Figure 4.

Kaplan–Meier analysis and results of log rank significance test of latency to burrow. The curves indicate the probability that a mouse with a given treatment has not yet started to burrow. The probability of non-burrowing (y-axis) is traced against the time to event in hours (x-axis). (A) Significant difference between groups treated (or not) with an analgesic for surgery. (B) Significant difference between groups of mice that underwent anesthesia and surgery without pain relief and mice that were anesthetized only. (C) The difference between the surgery + anesthesia group and the anesthesia + analgesia group was not statistically significant. (D) No significant differences in latencies to burrow were found between surgery + anesthesia + analgesia, anesthesia and anesthesia + analgesia groups.