Clinically significant changes in acute pain in a pediatric ED using the Color Analog Scale

Abstract

Objective The purpose of this study is to quantify, using the Color Analog Scale (CAS), the degree of change in pain severity required to achieve a clinically significant improvement in pain. Methods A prospective descriptive study, using convenience sampling of children aged 5 and 12 years presenting to a pediatric emergency department (ED) with acute pain, was done. Children were asked to mark their pain severity on a previously validated CAS. After a pain intervention, the child was again asked to mark their pain intensity on the CAS and asked to describe the relative change in their pain. The main outcome measure was to quantify the smallest change required for the child to state that their pain was improved. Results One hundred twenty-six children with a mean age of 8.6 years (SD, 2.8 years) were enrolled. Males accounted for 56%. Pain was traumatic in 47.6% and nontraumatic in 52.4%. Of the 126 pain comparisons made, 28 children described their pain as “the same” and had a mean change in score of −0.10 cm (95% confidence interval [CI], −2.27 to 2.07 cm). Pain was judged to be a “little less” in 58 children, and the CAS score changed by a mean of −2.4 cm (95% CI, −3.15 to −1.72 cm). In the 29 children who judged their pain to be “much less,” the CAS score decreased by a mean of −5.4 cm (95% CI, −6.50 to −4.40). Conclusion A decrease on the CAS pain scale of 2.4 cm (95% CI, 2.95–1.92) is a clinically significant change in pain for children aged 5 to 12 years with acute pain. The CAS is a valuable tool in assessing responses to pain interventions.