Journal of Substance Use, cilt.30, sa.6, ss.880-887, 2025 (SSCI, Scopus)
Background: The aim of this study was to identify how transtheoretical model-based motivational interviewing affects self-efficacy and belief perception in individuals with substance use disorder. Methods: The study was conducted between October 2021 and July 2022 using an experimental research model with pretest and posttest control group. The sample size was calculated using the G*Power 3.1.7 programme, and a total of 46 participants including 23 in the experimental group and 23 in the control group were included in the study. The data were collected using a Socio-demographic Characteristics Questionnaire prepared by the researcher, Self-Efficacy Scale (SES), and Beliefs about Substance Use Scale (BSU). Results: While the self-efficacy total mean score of the experimental group was 83.39 ± 13.13 before the experimental, it increased to 91.43 ± 11.17 after the experimental and a statistically significant difference was found between them (p <.05). BSU total mean score of the experimental group was 42.30 ± 22.42 before the experimental and significantly decreased to 25.52 ± 7.56 after the experimental, and a statistically significant difference was established between them (p <.05). Conclusion: This method was found to be effective in changing individuals’ self-efficacy and beliefs about quitting substances.