Unconditional logistic regression analyses of prehospital LR solution use and outcomes among patients with OHCA: 2005–2009 national data in Japan (n = 531,854).

aSelected variables included cases by year, age, sex, bystander eyewitness, relationship between bystander and patient, bystander chest compression, bystander rescue breathing, use of public-access AED by bystander, first documented rhythm, origin of OHCA, time from call to arrival at the scene, and time from call to arrival at hospital. These variables have been shown to be factors in resuscitation outcome.bAll covariates included all variables except for the endpoint variables in Table 1 and 46 dummy variables for the 47 prefectures in Japan.