Validation of Health Belief Model and Theory of Planned Behaviour Constructs for Predicting Malaria Vaccine Acceptance in Ghana: A Partial Least Squares Structural Equation Modelling Approach

Aim:

This study examines the predictive power of constructs from the Health Belief Model (HBM) and Theory of Planned Behaviour (TPB) in explaining malaria vaccine acceptance in Ghana in the post-COVID-19 era, while also assessing the reliability of these constructs within this context.
 
Methods:

A cross-sectional survey of 622 adults was conducted in two Ghanaian municipalities representing high- and low-malaria endemicity. Constructs from HBM and TPB, alongside contextual factors such as religiosity and traditional medicine use, were measured. Partial Least Squares Structural Equation Modelling (PLS-SEM) was used to assess construct validity and estimate their predictive relationships with vaccine intention.

Results:

All constructs demonstrated strong reliability (Cronbach’s α = 0.894–0.985) and convergent validity (AVE = 0.797–0.971). The model demonstrated strong predictive power, explaining 67.6% of the variance in vaccine intentions (R² = 0.676). Attitudes (β = 0.578, p < 0.001) and perceived benefits (β = 0.531, p < 0.001) were the strongest predictors of acceptance. Perceived behavioural control had a marginal effect (β = 0.124, p = 0.064). Perceived disease vulnerability negatively predicted intention (β = -0.330, p = 0.006), while perceived severity and subjective norms were non-significant.

Conclusion:

HBM and TPB constructs are reliable and valid in predicting malaria vaccine acceptance in Ghana. Interventions should focus on strengthening positive attitudes and highlighting the benefits of vaccination, while addressing misconceptions among those who perceive themselves as most vulnerable. This study provides novel evidence on malaria vaccine acceptance in a post-pandemic context and underscores the utility of combining HBM and TPB for predicting preventive health behaviours in sub-Saharan Africa.