Figure 2.

Estimated probability surface of survival among patients with VF/VT, according to time to first defibrillation (≤ 10 minutes), and BLS CPR quality. CPR quality scale: 0 – No CPR; 1 – Intermediate quality; 2 – Compression and ventilations of good quality. Logistic regression coefficients with 95% confidence intervals in parentheses: Model r-square = 0.22, Intercept = 0.96 (-0.32 to 2.57), CPR quality = -1.01(-2.09 to -0.10), Log time (min) = -1.87 (-3.37 to -0.72), Interaction term = 1.01 (0.24 to 1.91).