Table 1. Age distribution of dogs presenting with HRI to veterinary practices participating in SAVSNET from 2013 to 2018, compared to the ages of dogs from the overall SAVSNET population demographic and dogs under primary-veterinary care in 2016 from the VetCompass programme.

Age	Number of HRI cases (n = 146)	Percentage of all HRI cases (%)	Percentage of SAVSNET demographic (%)	Percentage of VetCompass demographic (%)
<2 years	29	19.86	23.85	25.89
2–<4 years	28	19.18	14.33	19.68
4–<6 years	35	23.97	13.40*	15.46*
6–<8 years	19	13.01	13.19	12.52
8–<10 years	10	6.85	12.74*	10.05
10–<12 years	11	7.53	11.14	7.32
≥12 years	11	7.53	11.35	7.71
Unrecorded	3	2.05		1.37

Significant difference between HRI case population and SAVSNET or VetCompass demographic population indicated by * p < 0.05.