Health Belief Model Correlates of Behavioural Response to Diabetic Retinopathy Warning Signs Among Older Adults with Type 2 Diabetes: A Cross-Sectional Study in Rural Northeast Thailand - Weerasak Aneksak; Doonnaput Khowhit; Nakkharot Daengwongsa; Aranya Chaithawatwibun; Natthawut Suriya (National Journal of Community Medicine, 2026)