Childhood immunisation default rate and its associated factors among children attending public health clinics in Klang Health District, Selangor, Malaysia: A cross-sectional study

ABSTRACT

Introduction: Childhood immunisation is one of the World Health Organization’s strategies for reducing vaccine-preventable diseases (VPDs). However, a proportion of children in Malaysia remain unvaccinated, as reflected in the increasing incidence of VPDs. This study aimed to determine the childhood immunisation default rate (CIDR) and its associated factors among children in Klang District.
Methods: A cross-sectional study was conducted from July to September 2023 among parents or guardians accompanying children aged 12-24 months at selected maternal and child health clinics in Klang Health District. Systematic random sampling was used, and an assisted validated questionnaire was utilised to assess sociodemographic, immunisation and associated factors. Data were analysed using SPSS version 29, involving three-level analysis (descriptive, bivariate (chi-square and Fisher’s exact test) and multivariable logistic regression).
Results: A total of 400 respondents were recruited. The CIDR was 25.5%. The second measles, mumps and rubella (MMR) vaccine dose (22.1%) had the highest default rate, followed by the third pneumococcal vaccine dose (16.3%) and first MMR vaccine dose (14.3%). Child with younger age group (P=0.045) was found to be a risk factor, whereby healthy children (P<0.001) and having no transportation (P<0.001) were the protective factors to defaulting.
Conclusion: This study shows a high CIDR, reflecting gaps in existing policies and systems. Child’s age, health status and transportation were significantly associated with the CIDR. Therefore, more awareness and knowledge about the contraindications for immunisation and the importance of correct timing for immunisation should be emphasis. The associations between immunisations defaulting and transportation availability warrants further investigations.