Reporting the Location and Extent of Pain in Adolescents: A Test-Retest Reliability Study

Background: A pain drawing is a self-administered assessment that requires the patient to shade in on a body chart the areas in which he or she experiences pain, regardless of the intensity. Pain drawings have already been validated in several adult populations. Objectives: The aim of this study is to establish adolescents' test-retest reliability in reporting the extent and location of their pain using a paper-based pain drawing. Study Design: A one-day test-retest reliability study was set up. Setting: The study took place in 2 separate locations-a pediatric hospital and a private physiotherapy practice in Ticino, in the southern part of Switzerland. This reliability study was approved by the local ethics committee of Ticino (2021-00492 CE 3832). Methods: Adolescents with musculoskeletal pain (aged 11-16 years) were included. All participants were asked to shade the areas in which they experienced pain over the previous week. After the administration of a questionnaire and the acquisition of further personal data, the pain drawing was administered again. The pain drawings were then scanned and analyzed using a digital platform, which allowed the extraction of pain extent and location values. The test-retest reliability was evaluated on these data. The intraclass correlation coefficient and Bland-Altman analysis were used to assess the reliability of the reporting of the pain extent, whereas the Jaccard similarity coefficient was used to calculate the reliability of the reporting of the pain location. Results: The reporting of the pain extent was observed to have excellent test-retest reliability: ICC2,1: 0.959 (95% CI: 0.925-0.978). The Bland-Altman analysis showed a mean difference close to 0: -0.010% (limits of agreements -0.962 to 0.942). The reliability of the reporting of pain location was also supported by the Jaccard index mean score of 0.82 (+/- 0.19). Limitations: Reliability of reporting may vary depending on the nature of the pain, its duration, or the type of disorder and body areas involved. Conclusions: Adolescents complaining musculoskeletal pain showed reliability in reporting pain extent and location using pain drawings