CONSORT-EHEALTH Checklist V1.6.2 Report

1b-i) Key features/functionalities/components of the intervention and comparator in the METHODS section of the ABSTRACT "A web-based randomized controlled trial tested two strategies (i.e., prototype alteration and cue reminders) within an existing online personalized feedback intervention (‘Drinktest’) aiming at reducing adults’ excessive drinking" "Excessive drinking adults (N=2634) were randomly assigned to four conditions" "one and six months follow-up" "Differences in drinking behavior, intentions and behavioral willingness (i.e., primary outcomes) were assessed by means of longitudinal multilevel analyses using a ‘last observation carried forward’ method." 1b-ii) Level of human involvement in the METHODS section of the ABSTRACT "Excessive drinking adults (N = 2634) were randomly assigned to four conditions: original Drinktest, Drinktest plus prototype alteration, Drinktest plus cue reminder, and Drinktest plus prototype alteration and cue reminder. " 1b-iii) Open vs. closed, web-based (self-assessment) vs. face-to-face assessments in the METHODS section of the ABSTRACT "Participants were recruited online and through printed materials." "Measures were based on self-reports." 1b-iv) RESULTS section in abstract must contain use data "N=2634) "All conditions showed reductions in drinking behavior and willingness to drink, and in increased intentions to reduce drinking" (regarding the primary outcomes) 1b-v) CONCLUSIONS/DISCUSSION in abstract for negative trials N/A, the study found changes in behavior, as expected. INTRODUCTION 2a-i) Problem and the type of system/solution "It is important to further our understanding of how to reduce excessive drinking" "A meta-analysis showed that, among the interventions that were based on the goal-striving Theory of Planned Behavior (TPB) components, only half were found to guide changes in intentions and two-third guided changes behavior, and only small effect sizes were produced." "The present study addresses these issues by examining the effect of two intervention strategies that could potentially help enhancing the effect of an existing online (i.e., web-based) tailored intervention, Drinktest.nl: prototype alteration and cue reminders." 2a-ii) Scientific background, rationale: What is known about the (type of) system "In the Netherlands, 12.9% of the general population engages in weekly binge drinking" "A majority of interventions have targeted drinking behavior assuming that behavior is intentional." "behaviors may occur without intentions or even when having intentions not to do so" "online self-help interventions have been found to be effective in reducing adults’ drinking behavior in the general population with an effect up to 6 or 9 months ... However, single-session interventions, such as Drinktest.nl, have been found to produce small effect sizes only" "In sum, the studies suggest that a significant proportion of intentions and behavior remains unexplained and that the effectiveness of interventions can be improved." "Experiments and intervention studies revealed that prototype alteration was effective in (1) postponing the onset of drinking among children aged 10– 12 years old with an effect up to two years, ..." "Although prototype alteration has been applied to alcohol use, only few interventions aimed at reducing excessive drinking based on dual-process models (PWM) have been applied to young adults (usually incorporating only university students), and results have been mixed ... there are no such interventions for the general adult population" "Cue reminders can support enactment of intentions as they can unconsciously prompt self-enhancing or self-protecting opportunities" METHODS 3a) CONSORT: Description of trial design (such as parallel, factorial) including allocation ratio "This study examined whether prototype alteration and provision of a cue reminder can be useful strategies to enhance the effectiveness of an existing online (i.e., web-based) tailored intervention, i.e., Drinktest.nl." "Expected was that (a) prototype alteration may intrinsically motivate people to drink less, (b) cue reminders may strengthen the salience of alcohol reduction goals, and (c) the combination of prototype alteration and a cue reminder may increase the salience and intrinsic motivation of alcohol reduction goals." 3b) CONSORT: Important changes to methods after trial commencement (such as eligibility criteria), with reasons There were no changes after trial commencement. 3b-i) Bug fixes, Downtimes, Content Changes The intervention has only been offline a couple of hours and should not have influenced the results. 4a) CONSORT: Eligibility criteria for participants "Eligible participants were individuals aged 18 or over engaging in excessive drinking: exceeding 14 and 21 or more glasses of alcohol per week or drinking 4 and 6 glasses or more per occasion for women and for men, respectively. This norm was set by the original Drinktest and was thus left unchanged."