Table 2

Intrinsic factors associated with injury incidence: univariate results

FactorN*IRIRR95%CIp Value
Demographic factors
 Age group<0.01
  13–1523116.31.00
  16–17111011.01.78(1.30 to 2.37)
  18–206958.51.34(0.92 to 1.96)
  21–2461815.52.44(1.77 to 3.36)
  25–34100013.82.22(1.67 to 2.97)
  35+45411.51.83(1.23 to 2.73)
 Ethnicity0.02
  Maori14359.51.00
  Pacific Island39615.41.63(1.11 to 2.40)
  Other44219.30.99(0.77 to 1.27)
Rugby experience
 Participation (years)<0.01
  0–37397.21.00
  4–56759.31.34(0.85 to 2.11)
  6–79288.21.12(0.72 to 1.74)
  85036.00.85(0.48 to 1.48)
  >8327011.71.62(1.13 to 2.33)
Anthropometric and physical performance factors
 Height (cm)<0.01
  <17419737.11.00
  174–17811449.61.39(1.01 to 1.91)
  179–18189511.51.67(1.20 to 2.31)
  182–185103012.21.77(1.30 to 2.40)
  >18592512.11.76(1.27 to 2.42)
 Weight (kg)<0.01
  <7423397.21.00
  74–8011009.41.29(0.95 to 1.76)
  81–8784711.71.66(1.21 to 2.26)
  88–9470011.31.55(1.11 to 2.18)
  >94119313.41.85(1.41 to 2.43)
 BMI (kg/m2)<0.01
  0–195685.80.66(0.42 to 1.04)
  20–2425298.91.00
  25–29206110.71.19(0.94 to 1.50)
  30+80114.41.59(1.20 to 2.11)
 Strenuous physical activity (hours per week)<0.01
  0–3958799.41.00
  40+37116.21.83(1.31 to 2.56)
Lifestyle factors
 Cigarette smoking0.29
  Non-smoker53869.61.00
  Ex-smoker17613.11.47(0.87 to 2.51)
  Current smoker64711.01.13(0.82 to 1.56)
Injury history
 Previous injury0.02
  None19118.51.00
  One24669.31.12(0.86 to 1.44)
  Two or more161812.21.45(1.11 to 1.89)
 Playing while injured<0.01
  No32347.51.00
  Yes295812.41.63(1.32 to 2.00)
  • * Number of player games.

  • p Value for the overall significance of the factor.

  • IR, incidence rate; IRR, injury rate ratio.