METHODS: A qualitative study design involving individual both face-to-face and online in-depth interview was used. The topic guide was developed from the Health Belief Model theoretical framework. Seven face-to-face and seven online interviews were conducted with parents in the Klang Valley (an urban area) who had refused childhood vaccination. All interviews were audio-recorded, transcribed verbatim and checked. Thematic approach was used to analyze the data. Data was collected until data saturation was reached.

RESULTS: Findings were summarized into two main categories: Personal Health Beliefs and Vaccine Related Concerns. Six personal health beliefs were identified: lack of confidence in modern medicine and health care personnel, pharmaceutical conspiracy to sell medicines, preference to a natural approach to health, personal instincts, religious beliefs and having a partner with similar beliefs. Four main vaccine-related concerns were identified: negative effects and content concerns, doubts of necessity and lack of information and knowledge regarding vaccines. Parents recommended that more empathy from healthcare professionals and evidence on safety and content purity would help them reconsider vaccination.

OBJECTIVES: To assess the test-retest reliability of the Parent Attitudes about Childhood Vaccines (PACV) questionnaire in Malay language; to determine the prevalence of vaccine hesitancy among parents and its associations with parents' socio-demographic characteristics.

METHODS: Forward and backward translation of PACV in Malay language was carried out. The reliability of the Malay-PACV questionnaire was tested among parents with children. The same questionnaire was used to study vaccine hesitancy among parents in a tertiary hospital in Kuala Lumpur. Information pertaining to socio-demographic characteristics, sources of information regarding vaccination and vaccine hesitancy were collected. Associations between vaccine hesitancy with socio-demographic factors were tested using Multivariable Logistic Regression.

RESULTS: The Spearman correlation coefficient and Cronbach alpha for total PACV was 0.79 (p<0.001) and 0.79 respectively. The intra-class correlation coefficients of the subscales ranged from 0.54 to 0.90 demonstrating fair to excellent reliability. A total of 63 (11.6%) parents were noted to be vaccine hesitant. In the univariate analyses, vaccine hesitancy was associated with unemployed parents, parents who were younger, had fewer children and non-Muslim. In the multivariate model, pregnant mothers expecting their first child were four times more likely to be vaccine hesitant compared to those who already had one or more children (aOR: 3.91, 95% CI: 1.74-8.79) and unemployed parents were also more likely to be vaccine hesitant (aOR: 1.97, 95% CI: 1.08-3.59). The internet (65.6%) was the main source of information on vaccination followed by brochures (56.9%).