The Effectiveness of Motivational Interviewing in Preventing Early Childhood Caries: A Cluster Randomised Controlled Trial Among Mothers of Infants in Terengganu.

This study will be conducted in Ministry of Health (MOH) Maternal and Child Health Clinics (MCHCs) and MOH dental clinics in Setiu and Hulu Terengganu, selected for their similar sociodemographic characteristics. A two-arm, parallel cluster-randomized controlled trial (1:1 allocation) will be implemented, where the study group receives Anticipatory Guidance (AG) through Motivational Interviewing (MI), and the control group receives conventional MOH AG.

Mothers aged ≥18 years who can understand Bahasa Malaysia and their healthy 6-month-old infants (full-term, without congenital conditions) are eligible. Mothers with postpartum depression and infants requiring special oral healthcare are excluded. A total of 228 mother-infant pairs will be recruited using multistage sampling. Three MCHCs from Setiu and three randomly selected MCHCs from Hulu Terengganu will participate. Systematic sampling will be applied within each clinic.

Data collection occurs at infant ages 6, 9, and 12 months during routine immunization visits. At each visit, infants undergo oral examination using ICDAS and a caries risk assessment. Mothers complete age-specific validated questionnaires on knowledge and practices. The study group receives two MI sessions (at 6 and 9 months) with follow-up phone calls, while the control group receives routine AG by MOH staff.

The MI protocol will be developed based on established MI frameworks and be validated through expert review, will be pretested among mothers and dental officers/therapists in MOH MCHC and MOH dental clinic in Besut district. While fidelity assessment of MI sessions conducted will be done using MITI 4.2.1 guidelines. All MI sessions will be delivered by the trained principal investigator. Approximately 8 minutes are required for infant oral examination, 7 minutes for questionnaire completion, and 30 minutes for MI.

Data will be analysed using descriptive statistics, paired t-tests, independent t-tests, McNemar's test, and Chi-Square test with significance set at p < 0.05.

Ethical approval was obtained from Jawatankuasa Etika Penyelidikan Manusia USM (JEPeM)/ Human Research Ethics Committee USM (HREC) and Medical Research and Ethics Committee (MREC) MOH. Participation is voluntary, with confidentiality ensured. No major risks are expected.