Table 2.

Relative Incidence of Intussusception^a in the Risk Windows After the First and Second Doses of Monovalent Rotavirus Vaccine: Self-controlled Case-series Analysis

Dose of RV1	Risk Period	No. of Casesb	Relative Incidencec (95% CI)
1	Days 1–7	0	0
	Days 8–21	5	4.01 (.87–10.56)
	Days 1–21	5	3.14 (.66–8.49)
2	Days 1–7	15	1.71 (.83–3.01)
	Days 8–21	18	.96 (.52–1.60)
	Days 1–21	33	1.19 (.74–1.85)

Abbreviations: CI, confidence interval; RV1, Rotarix.

^aOnset of intussusception was considered to be the date of onset for the first reported symptom, including onset of refusal to feed, vomiting, or bloody stools.

^bEight to 21 days post–dose 1: human immunodeficiency virus (HIV) infected, n = 1; HIV-exposed but uninfected (HEU), n = 2; missing HIV status, n = 2. One to 7 days post–dose 2: HEU, n = 4; HIV unexposed, n = 4; missing HIV status, n = 7. Eight to 21 days post–dose 2: HIV unexposed, n = 5; missing HIV status, n = 13.

^cRelative incidence is a ratio of the incidence within the risk window vs the incidence in all other observation windows for each infant, calculated with the use of conditional Poisson regression.