Efficacy of ready4life: a digital addiction prevention program for young people

INTERVENTION: Participants will be cluster‐randomised, using school class as a randomisation unit. Due to the heterogeneity of students in the different vocational schools, we will use a separate randomisation list for each school (stratified randomisation). Furthermore, to approximate equality of sample sizes in the study groups, we will use block randomisation with computer‐generated randomly permuted blocks of 4 cases. School classes will be randomised into two groups, an intervention and a control group. Research assistants supervising the baseline and follow‐up assessments will be blinded to the group allocation of the participants. Participants in the intervention group will participate in the digital prevention program "ready4life". Within this app‐based program, an individual profile is generated on the basis of a survey conducted via smartphone. This profile shows areas in which a participant has sufficient resources and in which there is a need for coaching or counselling. Based on their risk and resource profile, the participants can select two out of the following 6 program modules: stress, social skills, Internet use, tobacco, cannabis, and alcohol. Participants of the intervention group will receive indivdualised coaching for a period of four months by a conversational agent (chatbot). This virtual coach motivates the participants to deal sensitively with addictive substances, gives feedback on current consumption and provides information in weekly dialogues. In a separate chat within the app, the participants can pose personal questions to regional addiction prevention experts. In order to achieve high engagement rates, interactive elements such as quiz questions, contests, and a playful competition are integrated into ready4life. CONDITION: Prevention of addictive behaviors in students ; Mental and Behavioural Disorders PRIMARY OUTCOME: ; At baseline‐ and 6‐months follow‐up, measured by self‐report:; A composite measure for addictive behaviors composed of:; 1. At risk‐drinking in the preceding 30 days, according to guidelines of the Swiss Federal Office of Public Health; 2. 30‐days point prevalence for tobacco/e‐cigarette smoking; 3. 30‐days point prevalence for cannabis use; 4. Problematic Internet use assessed by the Compulsive Internet Use Scale, CIUS; ; SECONDARY OUTCOME: ; At baseline‐ and 6‐months follow‐up assessments:; 1. General self‐efficacy assessed by the Short Scale for Measuring General Self‐efficacy Beliefs (ASKU); 2. Stress assessed by a single‐item measure of stress symptoms; INCLUSION CRITERIA: 1. Vocational school student 2. Minimum age 15 3. Possession of a smartphone