Theories of health protective behaviour offer an appealing framework in which to interpret differences in compliant and non-compliant parents with respect to childhood vaccinations [8] . While several models have been developed to account for people's adoption of health protective behaviour such as the Theory of Reasoned Action [9] , the Triandis Model [10] , Multi-Attribute Utility (MAU) Theory [11] and the Subjective Expected Utility Theory [8] , the Health Belief Model is possibly the simplest and the most widely used and tested [12, 13] . The four elements of the Health Belief Model are: perceived susceptibility (likelihood of getting the disease), perceived severity (perception of how serious an outcome or consequence is from the disease), perceived benefits (efficacy of preventive action undertaken) and perceived barriers (time, effort, money, inconvenience, pain, side effects of preventive action) [12, 13] .