Table 4.

Duration of interval between penicillin injections as risk factor for throat colonization with BHS

Interval between antibiotic prophylaxis	Culture positive	Culture negative	OR (95 % CI)	p-value
<16 days (n = 98)	15	83	1
17–21 days (n = 25)	5	20	1.4(0.5–4.3)	0.57
22–28 days (n = 50)	16	34	2.6(1.2–5.9)	0.02
≥29 days (n = 38)	15	23	3.6(1.5–8.5)	0.003

CI confidence interval, OR odds ratio