Extending the theory of planned behavior in green purchasing: Exploring the mechanisms of attitude, subjective norms, and perceived behavioral control influence on green purchase behavior of consumers

Abstract

In recent years, the green consumption model has emerged as a new approach gaining global popularity due to its ability to address the limitations of traditional consumption models by focusing on environmental protection and ecosystem preservation in the face of severe damage. In Vietnam, green consumption has become a growing trend, driven by Vietnamese consumers’ increasing concern about environmental and health issues. In this regard, researchers, lawmakers, and marketers have been working continuously to investigate and clarify the elements that influence green buying. Applying the Theory of Planned Behavior (TPB; Ajzen, 1985), a model known for its powerful predictive ability regarding both intentions and actual environmentally responsible behaviors, is one notable research avenue that has attracted attention but has not been explored in sufficient depth. To fill this gap, our study proposes a model incorporating two common antecedents (Environmental Consciousness and Health Consciousness) of the TPB components (Attitude, Subjective Norms, Perceived Behavioral Control) and examines the effect of these components on consumers’ green purchase intentions (GPI) and green purchase behavior (GPB). The study applied a quantitative design, using a questionnaire developed to collect data through quota sampling, with a final sample size of 273 respondents. Using tools like SPSS 26.0, AMOS 24, and SMART-PLS 4.1.0.9, the gathered data was examined using descriptive statistics, Cronbach’s alpha reliability testing, Exploratory Factor Analysis (EFA), Pearson correlation analysis, Confirmatory Factor Analysis (CFA), and Structural Equation Modeling (SEM). The findings show that the three primary TPB components are positively impacted by environmental consciousness and health consciousness. Furthermore, positive relationships were observed between the three TPB components and Green Purchase Intentions (GPI) as well as between GPI and Green Purchase Behavior (GPB). Specifically, Perceived Behavioral Control was also confirmed to have a direct positive effect on GPB. These results contribute to both theoretical and practical perspectives by expanding the literature on consumer behavior and marketing while also helping businesses make effective marketing decisions to encourage green purchasing. However, the study faces limitations in terms of sample size, comprehensiveness, diversity, and data collection methods, paving the way for various future research directions