Table 4.

Stratified analysis based on variables in which the P‐value of the interaction with the serostatus was <0.15

Effect	Odds ratio	95% CI	P‐value
Race = White
HSV‐1: positive vs. negative	2.18	1.35–3.52	0.001
HSV‐2: positive vs. negative	2.30	1.32–3.99	0.003
VCA: positive vs. negative	10.64	5.77–19.62	<0.001
Race = Black
HSV‐1: positive vs. negative	1.43	0.63–3.26	0.395
HSV‐2: positive vs. negative	1.43	0.57–3.59	0.453
VCA: positive vs. negative	6.75	1.43–31.91	0.016
Race = Other
HSV‐1: positive vs. negative	0.36	0.11–1.20	0.096
HSV‐2: positive vs. negative	0.23	0.04–1.26	0.089
VCA: positive vs. negative	1.96	0.52–7.37	0.319
Stratified analysis based on age
Age < 15
VCA: positive vs. negative	3.29	1.86–5.84	<0.001
Age ≥ 15
VCA: positive vs. negative	a
Stratified analysis based on DRB1 status
DRB1*15:01 or 15:03 = positive
HSV‐1: positive vs. negative	0.93	0.47–1.84	0.828
DRB1*15:01 or 15:03 = negative
HSV‐1: positive vs. negative	1.89	1.17–3.03	0.009

^a173 of 174 cases in the older age group were positive for EBV‐VCA antibody, compared to 127 of 200 for controls. Since there was only one negative case, the model was not stable in this age group.