A Web-Based Diabetes Oral Self-Care Intervention (DiaOral©): Methodology and Intervention Validity Assessment

Background/Objectives: The American Diabetes Association (ADA) 2026 Standards of Care emphasize digital health and web-based technologies in diabetes self-management. However, few interventions support people with diabetes (PWD) in improving oral self-care behaviors or preventing oral diseases, despite their significantly higher oral health disparities. This study describes the methodology used from early ideation through prototype development and content-validity expert rating in the design phase of DiaOral©, a web-based oral self-care intervention for PWD guided by the Health Belief Model (HBM) and design-thinking principles. Methods: DiaOral© was developed using a four-step process: (1) ideation to identify content areas aligned with HBM constructs; (2) expert panel recommendations using an iterative refinement process to achieve consensus and finalize DiaOral models and draft content; (3) prototyping to create website wireframes based on design-thinking principles and integrate content into structured blocks; and (4) content-validity expert evaluation of the prototype by a multidisciplinary expert panel. Results: Five educational modules were developed based on the HBM: know your mouth; diabetes and oral health; checking your mouth; practice good oral self-care; and choose the right tools. These modules were incorporated into the DiaOral website prototype. Eight experts representing dentistry, dental hygiene, nursing, diabetes education, and medicine rated the prototype highly on a 1–5 scale (accuracy 4.80; feasibility 4.84; acceptability 4.75; problem relevance 4.95), supporting strong preliminary content validity in expert rating. Conclusions: DiaOral website prototype was developed following a four-step, HBM-guided design approach. Multidisciplinary expert evaluation established preliminary content validity. Feasibility and acceptability of the DiaOral prototype were assessed through expert ratings. Next steps include refining DiaOral and testing its efficacy in clinical trials among PWD.