App-Based Coaching to Prevent Addictive Behaviors in Vocational School Students: A Cluster Randomized Trial

Diana Guertler; Hannah Schmidt; Merten Neumann; Dominique Brandt; Arne Dreißigacker; Dominic Bläsing; Anne Möhring; Christian Meyer; Anja Bischof; Gallus Bischof; Svenja Sürig; Florian Rehbein; Lisa Hohls; Stefan Borgwardt; Susanne Wurm; Severin Haug; Hans-Jürgen Rumpf

doi:10.1016/j.jadohealth.2024.11.010

App-Based Coaching to Prevent Addictive Behaviors in Vocational School Students: A Cluster Randomized Trial

J Adolesc Health. 2025 Mar;76(3):499-508. doi: 10.1016/j.jadohealth.2024.11.010. Epub 2025 Jan 17.

Authors

Diana Guertler¹, Hannah Schmidt², Merten Neumann³, Dominique Brandt², Arne Dreißigacker³, Dominic Bläsing⁴, Anne Möhring⁵, Christian Meyer⁶, Anja Bischof², Gallus Bischof², Svenja Sürig², Florian Rehbein⁷, Lisa Hohls², Stefan Borgwardt², Susanne Wurm⁶, Severin Haug⁸, Hans-Jürgen Rumpf²

Affiliations

¹ Department of Prevention Research and Social Medicine, Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany; DZHK (German Centre for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany; Department of Methods in Community Medicine, Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany. Electronic address: diana.guertler@med.uni-greifswald.de.
² Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, Germany.
³ Criminological Research Institute of Lower Saxony (KFN), Hannover, Germany.
⁴ Helmholtz Institute for One Health, Greifswald, Germany.
⁵ Department of Methods in Community Medicine, Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany.
⁶ Department of Prevention Research and Social Medicine, Institute for Community Medicine, University Medicine Greifswald, Greifswald, Germany.
⁷ Department of Social Work, FH Münster University of Applied Sciences, Muenster, Germany.
⁸ Swiss Research Institute for Public Health and Addiction, University of Zurich, Zurich, Switzerland.

PMID: 39818651
DOI: 10.1016/j.jadohealth.2024.11.010

Abstract

Purpose: This two-arm cluster randomized controlled trial evaluated the effectiveness of an app-based addiction prevention program in German vocational school students.

Methods: Schools from 5 German federal states were recruited. No eligibility criteria for classes were applied; enrollment decisions were made by school heads or teachers. Students were eligible if aged at least 16 years and possessing a smartphone (participation rate: 46.7%). Classes were randomly allocated to intervention or control within blocks of 4, stratified by school. Intervention classes received app-based coaching for 16 weeks. Control classes received health information and could access the coaching after 12 months. Both groups were assessed at baseline, 6 months, 6 and 12 months (follow-up rates: 35.8% and 34.9%). Primary outcomes were changes in alcohol, tobacco, cannabis consumption, and problematic Internet use at the individual level. Participants were blinded to group allocation until providing informed consent; the primary outcome analyst was also blinded. Generalized linear models with multiple imputation were used across all time points.

Results: Intention-to-treat analyses of 1,266 intervention and 1,279 control participants from 162 classes each showed small but significant effects on social competence (b = 0.075, confidence interval [CI] 0.027, 0.123; d_6-months = 0.10; d_12-months = 0.19), stress (b = -0.02, [CI -0.03, -0.01]; d_6-months = -0.10; d_12-months = -0.20), problematic Internet use (b = -0.058, [CI -0.098, -0.019]; d_6-months = -0.08; d_12-months = -0.17), and tobacco consumption (b = -0.031, [CI -0.053, -0.009]).

Discussion: App-based programs can reduce addictive behaviors and enhance life skills among vocational students, fostering broader mental health benefits.

Keywords: Addiction; Adolescents; Gaming; Mobile app; Prevention; Social competence; Social media; Substance use; Vocational students; Young adults.

Publication types

Randomized Controlled Trial

MeSH terms

Adolescent
Behavior, Addictive* / prevention & control
Female
Germany
Humans
Male
Mentoring* / methods
Mobile Applications*
School Health Services
Schools
Students* / psychology
Vocational Education*