An interventional study of Common Elements Toolbox and Active Control in Depressive Symptoms, Anxiety and Happiness, sponsored by University of Pennsylvania. Withdrawn at 2 sites in 2 countries. Open to participants aged 13 Years to 20 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-06-11.
Sponsored by University of Pennsylvania · Not applicable, Interventional, and Prevention
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).
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Inclusion Criteria:
Behavioral: Common Elements Toolbox
Behavioral: Active Control
COMET is an online unguided self-help intervention that lasts approximately 40-50 minutes.
Also known as: COMET
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.
Change in Patient Health Questionnaire-8 (PHQ-8)
Depression questionnaire. Scores range from 0 to 24. Lower scores indicate less depression.
Time frame: 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.
Time frame: 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.
Time frame: Up to 4 weeks post-intervention
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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: 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.
Time frame: Up to 4 weeks post-intervention
Plan to share: No
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This study is withdrawn, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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