Table 4.

Univariate and multivariate analyses of DNBI rates among surveyed personnel aboard USNS COMFORT during CP11

	Total DNBI rates
	Univariate		Multivariatea
	IRR	p-value	IRR	p-value
Age
≤ 25 (referent)	1.00		1.00
26–35	1.17	0.049	1.23	0.009
36+	0.87	0.133	0.90	0.316
Gender
Male (referent)	1.00
Female	1.00	0.977
Rank
Enlisted (referent)	1.00		1.00
Officers	1.07	0.440	1.23	0.025
Civilian	0.76	0.024	0.93	0.934
Branch of service
Army (referent)	1.00
Air Force	1.60	0.144
Navy	1.65	0.087
NGO	1.30	0.412
Other	1.74	0.089
Days off Ship (continuous)	1.10	<0.001	1.09	<0.001
Location
Jamaica	0.75	0.036	1.07	0.672
Peru	0.70	0.025	1.03	0.889
Ecuador	1.60	<0.001	1.81	<0.001
Colombia	1.39	0.001	1.39	0.002
Nicaragua	1.13	0.366	1.61	0.002
Guatemala	1.24	0.072	1.64	<0.001
El Salvador	1.60	<0.001	2.06	<0.001
Costa Rica	0.81	0.072	1.10	0.472
Haiti	0.52	<0.001	0.84	0.270
Unit department
Air detachment	1.29	0.127	1.45	0.062
Boat detachment	0.70	0.316	0.93	0.837
DAS	0.82	0.166	1.05	0.795
Destroyer Squadron	0.71	0.278	0.75	0.374
DFA	0.97	0.805	1.11	0.539
Medical services	1.00	0.996	1.17	0.268
Surgical services	0.74	0.003	0.96	0.790
Nursing services	1.29	0.004	1.48	0.007
Maritime Expeditionary Security Squadron	0.73	0.286	1.13	0.698
Naval Mobile Construction Battalion	2.25	<0.001	3.17	<0.001
Manpower/Personnel	0.83	0.453	1.20	0.521
Security	1.27	0.025	1.71	<0.001
Information operations	0.63	0.062	0.71	0.210
Communications	1.17	0.546	1.39	0.247
Public Affairs Office/Band	1.29	0.174	1.35	0.164
Translator	0.90	0.665	1.01	0.969
Operations	0.93	0.799	1.16	0.589
Other	0.74	0.016	0.80	0.061

^aMultivariate analyses adjusted for age, rank and days off ship