<![CDATA[Background: Booster immunization with DPT-HB-Hib 4, MR dose 2, and Polio 4 maintains children's immunity after the basic series, yet coverage in several Indonesian regions remains below target. Objective: This study analysed the association of maternal knowledge and attitude with the completeness of booster immunization in children aged 24 to 36 months in Banjar Village, Pandeglang Regency. Methods: A cross-sectional study was conducted on 70 mothers selected by consecutive sampling. Knowledge and attitude were measured using validated questionnaires (r = 0.389 to 0.768; Cronbach’s alpha 0.842 and 0.876), and immunization status was verified from the Maternal and Child Health book. Data were analysed using Chi-square, Fisher’s exact test, and binary logistic regression; associations are reported as prevalence ratio (PR) and adjusted odds ratio (aOR) with 95% confidence intervals (CI). Results: Complete booster immunization was found in 52 children (74.3%). Good maternal knowledge (PR = 5.17; 95% CI 1.45 to 18.41; risk difference 69.5%) and a positive maternal attitude (PR = 1.89; 95% CI 1.36 to 2.62; risk difference 45.7%) were both associated with completeness (p < 0.001). In practice, one additional child completed booster immunization for every two mothers with good knowledge. Both persisted after adjustment for maternal age, education, and occupation (aOR 24.6 and 26.1; p < 0.01). Conclusion: Maternal knowledge and attitude are significantly associated with booster immunization completeness, so strengthening maternal health literacy should be a priority for immunization programmes at primary care level.]]>
