Table 3

Subgroup analyses of injury proportions for the intervention and control group

Intervention group
n (%)
Control group
n (%)
Crude difference
% (95% CI)
Adjusted OR*
(95% CI)
Adjusted risk ratio
(95% CI)
Distance running event
 10/10.55 km137 (30.1)130 (29.6)0.5 (−5.7 to 6.6)1.08 (0.80 to 1.45)†1.06 (0.87 to 1.29)†
 15/16.1 km88 (32.8)87 (32.7)0.1 (−8.1 to 8.3)1.08 (0.75 to 1.58)†1.06 (0.83 to 1.34)†
 Half marathon102 (35.1)107 (37.2)−2.1 (−5.9 to 10.1)0.94 (0.66 to 1.33)†0.98 (0.79 to 1.20)†
 Marathon392 (38.9)393 (38.0)0.8 (−3.4 to 5.1)1.03 (0.86 to 1.24)†1.03 (0.92 to 1.14)†
Sex
 Male477 (36.7)466 (36.7)0.1 (−3.7 to 3.8)1.03 (0.87 to 1.21)‡1.02 (0.92 to 1.26)‡
 Female242 (33.4)251 (33.2)0.2 (−4.6 to 5.1)1.03 (0.83 to 1.28)‡1.02 (0.89 to 1.18)‡
Running experience§
 ≤1 year82 (39.0)90 (36.1)2.9 (−6.2 to 12.1)1.15 (0.78 to 1.69)‡1.10 (0.87 to 1.39)‡
 >1 year637 (35.2)627 (35.3)−0.1 (−3.1 to 3.3)1.02 (0.89 to 1.17)‡1.02 (0.93 to 1.11)‡
Previous RRI
 Yes439 (44.8)438 (42.9)1.9 (−2.5 to 6.4)1.09 (0.91 to 1.30)¶1.05 (0.95 to 1.16)¶
 No280 (26.8)279 (27.7)−0.9 (−3.0 to 4.8)0.96 (0.79 to 1.17)¶0.97 (0.84 to 1.12)¶
Reported RRI at baseline
 Yes166 (47.3)191 (46.4)0.9 (−6.3 to 8.2)1.05 (0.79 to 1.39)**1.02 (0.88 to 1.18)**
 No553 (33.1)526 (32.6)0.5 (−2.8 to 3.8)1.03 (0.89 to 1.19)**1.02 (0.92 to 1.13)**
  • *Control group is reference.

  • †Adjusted for the variables age, BMI, RRI 12 months before baseline, weekly training frequency and weekly training distance.

  • ‡Adjusted for the variables age, BMI, RRI 12 months before baseline and reported RRI at baseline.

  • §Running experience is missing for three participants.

  • ¶Adjusted for the variables age and reported RRI at baseline.

  • **Adjusted for the variables age and BMI.

  • BMI, body mass index; km, kilometre; RRI, running-related injury.