Table 1.

Incidence and OD-OHCA case proportion by site.

Site	All OHCA, n	OD-OHCA, n	Proportion OD-OHCA	Catchment population (in person-years)	Average OD-OHCA incidence (per 100,000 person-years)
A	1555	37	2.4%	2,827,529	1.2
B	5459	147	2.7%	4,981,666	1.9
C	6674	189	2.8%	9,452,687	0.9
D	8553	142	1.7%	12,091,062	0.9
E	13,679	213	1.6%	18,376,190	1
F	4538	152	3.3%	6,418,841	2.1
G	3640	29	0.8%	4,289,383	0.5
H	3350	123	3.7%	1,592,427	1.6
I	2724	78	2.9%	2,961,489	2.1
J	6100	241	4.0%	6,852,373	2.7
ROC	56,272	1351	2.4%	69,843,645	1.3

Abbreviations: OD-OHCA – overdose out-of-hospital cardiac arrest; ROC – Resuscitation Outcomes Consortium.