Condition category
Mental and Behavioural Disorders
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Renske Spijkerman


Contact details

Montessorilaan 3
6500 HE
+31 (0)70 243 615 767

Additional identifiers

EudraCT number number

Protocol/serial number

ZonMw: 50-50130-98-101/2008

Study information

Scientific title

The effectiveness of a web-based brief alcohol intervention in reducing underage drinking and the added value of normative feedback: a three-arm randomised controlled trial


Jongeren drinktest (adolescent online drinktest)

Study hypothesis

Two hypotheses are tested:
1. An online multi-component brief alcohol intervention will encourage abstention and moderate drinking rates in 15 to 20 year-old binge drinkers
2. The inclusion of normative feedback will enhance the effectiveness of this web-based brief alcohol intervention

Ethics approval

Not provided at time of registration

Study design

Three-arm randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Alcohol abuse


The web-based brief alcohol intervention, referred to as, was developed by professionals of the Netherlands Institute of Mental Health and Addiction (Trimbos Instituut). The trial testing its effectiveness was financed by The Netherlands Organisation for Health Research (ZonMw), the Netherlands Institute of Mental Health and Addiction (Trimbos Instituut) and Radboud University Nijmegen.

Participants are randomly assigned to one of the two intervention conditions or a control condition (no intervention). In the intervention conditions, participants receive one of two versions of this web-based brief alcohol intervention, namely a version that does not include normative feedback or a version that does. Both versions of the web-based brief alcohol intervention contain two parts, i.e. a questionnaire with items addressing participants' drinking patterns, drinking motives, and health risk status, and personalised feedback based on participants’ answers to the earlier posed questions of the questionnaire including advice about moderate drinking.

The advice for young adults aged 18 - 20 years is in line with the guidelines of the Dutch National Health Council recommending that men should not drink more than 2 glasses alcohol per day and women 1 glass alcohol per day (Dutch National Health Council, 2009). Adolescents under the age of 16 receive advice to abstain from alcohol. Adolescents aged 16 - 17 years are advised to abstain from alcohol and if they drink alcohol, they are recommended to drink moderately (not more than 1 or 2 glasses per occasion). The intervention duration is approximately 10 minutes.

The feedback is tailored to participants’ age (under 16, 16 - 17 years of age, and 18+) and gender, and organised along four topics for the intervention-without normative feedback group, and five for the intervention-with normative feedback group.

The following topics are addressed:
1. Personal drinking behaviour and related health risks
2. Drinking motives and suggestions to reduce alcohol use instigated by risk-conducive motives, such as drinking to forget problems, or to conform to peer pressure
3. Risk to develop problematic alcohol use or alcohol dependence
4. Personal perceptions about own alcohol use and related risks
5. Normative feedback

The drink test with normative feedback provides additionally an overview of how much participants think their age-mates will drink, how much their age-mates actually drink and how much the participants drink themselves. This information is presented in a bar chart showing participants' own weekly alcohol use, the actual prevalence rates of Dutch adolescents' weekly alcohol use (matched according to participants' sex and age), and the prevalence rates of Dutch adolescents’ weekly alcohol use as estimated by participants. The data on peers' actual alcohol consumption levels are retrieved from alcohol prevalence estimates among same age-groups found in a nationally representative sample of high-school students (included in feedback for adolescents aged 15 - 17 years) and the general population (included in feedback for young adults aged 18 - 20 years). Only participants who overestimate their peers' alcohol consumption receive prevalence rates about their peers' actual alcohol use. If estimations are correct or lower than the actual prevalence rates, participants are informed that they provided the correct estimation.

Intervention type



Not Applicable

Drug names

Primary outcome measure

1. Weekly alcohol consumption (number of glasses per week). This measure is assessed using the Dutch version of Weekly Recall. Participants are asked to indicate retrospectively for all past 7 days, how many standard units they consumed. For example: "Yesterday it was … (fill out the name of the day) and I consumed … standard units". To ensure standardised responses, we provide for various beverages an overview of standard units.
2. Moderate drinking (0 = moderate drinking, 1 = no moderate drinking). Participants aged 15 - 17 years are labeled 'moderate drinkers' if they consumed no alcohol in the past week. Boys in the ages between 18 to 20 years are regarded as moderate drinkers if they consumed less than 14 alcoholic drinks in the past week and same-aged girls are regarded as moderate drinkers if they consumed less than 7 alcoholic drinks in the past week.

Secondary outcome measures

No secondary outcome measures.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Participants are members of an online access panel
2. In the ages between 15 and 20 years, either sex
3. Participants have to fulfill criteria regarding binge drinking. For 15 to 16 year-olds this means that they have to engage in binge drinking at least once a month. For 17 to 20 year-olds, it means engaging in binge drinking at least once a week.

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Online panel members who are younger than 15 or older than 20 years old
2. Online panel members who do not meet our criteria for binge drinking

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Montessorilaan 3
6500 HE

Sponsor information


The Netherlands Organisation for Health Research and Development (ZonMw) (Netherlands)

Sponsor details

Postbox 93 245
The Hague
2509 AE

Sponsor type

Research organisation



Funder type

Research organisation

Funder name

The Netherlands Organisation for Health Research and Development (ZonMw) (Netherlands)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes