Survey on determinants of intention to reduce nasopharyngeal cancer risk: an application of the theory of planned behavior

Background: To have better prognostic outcomes and minimize deaths due to nasopharyngeal cancer, it is vital to understand factors that motivate the public to undertake cancer preventive measures. The study investigated deter‑ minants of intention to adopt measures to reduce nasopharyngeal cancer risk using the Theory of Planned Behavior. Method: A cross-sectional survey was conducted on Malaysians (n=515) using a questionnaire on attitudes, subjective norm, perceived behavioral control, knowledge of nasopharyngeal cancer, past nasopharyngeal cancer preventive behavior, and intention to adopt preventive measures. The attitudes construct encompassed perceptions of susceptibility, severity, benefts and barriers. Hierarchical regression of mediation efect under structural equation model approach was used to test the theory. The model was re-estimated using the two-stage least square approach by instrumental approach. Next the Maximum Likelihood Estimation-Structural Equation Modeling was conducted to gauge the instrumentation and check the robustness of the model’s simultaneity. Results: The respondents had moderate knowledge of nasopharyngeal cancer, and reported high levels of perceived risk, perceived severity and perceived behavioral control. The respondents were under little social pressure (subjec‑ tive norm) to perform nasopharyngeal cancer preventive actions, marginally believed in the benefts of medical tests and reported few barriers. The Partial Least Squares-Structural Equation Modeling results show that the relationship between intention and four independent variables were signifcant (perceived behavioral control, perceived risk, per‑ ceived severity, marital status) at p<.05. Tests of Two-stage Least Square Approach and Maximum Likelihood Estima‑ tion-Structural Equation Modeling confrm the four key factors in determining the intention to reduce nasopharyn‑ geal cancer risk. The variance explained by these factors is 33.01 and 32.73% using Two-stage Least Square Approach and Maximum Likelihood Estimation-Structural Equation Modeling respectively. Intention to undertake nasopharyn‑ geal cancer risk-reducing behavior has no signifcant relationship with subjective norm, attitudes (perceived benefts and barriers to screening), knowledge of nasopharyngeal cancer and past behavior in enacting nasopharyngeal cancer preventive measures. The only demographic variable that afects intention is marital status. Gender, age, race, religion, education level, and income are not signifcantly associated with intention