Psychometrics properties of self-reported pain sensitivity measures in individuals with shoulder pain

BackgroundCentral sensitization (CS) is increasingly recognized as a key contributor to persistent shoulder pain. While self-report tools such as the Central Sensitization Inventory (CSI) and the Pain Sensitivity Questionnaire (PSQ) are commonly used to assess CS, the psychometric properties of these tools have not been established in individuals with shoulder pain.ObjectiveThis study aimed to examine the convergent validity and test-retest reliability of the CSI and PSQ by comparing them with objective pain sensitivity measures.MethodsFifty-three adults with chronic shoulder pain completed the CSI and PSQ and underwent quantitative sensory testing including pressure pain threshold (PPT) and mechanical temporal summation (TS), while sensitivity to movement-evoked pain (SMEP) was assessed using a repetitive lifting task. Convergent validity was assessed using correlations analysis. Test-retest reliability was evaluated using intraclass correlation coefficients (ICC 3,1) and standard error of measurement (SEM).ResultsThe PSQ-Total (r = 0.30) and PSQ-Minor (r = 0.34) scores were significantly associated with SMEP at the symptomatic shoulder. No statistically significant associations were found between the CSI and QST or SMEP measures. Both the CSI and PSQ demonstrated moderate to excellent test-retest reliability (ICC range: 0.75-0.94).ConclusionThe PSQ demonstrated good reliability with modest convergent validity in assessing pain sensitivity during movement in individuals with shoulder pain. In contrast, the CSI did not correlate with objective measures, suggesting the CSI may assesses related but distinct constructs rather than direct measures of CS.