To test the effectiveness of The GOOD Life 135 eligible lower secondary public schools in the Region of Southern Denmark were invited to be enrolled in a cluster-randomised controlled trial. Between February 2015 and August 2016 schools were randomly allocated to either intervention or control group. Pupils in grade 8 and 9 from 38 schools were invited to participate in the study, and written consents from parents were obtained. Data were collected via confidential online surveys before the intervention and three months after baseline. The intervention schools received the intervention after the first survey and the control schools after the second survey. The GOOD life intervention provided normative feedback tailored for each grade at participating schools (n=38). Participating pupils (n=1355) accessed the questionnaire by self-registration on the survey website. The questionnaires measured pupils’ lifetime and last 30 days AOD use and approval of use as well as the perceived frequency of AOD use and approval of use among peers of their own grade. The primary outcome measures were overestimation of lifetime binge drinking among peers, binge drinking and two or more alcohol-related harms. Also, the baseline questionnaire covered demographic information on age, grade, sex and family affluence. In the 3-months follow-up survey, pupils in the intervention group (n=641) were asked about their satisfaction with and their recollection of the intervention. All associations with the primary outcomes were examined using multilevel logistic regression models with school-level included as random effect.
The study found that pupils´ perceptions regarding peers’ behaviour and approval were significantly higher than pupils´ actual behaviour and approval. Further, the results showed a significantly increased risk of personal alcohol use for pupils that overestimated their peers´ alcohol use and for pupils that perceived peers to approve of alcohol use. The effect evaluation revealed that pupils exposed to the intervention were less likely to overestimate lifetime binge drinking among peers compared to those in the control group (OR: 0.52, 95%CI: 0.33-0.83). They were also less likely to report alcohol-related harms (OR: 0.59, 95%CI: 0.37-0.93). No significant effect of the intervention was found for frequent binge drinking (4 or more times during the last 30 days) in the whole group. However, among pupils who, at baseline, expressed a motivation to drink more alcohol in the future (n=296), the intervention also had a preventive effect on frequent binge drinking (OR: 0.37; 95%CI: 0.15-0.95). The analyses regarding the different implementation parameters showed that higher levels of exposure to as well as better retention of the social norms messages enhanced the intervention effect for all three outcomes.
The study showed that pupils’ exaggerated perceptions regarding their peers´ use and approval of alcohol use were related to personal experience with alcohol. The findings suggested that the social norms approach could be a suitable preventive strategy for reducing harmful alcohol use among Danish adolescents. In addition, we found that increased exposure and retention of the intervention enhanced the intervention effect. Furthermore, a promising approach would be to include various intervention components that supports pupils’ comprehension of the intervention.
Papers on the design and effect of The GOOD Life
Stock, C., Vallentin-Holbech, L., & Rasmussen, B. M. (2016). The GOOD life: Study protocol for a social norms intervention to reduce alcohol and other drug use among Danish adolescents. BMC Public Health, 15, 704. doi:10.1186/s12889-016-3333-1
Vallentin-Holbech, L., Rasmussen, B. M., & Stock, C. (2017). Are perceptions of social norms regarding peer alcohol and other drug use associated with personal use in Danish adolescents? Scandinavian Journal of Public Health, 0(0). doi:10.1177/1403494817724313
Vallentin-Holbech, L., Rasmussen, B. M., & Stock, C. (2017). How effective is a Danish social norms intervention in reducing pupils alcohol perceptions and use? European Journal of Public Health, 27 (suppl 3). doi:10.1093/eurpub/ckx187.476
Stock, C., Vallentin-Holbech, L. & Rasmussen, B.M. (2017).What kind of social norms messages work in adolescents? Lessons learned from The GOOD life program., 27 (suppl 3), doi:10.1093/eurpub/ckx187.480
Vallentin-Holbech, L. (2018). The GOOD Life - A social norms intervention to reduce alcohol use and its harmful consequences among Danish adolescents. PhD-thesis. Esbjerg, University of Southern Denmark,ISBN: 978-87-91245-28-2