%0 Journal Article %T Evaluating the psychometric properties of the Widespread Pain Index and the Symptom Severity Scale in youth with painful conditions %A Alagumeena Meyyappan %A Emily F. Law %A Jennifer A. Rabbitts %A Joanne Dudeney %A Tonya M. Palermo %J Canadian Journal of Pain %D 2019 %R https://doi.org/10.1080/24740527.2019.1620097 %X ABSTRACT Background: Assessing features of centralized pain may prove to be clinically meaningful in pediatric populations. However, we are currently limited by the lack of validated pediatric measures. Aim: We examined the psychometric properties of the Widespread Pain Index (WPI) and Symptom Severity (SS) scale to assess features of centralized pain in youth with painful conditions from three clinical samples: (1) musculoskeletal surgery, (2) headache, and (3) chronic pain. Methods: Participants were 240 youth aged 10 to 18 years (Mage = 14.8, SD = 1.9) who completed the WPI and SS scale. Subsets of participants also completed additional measures of pain region, pain intensity, quality of life, pain interference, and physical function. Results: Increased features of centralized pain by age were seen for the WPI (r = 0.27, P < 0.01) and SS scale (r = 0.29, P < 0.01). Expected differences in sex were seen for the WPI (sex: t132 = £¿3.62, P < 0.01) but not the SS scale (sex: t223 = £¿1.73, P = 0.09). Reliability for the SS scale was adequate (¦Á = 0.70). Construct validity was demonstrated through relationships between the WPI and pain regions (r = 0.57, P < 0.01) and between the SS scale and quality of life (r = £¿0.59, P < 0.01) and pain interference (r = 0.56, P < 0.01). Criterion validity was demonstrated by differences on the WPI between the surgery sample and the headache and chronic pain samples (F2,237 = 17.55, P < 0.001). Comprehension of the SS scale items was problematic for some youth. Conclusions: The WPI showed adequate psychometric properties in youth; however, the SS scale may need to be modified. Our findings support the need to develop psychometrically sound instruments for comprehensive assessment of pain in pediatric samples %U https://www.tandfonline.com/doi/full/10.1080/24740527.2019.1620097