CFIR-guided formative implementation research to co-design a supervised toothbrushing programme through Anganwadi centres in Kerala, India

Dental caries remains a major public health concern among preschool children, driven by modifiable behaviours such as inadequate toothbrushing and poor oral health practices. Anganwadi Centres are community-based centres within India’s Integrated Child Development Services (ICDS) system that provide preschool education, nutrition, and child health-related services. Anganwadi workers, who routinely interact with preschool children and families, represent a potentially accessible workforce for delivering preventive oral health interventions. This study aimed to identify implementation determinants and co-design a contextually adapted supervised toothbrushing programme (Model 0) using CFIR and ERIC frameworks. A formative mixed-methods study using a convergent parallel design was conducted among 168 Anganwadi workers and helpers in Nilambur Block, Malappuram district, Kerala. Quantitative data were collected using a validated questionnaire assessing knowledge, beliefs, confidence, and current practices related to oral health. Qualitative data were obtained through in-depth interviews with multi-level stakeholders and analysed thematically, followed by integration using a convergence coding matrix and CFIR mapping to inform intervention design. A Total 94.0% of participants had no prior oral health training, with identified gaps in fluoride knowledge (69.6%) and low confidence in providing oral health education (94.6%). Despite these deficits, participants showed a strong motivation and perceived relevance of oral health promotion. Qualitative findings identified multilevel barriers including lack of training, workload constraints, limited policy prioritisation, and community-level practices, alongside facilitators such as structured routines, existing infrastructure, and stakeholder support. These integrated findings informed the development of a six-component CFIR-informed Model 0 implementation blueprint. The study identified that even- though motivational readiness exists within the ICDS system, implementation is constrained by capability gaps and structural limitations across CFIR domains. The co-designed Model 0 provides a theory-informed, contextually adapted implementation strategy that aligns with existing systems and addresses key determinants through training, workflow integration, community engagement, and governance mechanisms.