Vol. 9, Issue 3, Part A (2025)

Vitamin D is recognised not only for its role in calcium and phosphate homeostasis and skeletal health but also for its influence on muscle strength, neuromuscular function and pain modulation. Despite abundant sunlight in many regions, vitamin D deficiency remains a global public‑health concern, with estimates of up to one billion individuals affected worldwide. Adults presenting with diffuse musculoskeletal pain described as generalized aching in muscles, bones or joints without defined local pathology may harbour underlying vitamin D insufficiency or deficiency, yet routine screening remains inconsistent. Observational data indicate that lower serum 25‑hydroxyvitamin D [25(OH)D] levels are common among adults with non‑specific musculoskeletal pain, and interventional studies suggest that supplementation may reduce pain severity, though findings are heterogeneou. The present research aims to evaluate whether a simple symptom‑based screening tool (consisting of diffuse muscle aches, bone pain, proximal muscle weakness, fatigue, reduced sun exposure) can help identify adults at risk of vitamin D deficiency, and to investigate the association between vitamin D status and the prevalence and severity of generalized musculoskeletal pain. Secondary objectives include determining the prevalence of laboratory‑confirmed vitamin D deficiency (serum 25(OH)D < 20 ng/mL) in the target population and exploring the correlation between 25(OH)D concentration and pain burden (number of pain sites, duration, intensity). We hypothesise that participants who screen positive on the brief symptom checklist will have a significantly higher prevalence of vitamin D deficiency compared with those who do not, and that lower serum 25(OH)D concentrations will correlate with higher pain severity and greater number of pain sites. If validated, this simple screening approach may facilitate early identification of a modifiable risk factor for generalized musculoskeletal pain in adult outpatients, thereby supporting timely laboratory testing, supplementation, and lifestyle advice.