IntroductionPain is a subjective experience. In children with limited understanding and communication skills, reliable assessment of pain is challenging. Self-reporting of pain is the gold standard of pain measurement. For children who are unable to self-report their pain, assessments made by their parents are often used as a proxy measure. The validity of this approach has not been conclusively determined. AimTo investigate differences in the assessment of pediatric pain between children, parents, nurses, and independent observers in the acute postoperative setting. MethodThree hundred and seven children (207 verbal, 100 nonverbal) undergoing elective day-case surgery were asked to participate in this quality of care audit. Pain scores given by verbal children, their parents, nurses, and independent observers were collected. A numerical rating scale or the Wong-Baker Faces Pain Scale was used. All participants were blinded from other scorers. ResultsFor verbal children, scores reported by patients and their parents did not differ significantly. Median [inter-quartile range (IQR)] scores by children, parents, nurses, and independent observers were, respectively, 2.0 (0-4.0), 2.0 (1.0-4.0), 0.0 (0-2.0), and 1.0 (0-2.0). In nonverbal children, median (IQR) scores by parents, nurses, and independent observers were 1.0 (0-3.0), 0 (0-1.0), and 0 (0-2.0), respectively. The agreement between the different scorers was statistically significant. ConclusionChildren's pain self-reports should be used wherever possible to guide management, but in their absence, parental pain scores can be reliably used as a surrogate measure. Nurses and independent observers produce lower pain scores than parents or children, which may result in inadequate treatment of pain.