Background: Excessive alcohol and other substance use in adolescence is prevalent and has developmental consequences that extend into adulthood. In parallel with other public health and clinical measures, early identification in primary care represents an important step to address this problem. Screening and brief intervention by primary care physicians is recommended but often fails to be implemented due to time constraints and other barriers. Working hypothesis: Recent evidence suggests that simply asking individuals about their substance use may in itself encourage behaviour change, regardless of the clinical intervention that may follow. This hypothesis has not as yet been tested in a population of young people consulting in primary care. The investigators hypothesise that inviting young people to complete a brief substance use screening questionnaire in the waiting room before their primary care consultation has the potential to lead to a decrease in substance use in the months following this consultation.

Specific aims: The aim of this pilot project is to develop and test the methods for a future randomized trial. The future trial will assess the effectiveness of pre-consultation substance use screening, compared to screening for other behaviors, on subsequent substance use in young people between the ages of 15 and 24 years consulting primary care physicians.

Expected value of the proposed project: The clinical context of primary care has the potential to trigger behavior change in young people, thus favoring improved adult outcomes in this population. If effective, pre-consultation substance use screening could contribute to a reduction in excessive substance use among young people in a simple and cost-effective way. This pilot study will provide precious feasibility data for the design of the related cluster randomised trial.

Background:

Excessive alcohol and other substance use in adolescence has short and long term consequences on health and contributes extensively to lifelong morbidity. Since prevalence of this excessive use is high among young people consulting in primary care, primary care physicians (PCPs) are well placed to address this problem. PCPs are encouraged to screen and provide brief interventions addressing excessive substance use in young people, but a range of barriers, such as time constraints and insufficient training, limits the implementation of these recommendations in primary care practices. Several recent trials of brief primary care interventions showed substantial reductions in the proportion of participants who were excessive substance users at follow-up (20% to 30% reductions), but no statistically significant differences between the intervention and control groups. Reductions in substance use in the control group can be due to several factors: 1) Regression to the mean (repeat participant responses show a trend towards the mean values for the participating population), 2) Research participation effects (e.g. Hawthorne effect, social desirability bias), 3) Historical trends which affect the entire population, such as reductions in per capita alcohol use in relation to public health measures, 4) Assessment reactivity, when pre-intervention assessment itself encourages behavior change and thus serves as an intervention. In a randomized design these factors should apply equally to both groups, and additional effects of the tested intervention may still be visible. If reductions in substance use at follow-up are due to assessment reactivity, this suggests screening in the clinical context could act as an intervention in itself and be as effective as a brief intervention within the consultation. To date this hypothesis has not been explored in a population of young people attending primary care.

Aim of the Trial:

To assess the effectiveness of simply screening participants for excessive substance use before the consultation in the waiting room in reducing the prevalence of excessive substance use in young people attending primary care.

Objectives of the pilot study:

1. To pilot all methods for a randomized trial of the substance use screening intervention (patient recruitment, intervention and control conditions, follow-up procedures),
2. To obtain feedback from PCPs and patients in relation to the feasibility and acceptability of the proposed methods for the trial.

Methods:

The intervention screening questionnaire will be based on an instrument developed for previous trials. Questions for the control condition (about physical activity) will be based on a validated physical activity questionnaire (International Physical Activity Questionnaire, IPAQ). As recommended in guidelines for adolescent health and primary care research, both young people and PCPs will be involved in the development of the screening tools. A reference group of young people and of PCPs will be established in order to benefit from their input into the design of the study.

The intended trial procedure including recruitment of young people, screening for health risk behaviours and follow-up will be piloted in 6 primary care practices in the canton of Geneva in order to inform the final design of the trial.

The physicians involved in the advisory-group will be invited to undertake the pilot study in their own practices. They will be asked to include a minimum of five patients each. Patients will be randomized to either the intervention or the control questionnaire.

Patients will be recruited using a similar procedure as the one developed for one of our previous studies, the PRISM-Ado trial. Prior to the consultation, eligible patients will be invited by the practice assistant to participate in the study. Participants will be given an information and consent form, and will be given the choice to complete the study questionnaire either online (using a QR code to access the questionnaire on their phone) or in a paper format, in the waiting room. Participants will be asked to provide a contact phone number (mobile phone) to allow follow-up assessments 1 month following the consultation. Young people involved in the PRISM-Ado study underlined that they would be less likely to respond honestly to a screening questionnaire if it were to be used by the doctor in the consultation. Therefore this pre-consultation questionnaire will be entirely anonymous and will not be available for the PCPs to help them identify at-risk consumers. Written informed consent will be obtained from all young people before they complete the screening survey. Patient questionnaires will be coded to ensure anonymity.

A meeting of participating doctors will be organized to receive feed-back on all aspects of the study. Participating patients will be asked to provide their contact details (mobile phone number) so that they may be contacted to provide feed-back on the screening questionnaire and study procedure.

Physicians' and young people's characteristics will be summarized using frequencies for categorical data and means and standard deviations for continuous data. This summary will provide us with an initial profile of youth consulting in the practices and will inform planning and sample size calculations for the randomized trial. Participant feed-back will be summarized in a qualitative way.

Importance of the expected results:

The results of this pilot study will provide precious information for the final design of the randomised trial in primary care. These results will be published in a medical journal and presented at medical conferences. The consequences of excessive substance use in adolescence extend into adulthood. The investigators are hopeful that the interventions developed and piloted in this project will provide new ways of ensuring better health for young people today and in the future.

Inclusion Criteria:

• Patients consulting at the participating primary care practice during the recruitment period (2 months).

Exclusion Criteria:

• Acute illness requiring immediate attention of the physician
• Severe mental health conditions requiring treatment in a specialized setting
• Inability to read the trial information in French
• Person not consulting as a patient (e.g. parent of a child consulting a pediatrician, accompanying friend or partner).

We do not plan to make individual participant data available for this feasibility study for data protection reasons, because there will be a very limited number of participants.

Participants: Although they cannot be masked to the content of the intervention (questionnaire), they are only informed that the study is about health behaviours in general. Thus, they are masked as to whether they are in the intervention or control group.

Care provider: As they cannot have access to the participants' questionnaires, they are masked.