A comparison of four self-report scales of pain intensity in 6- to 8-year-old children

The study data show that the 4 pain intensity assessment instruments studied measure 1 common factor but that they are not concordant. There are many different instruments for assessing pain intensity in children, but the agreement between them is unclear. The aims of this study were to determine the 1-dimensionality of 4 widely used self-report scales for measuring the intensity of pediatric pain, and the agreement between them. A sample of 126 school children between 6 and 8 years of age (mean=6.87years; SD=0.68year) were interviewed individually and asked to identify the most frequent pain that they had experienced in the 3months before the interview, and to report their maximum pain intensity using all 4 scales (Visual Analogue Scale, Coloured Analogue Scale, Faces Pain Scale—Revised and Numerical Rating Scale—11). A factor analysis was conducted to determine the 1-dimensionality of these 4 scales. Agreement was calculated with the Bland–Altman method with a maximum limit of agreement set at ±20mm. Our data show the 1-dimensionality of the scales. The 95% limits of agreement between each pair of measures were as follows: VAS/CAS (−23.8, 23.4); VAS/NRS-11 (−41, 31.1); VAS/FPS-R (−38.3, 33.6); CAS/NRS-11 (−35.6, 26.2); CAS/FPS-R (−36.4, 32.1), and FPS-R/NRS-11 (−36.3, 31). Our data suggest that these 4 instruments measure 1 common factor but that they are not concordant.