Full model email address details are available in Table S4 in the Supplementary Appendix. <65 years), race , and sex . Secondary Outcomes Rates of acute resuscitation survival improved substantially in the overall cohort also, with a risk-adjusted rate of 42.7 percent in 2000 and 54.1 percent in ’09 2009 . This development was also significant for both rhythm groups . Temporal improvement in postresuscitation survival was somewhat smaller . In sufferers with ventricular fibrillation or pulseless ventricular tachycardia, there is no significant change with time to defibrillation . Although prices of survival to discharge increased, prices of clinically significant neurologic disability among survivors decreased over time in the overall cohort and in patients with ventricular fibrillation or pulseless ventricular tachycardia .Our instructions of 2 ventilations alternating with 15 compressions were maintained through the entire study, because the new guidelines did not address dispatcher-assisted CPR. Data were collected from EMS information, and information about survival position was collected from national registers. No interrater dependability assessment was performed. Nevertheless, 50 percent of the data-collection forms were double-checked and no relevant deviations were observed.