TABLE 2.

Multivariable regression results—traumatic brain injury overall compared with orthopedic injury^a

	3 mo 95% CI				3-6 mo 95% CI				6-12 mo 95% CI
Outcome	Effect	LL	UL	P	Effect	LL	UL	P	Effect	LL	UL	P
Overall
Indirect costs (absolute difference)
Days of work missed	6.23	5.35	7.11	<.0001	13.22	9.22	17.22	<.0001	0.46	−0.54	1.45	.366
Miles traveled	6.26	−8.73	21.24	.413	3.09	2.17	4.01	<.0001	2.14	−2.23	6.52	.338
Travel expenses, $	0.07	−17.19	17.32	.994	10.39	−1.88	22.65	.097	−3.19	−16.90	10.51	.648
Time spent on healthcare encounters, h	−0.16	−1.84	1.51	.850	0.81	−0.15	1.77	.099	1.11	−0.18	2.39	.092
Direct costs (odds ratio)
ED visit	3.04	1.12	8.24	.029	5.00	1.08	23.24	.040	2.38	0.64	8.90	.198
Hospital admission	1.29	0.49	3.40	.608	0.28	0.01	10.63	.492	0.79	0.24	2.60	.697
OTC medications	1.17	0.79	1.73	.437	1.98	1.34	2.94	.001	1.43	0.98	2.09	.066
Prescription medications	0.81	0.51	1.27	.353	2.34	1.19	4.59	.013	1.74	0.84	3.58	.135
Site 1
Indirect costs (absolute difference)
Days of work missed	8.12	6.89	9.34	<.0001	3.75	2.44	5.06	<.0001	3.65	2.01	5.28	<.0001
Miles traveled	34.36	13.04	55.67	.002	28.65	21.70	35.60	<.0001	11.15	4.23	18.06	.002
Travel expenses, $	29.28	21.60	36.96	<.0001	39.94	−12.79	92.67	.138	3.54	−13.22	20.31	.679
Time spent on healthcare encounters, h	0.67	−0.47	1.80	.248	2.27	0.86	3.68	.002	1.78	−0.26	3.82	.087
Direct costs (odds ratio)
ED visit	2.39	0.57	9.99	.232	22.06	1.16	420.65	.040	…	…	…	…
Hospital admission	4.40	0.40	48.58	.226	…	…	…	…	2.14	0.32	14.33	.431
OTC medications	1.40	0.79	2.49	.254	2.30	1.33	3.98	.003	1.50	0.88	2.55	.132
Prescription medications	0.96	0.47	1.95	.913	6.53	1.78	23.91	.005	2.94	0.91	9.53	.072
Site 2
Indirect costs (absolute difference)
Days of work missed	5.21	3.91	6.52	<.0001	4.13	2.23	6.03	<.0001	1.12	−1.03	3.27	.307
Miles traveled	−28.64	−35.63	−21.65	<.0001	−3.17	−8.91	2.57	.280	−8.08	−13.10	−3.06	.002
Travel expenses, $	−46.02	−80.22	−11.82	.008	−9.59	−18.56	−0.63	.036	−9.77	−37.57	18.04	.491
Time spent on healthcare encounters, h	−3.12	−6.17	−0.06	.045	0.04	−1.45	1.54	.954	0.06	−0.76	0.88	.894
Direct costs (odds ratio)
ED visit	6.61	1.11	39.37	.038	2.25	0.13	39.92	.581	…	…	…	…
Hospital admission	0.72	0.17	3.04	.660	…	…	…	…	0.22	0.01	4.49	.325
OTC medications	1.04	0.56	1.93	.889	1.73	0.92	3.26	.092	1.48	0.81	2.71	.201
Prescription medications	0.69	0.34	1.39	.303	2.00	0.79	5.08	.145	1.22	0.40	3.72	.726

Abbreviations: CI, confidence interval; ED, emergency department; LL, lower limit; OTC, over-the-counter; UL, upper limit.

^aRegressions controlled for age, sex, race, admission type, insurance type, parental employment, parental education, marital status, rurality, poverty level, receipt of government financial assistance, indicator for problematic family functioning, and Social Capital Index. Site-specific estimates for hospital admission during months 3 to 6 and ED visits during months 6 to 12 could not be generated because of insufficient number of events.