Assessing central nervous system contributions to accelerate musculoskeletal pain diagnosis and treatment (AsCent): protocol for a mixed-method, prospective observational study.

introductionChronic musculoskeletal pain often extends beyond pathology alone. Augmented central pain processing is linked to pain severity, persistence and treatment outcomes. A practical clinical tool is needed to identify individuals likely to have persistent or worsening pain, likely due to augmented central pain mechanisms. Quantitative Sensory Testing (QST) offers mechanistic insight, while the Central Aspects of Pain (CAP) Questionnaire captures symptom profiles that potentially reflect central mechanisms. Combining a brief clinical QST protocol with CAP may support early risk stratification and guide personalised pain management. METHODS AND ANALYSIS: This prospective observational study will recruit 250 individuals with inflammatory arthritis, osteoarthritis, chronic low back pain or fibromyalgia from existing cohorts, primary or secondary care. Participants will complete validated patient-reported outcomes at baseline, 6 and 12 weeks, with no additional intervention. The risk stratification tool completed at baseline will include clinical QST (Pressure Pain Threshold, Temporal Summation of Pain, Conditioned Pain Modulation), tender point count and the CAP questionnaire. Baseline laboratory versions of the clinical QST, plus Heat Pain Threshold, Offset Analgesia and the Central Sensitisation Inventory short form-9 questionnaire, will provide pain profiling to evaluate the predictive validity and psychometric properties of the tool. Data collection will include demographics, medical history, cognitive and neurological assessments and sleep quality via actigraphy (Actigraph wGT3X-BT). Interviews with patients and healthcare professionals will inform refinement, feasibility and acceptability of the tool. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Yorkshire & The Humber-South Yorkshire Research Ethics Committee (reference number: 24/YH/1062). Findings will be disseminated through peer-reviewed publications, conference presentations and patient-facing summaries and podcasts. The study aims to develop a clinically feasible tool to identify individuals at risk of persistent or worsening pain due to augmented central pain processing, enabling targeted treatment strategies. TRIAL REGISTRATION NUMBER: NCT06518278.