Long‐term effects of a lay health advisor intervention on immigrant children’s dental caries and maternal preventive behaviour: A randomized controlled trial

Objectives An oral health disparity exists between native and immigrant children in Taiwan. This study evaluated the long‐term effectiveness of a lay health advisor (LHA) intervention on immigrant children's dental caries and maternal preventive behaviours. Methods Fifty‐one immigrant mother‐child pairs were randomly assigned to LHA intervention (n = 23) and control (n = 28) groups. Mothers in the LHA group received a four‐chapter one‐on‐one lesson plan, which included dental caries–related knowledge, brushing techniques, caries prevention and free preventive services, from the LHA over 4 weeks. Mothers in the control group received only a health brochure. Baseline and 1‐week, 2‐month, and 8‐month follow‐up information was collected using dental examinations and questionnaires. Results The mean ages of the children in the LHA and control groups were 4.0 ± 1.4 and 4.2 ± 1.5, respectively. The decayed, missing due to caries, filled teeth (dmft) index in the LHA and control groups was 4.8 ± 6.0 and 5.4 ± 5.4, respectively, at baseline. At the 8‐month postintervention follow‐up, the number of filled teeth (ft) in the LHA group was higher than that in the control group (β = 8.3, P = .033). The effect size (ES) demonstrated an upward trend at 1‐week, 2‐month and 8‐month follow‐ups in ft (ES = 0.21, 0.50 and 0.59, respectively) and a decrease in the number of decayed teeth (dt) (ES = 0.30, 0.43 and 0.57, respectively). The mothers in the LHA group were observed to be 10.9 times more likely than control mothers to assist their children in toothbrushing for 3 min at the 1‐week follow‐up (95% CI = 1.98‐59.40, P = .006). Conclusions The LHA intervention strategy had positive effects on the immigrant children's new dt and ft and on maternal preventive behaviour, such as assisting their children in toothbrushing.