Table 3.

Incidence rate ratios for targeted injuries, stratified by region (head and neck, shoulder and lower limb) based on Poisson regression analysis adjusted for cluster and playing level

Target injury and arm	Clubs (n)	Player match-hours	Injuries/days lost count	IIR(90% CI)	RR (90% CI)	Magnitude-based inference (beneficial/trivial/harmful) (%)
Head and neck incidence
Control	19	9660	35	3.6 (2.7 to 4.8)	0.3 (0.2 to 0.7)	Very likely beneficial (99/1/0)
Intervention	22	9900	12	1.2 (0.8 to 1.9)
Concussion incidence
Control	19	9660	33	3.4 (2.6 to 4.5)	0.4 (0.2 to 0.7)	Very likely beneficial (99/1/0)
Intervention	22	9900	12	1.2 (0.8 to 1.9)
Shoulder Incidence
Control	19	9660	10	1.0 (0.6 to 1.7)	1.7 (0.7 to 3.8)	Likely harmful (11/10/79)
Intervention	22	9900	17	1.7 (1.2 to 2.6)
Lower-limb incidence
Control	19	9660	50	5.2 (4.1 to 6.5)	0.6 (0.4 to 1.0)	Likely beneficial (89/9/2)
Intervention	22	9900	33	3.3 (2.5 to 4.4)
Head and neck burden
Control	19	9660	1164	120 (92 to 159)	0.3 (0.2 to 0.7)	Very likely beneficial (99/1/0)
Intervention	22	9900	378	38 (24 to 61)
Concussion burden
Control	19	9660	983	102 (76 to 136)	0.4 (0.2 to 0.8)	Very likely beneficial (97/2/1)
Intervention	22	9900	378	38 (24 to 61)
Shoulder burden
Control	19	9660	436	45 (27 to 76)	1.5 (0.6 to 3.7)	Possibly harmful (17/11/71)
Intervention	22	9900	673	68 (46 to 101)
Lower-limb burden
Control	19	9660	3688	382 (303 to 482)	0.6 (0.3 to 1.5)	Unclear (75/11/14)
Intervention	22	9900	2421	245 (184 to 326)

IIR, injury incidence rate; RR, rate ratio.