Table 2.

Univariate analysis of relative risk (RR) and 95% confidence interval (CI, Wald) for overuse injury (OI) in comparison to low-normal BMI for each training group

	Underweight	Low-normal	High-normal	Overweight	Obese
Infantry (n = 41,942)
Injured	2,284	9,495	5,784	3,319	1,014
	50.51%	50.91%	52.86%	54.71%	57.55%
Total	4,522	18,649	10,943	6,066	1,762
RR	0.9920	1.0	1.0381	1.0746	1.1303
95% CI	0.9607–1.0244	ref.	1.0149–1.0619	1.0461–1.1039	1.0833–1.1794
p	6.3×10−1 (ns)	ref.	1.3×10−3	2.6×10−7	1.1×10−7
Armor (n = 20,667)
Injured	1,128	4,417	2,591	1,805	719
	48.92%	49.81%	51.49%	55.57%	59.27%
Total	2,306	8,868	5,032	3,248	1,213
RR	0.9821	1.0	1.0338	1.1157	1.190124
95% CI	0.9373–1.0290	ref.	0.9992–1.0695	1.0750–1.1580	1.1308–1.2525
p	4.5×10−1 (ns)	ref.	5.7×10−2	1.9×10−8	5.8×10−10
Intelligence (n = 10,325)
Injured	292	1,210	731	413	146
	22.00%	25.48%	28.86%	31.97%	34.43%
Total	1,327	4,749	2,533	1,292	424
RR	0.8636	1.0	1.1327	1.2546	1.3515
95% CI	0.7718–0.9663	ref.	1.0475–1.2247	1.1429–1.3772	1.1748–1.5546
p	9.5×10−3	ref.	2.0×10−3	4.1×10−6	8.6×10−5
All (n = 72,934)
Injured	45.42%	46.87%	49.20%	52.21%	55.28%
RR	0.97	1.0	1.05	1.11	1.19
95% CI	0.94–0.99	ref.	1.03–1.06	1.09–1.14	1.14–1.23
p	0.02	ref.	4.2×10−7	1.5×10−21	1.0×10−20

p value for two-sided Fisher's exact test. Low-normal, BMI 18.50–21.99; high-normal, BMI 22.00–24.99.