Table 3.

Child sex-specific IRs of asthma with recurrent exacerbations (ARE) per 1000 person-years, stratified by child age during follow-up.

Child age	N	Person- years	Number of cases	IR (95% CI)
2–4 years	17246	73282	346	18.55 (16.59, 20.52)
Female	8129	34744	137	15.84 (13.18, 18.5)
Male	9117	38538	209	20.89 (18.04, 23.74)
5–9 years	11466	34891	277	4.90 (4.32, 5.47)
Female	5496	16788	112	4.09 (3.33, 4.85)
Male	5970	18103	165	5.66 (4.79, 6.52)
10–19 years	3369	13167	111	2.41 (1.96, 2.86)
Female	1593	6034	46	2.13 (1.52, 2.75)
Male	1776	7133	65	2.65 (2.00, 3.29)

Abbreviations: CI=confidence interval; IR=incidence rates