Heavy alcohol use among adolescents continues to be a great public health concern in most Western countries, given the immediate and long-term health consequences [1
]. In the Netherlands, the prevalence of heavy drinking is particularly high among adolescents with a low educational background, aged 15 to 20
Adolescents with a low educational background not only engage in heavy drinking more often, but also start drinking at a younger age compared to higher educated peers [4
]. Possible explanations for this difference are that they spend more time with friends, are raised more often in single-parent families, experience less rule setting and monitoring by the mother, and engage more often in externalizing behaviors [3
Both early drinking onset and heavy drinking can place low-educated adolescents at an increased risk for developing acute and long-term health consequences, such as alcohol-related violence [7
], drunk driving, injuries and risky sexual behavior [8
]. This behavior is also associated with brain impairment and neurocognitive deficits, which have implications for learning and intellectual development [9
]. In the long term, heavy drinking is predictive of, among other things, problematic adult alcohol use [11
], liver cirrhosis [12
], specific types of cancer, and cardiovascular disease [1
]. From a public health viewpoint, it is crucial to develop alcohol prevention programs directed at adolescents with lower education levels to encourage them to change their risky drinking practices, especially considering that 60% of all adolescents, following secondary education in the Netherlands, are low-educated [3
]. The study described in this protocol will test the effectiveness of the WDYD web-based brief alcohol intervention that aims to reduce alcohol use among heavy-drinking adolescents aged 15 to 20
years with a low educational background.
The school system in the Netherlands comprises several types of education. After eight years of primary education, pupils go directly to secondary education, which consists of preparatory secondary vocational education (VMBO), senior general education (HAVO), and preuniversity education (VWO). Pupils with a VMBO diploma are able to attend a secondary vocational education (MBO), which has four learning routes: 1) the theoretical route allowing admission to MBO or HAVO, 2) a mixed educational route, 3) the vocationally oriented route, and 4) a vocational route allowing pupils to enter the labor market directly. HAVO prepares pupils for higher professional education (HBO), while VWO prepares pupils for university.
In the Netherlands, there is a lack of evidence-based alcohol prevention programs targeting adolescents following the lower education levels [13
]. The existing programs are mainly concentrated on first- and second-year MBO pupils, while less attention is paid to third- and fourth-year MBO pupils, partly due to the increasing difficulty of reaching them as a consequence of their internship commitments [14
]. Moreover, the prevention programs are inadequately tuned to the influence of the direct social environment (that is, friends, peers and parents) that is related to the heavy drinking patterns of this specific target group [3
]. Therefore, it is essential to develop and evaluate the effectiveness of alcohol prevention programs aimed at adolescents following the lower education levels.
Prior research has demonstrated that web-based brief alcohol interventions can be effective in reducing heavy alcohol use in adolescents and students [15
]. Interventions delivered electronically via the internet have large practical advantages compared to the more conventional methods [22
]. The internet is easily accessible and particularly appealing to young people. Furthermore, it allows the participants to access the intervention in the privacy of their homes at a convenient time, which may enhance their feelings of anonymity. Brief interventions are especially easy to implement by creating links on websites or providing the link of this website in promotion and education materials. Moreover, these interventions can be provided in an automated, cost-effective and flexible way [25
]. Finally, the majority of adolescents in Western countries have access to the internet and make frequent use of internet technologies [26
], which make web-based brief alcohol interventions particularly suitable for our target group.
Objectives and hypotheses
The objective of the study described in this protocol is to evaluate the effectiveness of the What Do You Drink web-based brief alcohol intervention among heavy-drinking adolescents aged 15 to 20
years with a low educational background. A two-arm parallel-group randomized controlled trial will be conducted with two follow-up assessments (that is, after one and six months) to examine the effectiveness of the intervention. Two hypotheses will be tested. First, we expect that a larger percentage of participants in the experimental condition will drink within the normative limits of the Dutch National Health Council for low-risk drinking [28
] when compared to the control condition as a result of the WDYD intervention. This means that participants’ consumption will not exceed a mean heavy alcohol use consumption of more than seven (girls aged 15 to 16
years), twelve (boys aged 15 to 16
years), fourteen (women aged 17 to 20
years) or twenty-one (men aged 17 to 20
years) glasses of standard units of alcohol per week and/or, in the case of binge drinking, five or more glasses of standard units of alcohol on one drinking occasion at least once per month and week for boys and girls aged 15 to 16
years and men and women aged 17 to 20
years, respectively, at one month and six months after the intervention. Second, we expect that participants in the experimental condition will reduce their mean weekly alcohol consumption and frequency of binge drinking. Thus, it is hypothesized that exposure to the WDYD intervention will be more effective compared to no intervention.