Background: Much research has assessed the relationship between psychosocial constructs and intentions to engage in protective health behaviors. However, few studies consider the additional relationship of such intention on the ultimate adoption of a behavior. Research has presumed, rather than actually modeled, the additional effect between intention and final behavior.
Objectives: To model the relationship between theory-based health beliefs towards Hepatitis B virus (HBV) vaccination, intention to be vaccinated, and first dose uptake of vaccine.
Methods: 830 predominantly African-American (83%) men (n=522) and women (n=308) aged 18-75 who attended urban STD clinics were recruited to participate in a study assessing acceptance of HBV vaccine. Theory-based health beliefs, attitudes towards HBV vaccination, and intention to be vaccinated were assessed. Subsequently, participants were offered the first dose of vaccine. Relationships of health beliefs and intention to first dose uptake of HBV vaccine were analyzed with structural equation modeling, using full information maximum likelihood estimation, in AMOS, 16.0.
Results: Of the 830 participants, 444 (54%) accepted the first dose of vaccine. Controlling for the influence of fear of vaccines, fear of shots, perceived severity of, and susceptibility to HBV, normative beliefs, and obstacles to vaccination, intention to receive the vaccine significantly predicted (B = 0.746,p<.000) dose one acceptance. Model fit indices suggest excellent fit of the model to the data.
Conclusions: These findings provide support for a theory-based model of HBV vaccine acceptance where intention independently and strongly predicts behavior, when the opportunity to adopt the behavior is presented in close proximity with the elicitation of health beliefs regarding vaccination.
Implications for Programs, Policy, and/or Research: These findings support the role of theory in health behavior research, and suggest that messaging designed to promote intention to get vaccinated, combined with immediate opportunity to receive the vaccination, may substantially improve vaccine uptake.