Fig. 3From: Using part of the initial analgesic dose as the epidural test dose did not delay the onset of labor analgesia: a randomized controlled clinical trialKaplan-Meier survival curve for the onset time of analgesia in RF and L groups. The results of the Cox model (concomitant variables: age, height, weight) indicated that no difference between group RF and group L (P = 0.47)Back to article page