Evaluating an Online Wellness Intervention for Greek Adolescents

Evaluating an Online Single-session Intervention for Mental Health and Wellness of Greek Adolescents

The investigators are evaluating the effects of an online single-session mental health intervention (the Common Elements Toolbox; COMET). To evaluate COMET, the investigators are conducting a randomized controlled trial with Greek adolescents attending high school in the Attica region in Greece. Students will be randomized to the COMET condition or to an active control condition.

Primary outcome measures (depressive symptoms, anxiety symptoms, subjective well-being) will be measured at two weeks post-intervention and four weeks post-intervention.

The investigators will evaluate COMET as a universal intervention (using the full sample) and as a targeted intervention (analyzing those who reported elevated depressive symptoms or anxiety symptoms at baseline).

Study Overview

• Status: Withdrawn
• Conditions: Anxiety; Depressive Symptoms; Happiness
• Intervention / Treatment: Behavioral: Common Elements Toolbox; Behavioral: Active Control

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Greece
  • Athens, Greece, 15121
    • Eginition Hospital National and Kapodistrian University of Athens School of Medicine
• United States
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • UNIVERSITY of PENNSYLVANIA

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 13 years to 20 years (Child, Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Between 13 and 20 years old and a student at a participating Greek high school. Access to the internet.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active Control Condition	Behavioral: Active Control; The active control condition includes an online self-awareness program that lasts approximately 40-50 minutes. Participants in the control condition will receive access to the intervention after data collection for the study has been completed.
Experimental: Common Elements Toolbox (COMET)	Behavioral: Common Elements Toolbox; COMET is an online unguided self-help intervention that lasts approximately 40-50 minutes.; Other Names: COMET

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Patient Health Questionnaire-8 (PHQ-8)	Depression questionnaire. Scores range from 0 to 24. Lower scores indicate less depression.	Up to 4 weeks post-intervention
Change in Generalized Anxiety Disorder Screener-7 (GAD-7)	Anxiety questionnaire. Total scores range from 0-21. Lower scores indicate less anxiety.	Up to 4 weeks post-intervention
Change in the Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS)	Subjective Well-being questionnaire. Total scores range from 7 to 35. Higher values indicate higher well-being scores.	Up to 4 weeks post-intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ratings on the Acceptability of Intervention Measure (AIM)	Questionnaire measuring the acceptability of an intervention. Acceptability refers to the perception that a given treatment is agreeable or satisfactory. The total score ranges from 4 to 20. Higher scores indicate higher acceptability ratings.	Immediately after the intervention
Ratings on the Intervention Appropriateness Measure (IAM)	Questionnaire measuring the appropriateness of an intervention. Appropriateness refers to the perceived fit or relevance of an intervention. The total score ranges from 4 to 20. Higher scores indicate higher appropriateness.	Immediately after the intervention
Secondary Control	The investigators will ask participants three items to assess secondary control (Weisz et al., 2010). The items are scored on a 4-point Likert scale, ranging from 0 ("Very false") to 3 ("Very true"). The three items are: When something bad happens, I can find a way to think about it that makes me feel better. After a really hard day, I can make myself feel better by remembering some good things that happened. When bad things happen to me that I can't control, there are lots of things I can do to feel better. Higher scores indicate greater secondary control.	Up to 4 weeks post-intervention
Perceived Utility	Participants will be asked to rate three items relating to the perceived utility of each module. Specifically, the investigators asked participants: How helpful the module was; How engaging the module was; How much they will continue applying content from the module. If items are at least moderately correlated (r > .5) the investigators will combine them in a single measure of perceived utility. Higher scores indicate greater perceived utility.	Immediately after intervention
Positive and Negative Affect Schedule (PANAS)	Questionnaire measuring positive affect and negative affect. Scores on the positive affect subscale range from 10-50, with higher scores representing higher levels of positive affect. Scores on the negative affect subscale range from 10-50, with lower scores representing lower levels of negative affect.	Up to 4 weeks post-intervention

Collaborators and Investigators

• Sponsor: University of Pennsylvania
• Collaborators: National and Kapodistrian University of Athens, Greece; University Mental Health, Neurosciences and Precision Medicine Research Institute "Costas Stefanis," Greece

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2021
• Primary Completion (Estimated): June 1, 2022
• Study Completion (Estimated): December 1, 2022

Study Registration Dates

• First Submitted: March 22, 2021
• First Submitted That Met QC Criteria: March 22, 2021
• First Posted (Actual): March 25, 2021

Study Record Updates

• Last Update Posted (Actual): June 11, 2025
• Last Update Submitted That Met QC Criteria: June 6, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Behavioral Symptoms; Depression
• Other Study ID Numbers: 844481

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No