Table 6 Summary of study results.
| First author | Sample size | Outcome measured | Injuries in intervention group (A) | Injuries in control group (B) | Injury reduction (RR (95% CI)) | Absolute risk reduction | NNT |
|---|---|---|---|---|---|---|---|
| Emery | 114 | Self‐reported injury | 2 | 10 | 0.2 (0.03 to 0.72) | −0.19 (19%) | 5 |
| Jung | 194 | Injury per player per year | 0.76 | 1.18 | 0.73 | −0.195 (19%) | 6 |
| Injury per 1000 h exposure | 6.71 | 8.48 | |||||
| Mandlebaum | 2943 | ACL injury rate per athlete/1000 exposures/year | 0.05 | 0.47 | 0.255 | −0.18 (18%) | 6 |
| 2757 | 0.13 | 0.51 | |||||
| Olsen | 1837 | Number (%) of injured players (all injuries) | 95 (9.9%) | 167 (19%) | 0.49 (0.36 to 0.68) | −0.1 (10%) | 10 |
| Number of acute knee/ankle injuries | 85 | 156 | 0.51 (0.39 to 0.66) | ||||
| Number of overuse injuries | 18 | 39 | 0.43 (0.25 to 0.75) | ||||
| Knee and ankle injuries per 1000 player hours | 0.9 | 1.8 | 0.53 (0.35 to 0.81) | ||||
| Wedderkopp (1999) | 137 | Number of injuries | 14 | 66 | 0.198 | −0.26 (26%) | 4 |
| Injuries per 1000 h practice | 0.34 | 1.17 | |||||
| Injuries per 1000 h game | 4.68 | 23.38 | |||||
| Wedderkopp (2003) | 163 | Incidence of traumatic injury/1000 h practice | 0.2 | 0.6 | 0.42 when using ankle disc compared with no ankle disc training | −0.11 (11%) | 9 |
| Incidence of traumatic injury/1000 h match | 2.4 | 6.9 | |||||
| Hewett | 1263 | Number of serious knee injuries | 2/366 | 10/463 | 0.25 (0.06 to 1.15) | −0.015 (1.5%) | 66 (note these data reflect serious injuries; most were season ending) |
| Knee injury per 1000 exposures | 0.12 | 0.43 | |||||
| Non‐contact injuries per 1000 exposures | 0 | 0.35 | |||||
| Heidt | 300 | Total number of injured subjects | 6/42 | 87/258 | 0.42 (0.2 to 0.9) | −0.20 (20%) | 5 |
| Total number of injuries | 7/42 (16%) | 91/258 (35%) | −0.19 (19%) | ||||
| Grace | 580 | Number of knee injuries (diagnosed by doctor) | 42/330 | 11/250 | 2.88 | + 0.083 (+8.3%) * | Higher injury rate in intervention group |
| MacIntosh | 294 | Number of concussions (diagnosed by doctor) | 7/1179 | 2/357 | 1.05 | + 0.0003 (+0.03%)* | Higher injury rate in intervention group |
| Webster | 700 | Number of injuries per 1000 game exposures | 1.25 | 2.4 | 0.52 | Insufficient data | Insufficient data |
| Yang | 1 104 354 athlete exposures (19,728 athletes) | Lower extremity injury | Unable to calculate | Unable to calculate | 0.91 (0.72 to 1.15) when use of all protective equipment compared with control | 9% | Insufficient data |
ACL, anterior cruciate ligament; NNT, number needed to treat; RR, relative risk.
*+ indicates increased risk in intervention group.