TABLE 2.

Number of Intussusception Cases Occurring by Chance During the 3 Weeks After Vaccination in a Hypothetical Scenario in Which 1 Million Infants Are Vaccinated by Varying Weeks of Age (Based on All 39 Participating HCUP States During 1993–2004, Excluding 1999 When RotaShield Was in Use)

Age, wka	Predicted Rate (per 100 000 Infants)	Expected No. of Cases During a 3-wk Period in 1 Million Vaccinated Infants
6	4.9	3
9	9.2	5
12	18.6	11
15	30.6	18
18	42.5	25
21	53.1	31
24	60.2	35
27	61.6	36
30	59.9	35
33	57.7	33

^aDifferent scenarios under which all 1 million doses of vaccine are administered to children of a single age group.