Altogether 553 children (195 first graders, mean age 6.8 years, and 358 third graders, mean age 8.7 years) participated in the development of a self-report measure to assess the intensity of children's pain. The first step was the derivation, from children's drawings of facial expressions of pain, of 5 sets of 7 schematic faces depicting changes in severity of expressed pain from no pain to the most pain possible. With the set of faces that achieved the highest agreement in pain ordering, additional studies were conducted to determine whether the set had the properties of a scale. In one study, children rank-ordered the faces on 2 occasions, separated by 1 week. All 7 faces were correctly ranked by 64% (retest 1 week later, 61%) of grade 1 children and by 86% (retest 89%) of grade 3 children. In a second study, the faces were presented in all possible paired combinations. All 7 faces were correctly placed by 62% (retest 86%) of the younger and by 75% (retest 71%) of the older subjects. A third study asked children to place faces along a scale: a procedure allowing a check on the equality of intervals. The fourth study checked on whether pain was acting as an underlying construct for ordering the faces in memory. We asked whether children perceived the set as a scale by asking if memory for an ordered set of faces was more accurate than for a random set. The final study checked, with 6-year-old children, the test-retest reliability of ratings for recalled experiences of pain. Overall, the faces pain scale incorporates conventions used by children, has achieved strong agreement in the rank ordering of pain, has indications that the intervals are close to equal, and is treated by children as a scale. The test-retest data suggest that it may prove to be a reliable index over time of self-reported pain.

A prospective observational study of cohorts of patients undergoing hip replacement (30), knee replacement (31), and spinal nerve root decompressive surgery (30) were interviewed pre-operatively to identify factors which might correlate with and potentially predict severe post-operative pain and dissatisfaction with analgesic management. The hip patients comprised 33% females and averaged 64 years, while the knee patients were 45% female and older (mean 71 years) and the spinal patients were 43% female and averaged 50 years. The three groups were similar with respect to all other pre-operative variables. Pain intensity was assessed mainly by self-report using the Present Pain Intensity (PPI) and Visual Analogue Scales (VAS) of the McGill Pain Questionnaire. The PPI was preferred by patients and nurses and, as there were no analytical advantages for the VAS, the PPI data are presented. The average post-operative pain during routine management mainly with patient controlled intravenous opiate, was mild to moderate and declined over days 1-5, declined further at discharge but rose slightly 1 month after discharge. The hip replacement patients experienced significantly (P < 0.01) less pain overall than the patients in the other two groups. Nurses' assessments of pain severity from observed behaviour were low and agreed poorly with the patients' self reports. Assessed on Likert Scales (0-6), the patients generally indicated good or excellent pain control, better than expected pain experience, and high levels of satisfaction with analgesic management. Significant (P < or = 0.01) multivariate correlates of severe post-operative pain assessed by logistic regression analysis of 11 variables were female gender, high pre-operative pain severity, and younger age. Significant (P < or = 0.01) multivariate correlates of both worse than expected pain experience and low satisfaction were female gender, high pre-operative pain severity, high anxiety about risks and problems, low expected pain severity, age (younger) and high willingness to report pain. These variables may reasonably be tested in further studies as potential predictors of adverse post-operative pain experience.

In children, single doses of ibuprofen (4-10 mg/kg) and acetaminophen (7-15 mg/kg) have similar efficacy for relieving moderate to severe pain, and similar safety as analgesics or antipyretics. Ibuprofen (5-10 mg/kg) was a more effective antipyretic than acetaminophen (10-15 mg/kg) at 2, 4, and 6 hours posttreatment.