Are we ready to start? Introduction of community first responder system into Japan

high-incidence areas were defined as thosewith≥1 OHCAs every 2 years and low-incidence as thosewith <1OHCAs every 2 years. AED coverage of OHCAs was defined as the number of historical cardiac arrests occurring≤100mof anAED. Of 1864OHCAs, 18.0% (n=335) occurred in high-incidence areas, which accounted for 1.0% (1km2) of the city area. This proportion did not vary according to year. From 2007–2011, the number of registered AEDs increased 15-fold (from 36 to 552), and by 2011, there were 5.7 AEDs per km2, covering15.5% of the city area and nearly 1/3 of all of OHCAs (Table 1). Most AEDs were placed in areas with no previous OHCA (37.0%) or low-incidence areas (57.6%). Of all AEDs, 5.4% (n=30) were placed in high-incidenceOHCAareas and coverage ofOHCAs in these areas increased by 9-fold, from 5.7% to 51.3%. Conclusion: Increased AED dissemination resulted in coverage of nearly 1/3 of all historical OHCAs. The few AEDs placed in highincidence areas coveredmore thanhalf ofOHCAs in these areas, and nearly 1/10 of all OHCAs. A small number of AEDs, and thus, limited efforts by authorities would cover the remaining high-incidence areas.