Impact on respiratory tract infections of heptavalent pneumococcal conjugate vaccine administered at 3, 5 and 11 months of age

Table 5 Antibiotic courses prescribed during follow-up.

Episodes	PCV-7 group (n = 811)	Control group (n = 744)	RR	95% CI	P
Total number of antibiotic courses during follow-up	2,020	2,076
Courses/100 child-years	124	139	0.89	0.83–0.94	0.0001
Antibiotic courses in children aged 6–12 months	504	454
Courses/100 child-years	122	120	1.01	0.89–1.14	0.87
Antibiotic courses in children aged 13–18 months	620	658
Courses/100 child-years	153	177	0.86	0.76–0.95	0.004
Antibiotic courses in children aged 19–24 months	549	562
Courses/100 child-years	135	151	0.89	0.79–1.01	0.06
Antibiotic courses in children aged 25–30 months	347	402
Courses/100 child-years	85	108	0.78	0.67–0.90	0.0008