Outcome data for concussion, head injury and injuries to other body regions stratified by HG versus no-HG
| Study | N | No-HG exposures | HG exposures | No-HG SRC | HG SRC | No-HG superficial head injury | HG superficial head injury | No-HG all body regions combined | HG all body regions combined |
| McIntosh and McCrory34 | 294 | 357 player game hours | 1179 player game hours | n=2 *Relative Risk=0.94 95% CI (0.19 to 4.52) | n=7 | n=7 *Relative risk= 1.54 90% CI (0.63 to 3.75) | n=15 | – | – |
| Marshall et al 200530 | 304 | 4656 player weeks | 752 player weeks | Not reported | Rate ratio=1.13 95% CI (0.40–3.16) | Not reported | Rate ratio=0.59, 95% CI (0.19 to 1.85) | Not reported | Rate ratio= 0.96, 95% CI (0.75 to 1.23) |
| Delaney et al 39 | 278 | n=216 players | n=52 players | n=114 relative risk=2.65, 95% CI (1.23 to 3.12) | n=14 | n=151 relative risk=1.86, 96% CI (1.49 to 3.45) | n=15 | – | – |
| Hollis et al 33 | 3207 | n=985 players | n=671 players | 7.48 per 1000 player hours. *Relative Risk=0.68 95% CI (0.24 to 1.93) | 7.39 per 1000 player hours. | – | – | – | – |
| McIntosh et al 32 | 3686 | 1493 player game hours | Standard HG 1,128 player game hours | n=90 | n=85 with standard HG. Incidence Rate ratio=1.13, 95% CI (0.86 to 1.49) | n=106 | n=100 with standard HG. Incidence Rate ratio=1.14, 95% CI (0.84 to 1.54) | n=799 | n=828 with standard HG. Incidence Rate ratio= 1.16, 95% CI (1.04 to 1.29) |
| Modified HG 1474 player game hours | See above row for control group | n=19 with Modified HG. Incidence Rate ratio=1.06, 95% CI (0.70 to 1.60) | See above row for control group | n=22 with modified HG. Incidence Rate ratio=1.03 95% CI (0.67 to 1.58) | See above row for control group | n=175 with modified HG. Incidence Rate ratio=1.05 95% CI (0.78 to 1.41) | |||
| Chalmers et al 29 | 704 | 4223 player game hours | 1807 player game hours | – | – | – | – | n=4419 injuries. Incidence rate ratio:1.00 | n=1844 injuries. incidence rate ratio: 1.26 95% CI (1.00 to 1.50) |
| Archbold et al 21 | 811 | n=553 players | n=258 players | n=42 *relative risk=0.63, 95% CI (0.41 to 0.98) | n=31 | log rank=0.327; df=1; p=0.567) | Not reported | n=549 *relative risk=0.99 95% CI (0.99 to 1.00) | n=258 |
| McGuine et al 31 | 3050 | n=1545 players | n=1505 players | n=68 | n=62 risk ratio=0.98, 95% CI (0.62 to 1.56) | – | – | Not reported | Risk ratio= 0.91, 95% CI (0.64 to 1.29) |
*Denotes crude relative risk as calculated by authorsof the review to facilitate consistency of interpretation. - Denotes missingdata as outcome not analysed in the study.
HG, headgear; SRC, sports related concussion.