Fig. 3. Comparison of pain assessments with the Global Medication Performance Outcome Scale stratified by the baseline pain, measured at 30 min. Differences among the stratified lines are statistically significant (P < 0.001) for the raw pain intensity difference (PID) graph only (P < 0.0001). (A ) Raw change in pain intensity (raw PID; range 0–10). (B ) Percentage change in pain intensity (%PID; range 0–100%).