yes	1
Whitney 201447	No	No	U	No	No	No	U	Yes	U	U	No	U	NA	U	1
Xiao 201627	No	U	Yes	U	U	U	Yes	No	No	U	No	U	NA	Yes	3
Zazulak 200750	Yes	No	Yes	U	Yes	Yes	Yes	No	No	U	No	U	Yes	U	6
Zebis 200954	Yes	No	U	No	U	U	Yes	No	U	U	No	U	No	Yes	3
Zeng 201438	No	U	Yes	U	Yes	Yes	Yes	Yes	U	U	No	U	NA	Yes	6

Column Abbreviations: A = Prospective study; B = Concealed/blind group assignment; C = Group similarities at baseline; D = participant blinding; E = data collector blinding; F = outcome assessor blinding; G = previous knee injuries excluded; H = results specified for non-contact; I = no influence of other risk factors; J = acceptable compliance; K = dropout reasons reported; L = acceptable dropout rate; M = duration of intervention comparable; N = intention to treat analysis. Yes = criteria was explained and acceptable (1 point); No = criteria missing or not acceptable (0 points); U = Unknown, criteria not explained or unclear; NA = not applicable (0 points).