Causes and length of hands-off time.

Note: Hands-off time was defined as the time that was longer than 1s between two consecutive compressions. Percentage of hands-off time = T2 (T2: hands-off time) / T1 (T1: total chest compression time). Percentage of hands-off time was presented as median (interquartile ranges) (non-parametric) and survival was presented as counts (percentage) (95% CI).Causes and length of hands-off time.