@article{10272/27675,
year = {2025},
url = {https://hdl.handle.net/10272/27675},
abstract = {Simultaneous alcohol and cannabis use (SAC) poses greater health risks than using each substance separately or concurrently. This two-wave prospective study examined (1) the Theory of Planned Behavior (TPB) capacity to explain the frequency of avoiding SAC use; (2) whether adding past behavior and habit strength—non-deliberative processes—improved prediction; and (3) model invariance across sex and college status. A community sample of 378 young adults (60.3% men, Mage = 21.02, SD = 2.12) completed baseline and 3-month follow-up questionnaires. The TPB explained 55.9% of the variance in intention  and 31.4% in behavior. Adding habit strength and past behavior raised explained variance to 73.6% and 49.9%. These non-deliberative factors were the strongest predictors, reducing the effect of traditional TPB components. The model’s predictive capacity was invariant across gender and educational status. While the TPB provides a strong framework for understanding health-promoting behaviors, our results highlight the importance of considering both automatic and reasoned processes.},
organization = {Funding for open access publishing: Universidad de Huelva/CBUA This work was funded by the Agencia Estatal de Investigación (Ministerio de Ciencia, Innovación y Universidades, Spain; MICIU/AEI//10.13039/501100011033/) under grant number PID2020-118229RB-I00 granted to Fermín Fernández Calderón.},
publisher = {Springer},
title = {Explaining Avoidance of Simultaneous Alcohol and Cannabis Use: An Extended Theory of Planned Behavior Model Including Non‑deliberative Processes},
doi = {10.1007/s11469-025-01567-2},
author = {Valle del Vera, Belén and Parrado González, Alberto and Carmona Márquez, José and Fernández Calderón, Fermín},
}