Table 3.

Univariate predictors of receiving adjuvant combined chemoradiation therapy among the 1,023 subjects who underwent gastrectomy.

Covariate		Chemoradiation therapy (%)	Odds Ratio (95% CI)	p-value
Age at diagnosis (per year increase)		30.2	0.88 (0.85, 0.90)	<0.0001
65 to 75		45.7	1.0	---
75 to 85		22.1	0.34 (0.25, 0.45)	<0.0001
85 and older		3.3	0.04 (0.02, 0.11)	<0.0001
Gender
Male		33.3	1.39 (1.06, 1.83)	0.0165
Female		26.4	1.0	---
Race
White		30.1	1.0	---
Asian		36.4	1.33 (0.94, 1.88)	0.1089
Other (including black)		21.2	0.63 (0.39, 1.01)	0.0542
SES Quintile (per quintile increase)		30.2	1.13 (1.03. 1.24)	0.0097
Six month diagnosis block (per 6 month increase)			1.10 (1.02, 1.19)	0.0161
Early 2000		20.6	1.0	---
Late 2000		33.8	1.96 (1.21, 3.17)	0.0061
Early 2001		29.6	1.62 (1.01, 2.61)	0.0478
Late 2001		29.7	1.63 (0.99, 2.68)	0.0555
Early 2002		36.4	2.20 (1.38, 3.51)	0.0010
Late 2002		32.2	1.82 (1.13, 2.94)	0.0135
T category
T1		38.0	1.0	---
T2		27.0	0.60 (0.33, 1.10)	0.0977
T3/T4		35.4	0.89 (0.48, 1.66)	0.7209
N category
N0		13.3	1.0	---
N1		35.8	3.64 (2.47, 5.36)	<0.0001
N2		41.8	4.69 (2.96, 7.45)	<0.0001
N3		56.8	8.60 (4.34, 17.07)	<0.0001
Grade
1		25.0	1.0	---
2		26.3	1.07 (0.44, 2.61)	0.8860
3/4		32.2	1.43 (0.60, 3.40)	0.4254
Charlson comorbidity score (per score increase)		30.2	0.81 (0.71, 0.93)	0.0019
0		32.0	1.0	---
1		35.2	1.15 ( 0.85, 1.56)	0.3600
2+		16.6	0.42 ( 0.27, 0.65)	0.0001
Gastrectomy at teaching hospital
Yes		30.8	1.06 (0.81, 1.39)	0.6554
No		29.5	1.0	---
Distance to RT facility (per additional mile)			1.00 (1.00, 1.00)	0.1032
Less than 45		29.6	1.34 (0.85, 2.11)	0.2118
45 or more		36.0	1.0	---
SEER Region
Northeast		29.6	0.85 (0.62, 1.17)	0.3287
South		25.4	0.69 (0.45, 1.06)	0.0918
Midwest		24.5	0.66 (0.41, 1.07)	0.0893
West		33.0	1.0	---

Abbreviations: SES=socioeconomic status, T=tumor, N=lymph node, RT=radiation therapy.