Using Colors to Assess Pain in Toddlers: Validation of "The Rainbow Pain Scale"-AProof-of-Principle Study

Self-report, when available, is considered the ideal way to assess the intensity and other aspects of pain in children. However, self-report scales are often too complex cognitively for preschool-aged children (2-4 years). The Rainbow Pain Scale (RPS) was developed to provide individualized self-reported pain ratings for preschool-aged children. The psychometric properties of this scale have yet to be evaluated. To ensure validity, our first step was to compare RPS scores to a well-validated scale in older children who were able to self-report their pain. The purpose of this study was to assess the concurrent validity of the RPS in children aged 5 to 10 years as proof of principle. We compared ratings of 49 children's pain using the RPS with those on the Faces Pain Scale-Revised (FPS-R). Participants suffering from pain related to cancer and cancer treatment were recruited to complete both scales at 3 time points, during both inpatient and outpatient clinic visits. Pearson's r and Cohen's were used to evaluate the level of association between the scales. The association between RPS and the FPS-R was greater than .7 at all 3 visits; r = .96 between the scales at the first clinic visit, .97 at the second visit, and .93 at the third visit. Cohen's between scales was 1.0 at the first clinic visit, .95 at the second visit, and .87 at the third visit. The RPS shows excellent concurrent validity with the FPS-R in school-aged children. The next step will be to examine the psychometric properties of the RPS in preschool-aged children.