Table 2. Number of dog samples by titer range and age at primary vaccination.

Age at Primary Vaccination	<0.50 IU/ml	0.5–2.62 IU/ml	>2.62 IU/ml	Total Dogs	CMH* p-value	GMT	Lower 95% CL	Upper 95% CL	ANOVA p-value	Draw Interval (days, 95% CI)
< 12 weeks	48 (16.6%)	120 (41.4%)	122 (42.1%)	290		1.22	0.97	1.54		92 days (83–100)
12–16 weeks	346 (15.5%)	959 (42.9%)	933 (41.7%)	2,238		1.21	1.12	1.32		79 days (76–82)
>16 weeks	570 (10.4%)	1,965 (35.8%)	2,948 (53.8%)	5,483		1.64	1.57	1.72		64 days (62–65)
Total	964	3,044	4,003	8,011	<0.01	1.50			<0.01

*Cochran-Mantel-Haenszel