Table 1

Study population

 Control classesTotal controlsInterventionTotal
2007200820092012
Starting class size, n1940187732109
RA drop-outs
 Injury, n (%)1 (5.3)01 (5.6)2 (2.6)1 (3.1)3 (2.8)
 Other, n (%)8 (42.1)5 (12.5)1 (5.6)14 (18.2)4 (12.5)18 (16.5)
Prob. year drop-out, n (%)1 (5.3)1 (2.5)2 (11.1)4 (5.2)04 (3.7)
Successful completion, n (%)9 (47.4)34 (85.0)14 (77.8)57 (74.0)27 (84.4)84 (77.1)*
Age, mean (SD)†25.3 (3.4)28.2 (5.8)29.3 (6.1)28.0 (5.7)28.4 (5.1)27.5 (5.3)
Female, n (%)3 (15.8)02 (11.1)5 (6.5)1 (3.1)4 (3.7)‡
  • *Successful completion differed significantly by year, p=0.013.

  • †Age at time of pre-employment physical. These data are missing for many recruits who failed to complete the RA. 2007: n=10; 2008: n=36; 2009: n=16; 2012, n=28 (p=0.41).

  • ‡Total does not equal column totals: one female participated in the 2007 and 2009 RAs; another female participated in the 2009 and 2012 RAs. These are treated as independent observations for the statistical tests (p=0.025).

  • RA, recruit academy.