Objectives
Musculoskeletal pain is the single greatest cause of years lived with disability. This can include osteoarthritis, inflammatory disorders and musculoskeletal disorders such as back, neck, shoulder, hip, and knee pain. The Arthritis UK Musculoskeletal Health Questionnaire (MSK-HQ) was developed as a generic, single measure musculoskeletal outcome measure that can be used throughout the healthcare pathway and with patients with different musculoskeletal conditions.

Methods
The MSK-HQ was co-produced with patients and clinicians to identify aspects of MSK health that are important to both. A consensus workshop provided initial domains, and individual items were formulated. Stakeholder acceptability was measured using a second workshop and a candidate MSK-HQ was then taken forward to quantitative testing in physiotherapy and orthopaedic cohorts (n=570).

Results
The MSK-HQ was found to have face and content validity through the workshops, and was psychometrically robust, showing good completion rates, excellent test-retest reliability, and strong convergent validity with reference standards. Key outcome domains prioritised by patients with MSK conditions and seen as important across the clinical pathway were included within the MSK-HQ. These are captured using 14 items to measure pain severity (during the day and night), physical function (walking and dressing), work interference, social interference, sleep, fatigue, emotional health, physical activity, independence, understanding, confidence to self-manage, and overall-impact.

Conclusions
The MSK-HQ has been shown to be an excellent single, generic measure of musculoskeletal conditions, and has good psychometric properties of validity and reliability. It is acceptable to patients as relevant and easy to understand and has low levels of responder burden. Further work will encompass more validation studies, including factor structure and responsiveness, as well as cohort studies with rheumatoid/inflammatory arthritis.