Positive Events Training to Enhance Positive Emotions in Adolescents With Elevated Depressive Symptoms: An N=1 Trial

NCT07825285 | Enrolling By Invitation DMC

• 2 other identifiers: G-2026-11398-R2(MIN)G051625N
• Study Type: interventional
• Target: 1
• Locations: 1 country
• Sites: 1

Brief Summary

Research shows that high positive emotionality is an essential ingredient in building resilience in youngsters, especially those with a vulnerability to develop depressive symptomatology. It may empower youngsters against actual depression and its various long-term adverse outcomes. One way to achieve positive emotions is via the recollection and anticipation of specific positive events. Therefore, to cultivate positive emotions in young people, the researchers developed a user-friendly training program translated from basic research findings: Positive Event Training (PET). Through PET, adolescents learn to solidify positive memories and positive plans. This low-threshold program, delivered as a group training at secondary schools, was well received by adolescents in a previous project of our lab (Recalling and Anticipating Specific Positive Events to boost Resilience in Adolescents). In the context of the current study, the PET program, which normally consists of four 1-hour sessions, will be delivered in three individual sessions. The previous project at secondary schools showed that PET leads to heightened positive emotions particularly among youths with elevated depressive tendencies. This indicates that PET can offer increased resilience against depression, especially for vulnerable young individuals. In our current project, the researchers conduct a comprehensive, fine-grained evaluation of the PET program's effectiveness, delivered in an individual format, by collecting intensive data and detailed participant feedback.

Conditions

Emotional Distress; Anhedonia

Keywords

positive emotions; anhedonia; positive affect regulation; emotional distress; autobiographical thinking

Outcome Measures

Primary Outcomes (10)

• Daily-life positive emotions measured via daily diary items at baseline (adapted from Kirtley et al., 2022)

  Mean value of four daily diary items (i.e., "How relaxed, content, enthusiast, good do you feel?"), rated on a 0 ("not at all") to 100 ("a lot") rating scale. Higher values represent, higher levels of positive emotions (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) before the start of the training: Day 1a + all consecutive days until Day 30a (= day before the start of the training)

• Daily-life positive emotions measured via daily diary items at post-training (adapted from Kirtley et al., 2022)

  Mean value of four daily diary items (i.e., "How relaxed, content, enthusiast, good do you feel?"), rated on a 0 ("not at all") to 100 ("a lot") rating scale. Higher values represent, higher levels of positive emotions (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) immediately after the end of the training: Day 1b = the day after the final training day + all consecutive days until Day 30b

• Daily-life anhedonia measured via daily diary items at baseline (adapted from Bogaert et al., 2023)

  Mean value of three daily diary items tapping into difficulties experiencing consummatory pleasure, anticipatory pleasure and motivational difficulties using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you find it difficult to enjoy yourself?"; "To what extent did you look forward to doing enjoyable things? (reverse-scored), "Conditional: if 0-50 ("not at all - neutral"): Was this because there really weren't any enjoyable things to look forward to, or because they were there but you couldn't really look forward to them?; "How happy did you feel?" (reverse-scored)). Higher score reflects higher levels of anhedonia (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) before the start of the training: Day 1a + all consecutive days until Day 30a (= day before the start of the training)

• Daily-life anhedonia measured via daily diary items at post-training (adapted from Bogaert et al., 2023)

  Mean value of three daily diary items tapping into difficulties experiencing consummatory pleasure, anticipatory pleasure and motivational difficulties using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you find it difficult to enjoy yourself?"; "To what extent did you look forward to doing enjoyable things? (reverse-scored), "Conditional: if 0-50 ("not at all - neutral"): Was this because there really weren't any enjoyable things to look forward to, or because they were there but you couldn't really look forward to them?; "How happy did you feel?" (reverse-scored)). Higher score reflects higher levels of anhedonia (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) immediately after the end of the training: Day 1b = the day after the final training day + all consecutive days until Day 30b

• Daily-life dampening measured via daily diary items at baseline (adapted from Gérardy et al., in preparation; simplified to better fit target group of adolescents)

  Mean value of four daily life items to measure mental strategies to reduce the intensity and/or frequency of positive emotions, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you think, "This pleasant feeling won't last"?"; "To what extent did you think, "I don't deserve to feel good"?"; To what extent did you think, "Something might go wrong that will make my good/pleasant feeling go away"?; "To what extent did you think about how difficult it would be if your good/pleasant feeling suddenly disappeared?"). Higher score reflects higher levels of dampening (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) before the start of the training: Day 1a + all consecutive days until Day 30a (= day before the start of the training)

• Daily-life dampening measured via daily diary items at post-training (adapted from Gérardy et al., in preparation; simplified to better fit target group of adolescents)

  Mean value of four daily life items to measure mental strategies to reduce the intensity and/or frequency of positive emotions, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you think, "This pleasant feeling won't last"?"; "To what extent did you think, "I don't deserve to feel good"?"; To what extent did you think, "Something might go wrong that will make my good/pleasant feeling go away"?; "To what extent did you think about how difficult it would be if your good/pleasant feeling suddenly disappeared?"). Higher score reflects higher levels of dampening (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) immediately after the end of the training: Day 1b = the day after the final training day + all consecutive days until Day 30b

• Daily-life savoring measured via daily diary items at baseline (adapted from Gérardy et al., in preparation; simplified to better fit target group of adolescents)

  Mean value of two daily life items tapping into the the engagement in attending to, appreciating and enhancing positive experiences, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you allow the good/pleasant feeling to be there and simply let it be?", "To what extent did you try to really focus your attention on the good/pleasant feeling in order to fully experience it and truly enjoy it?"). Higher scores reflect a higher tendency to savor (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) before the start of the training: Day 1a + all consecutive days until Day 30a (= day before the start of the training)

• Daily-life savoring measured via daily diary items at post-training (adapted from Gérardy et al., in preparation; simplified to better fit target group of adolescents)

  Mean value of two daily life items tapping into the the engagement in attending to, appreciating and enhancing positive experiences, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "To what extent did you allow the good/pleasant feeling to be there and simply let it be?", "To what extent did you try to really focus your attention on the good/pleasant feeling in order to fully experience it and truly enjoy it?"). Higher scores reflect a higher tendency to savor (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) immediately after the end of the training: Day 1b = the day after the final training day + all consecutive days until Day 30b

• Daily-life emotional distress measured via daily diary items at baseline (derived from Bogaert et al., 2023)

  Mean value of three daily diary items to measure anxiety, stress and depressed feelings, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "How anxious did you feel?"; "How depressed (down) did you feel?"; "How stressed did you feel?"). A higher score reflects higher levels of emotional distress (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) before the start of the training: Day 1a + all consecutive days until Day 30a (= day before the start of the training)

• Daily-life emotional distress measured via daily diary items at post-training (derived from Bogaert et al., 2023)

  Mean value of three daily diary items to measure anxiety, stress and depressed feelings, using a 0-100 Likert scale (0 = "not at all", 100 = "a lot"; items: "How anxious did you feel?"; "How depressed (down) did you feel?"; "How stressed did you feel?"). A higher score reflects higher levels of emotional distress (min = 0, max = 100).

  One month (30 days) of daily diaries (3x/day) immediately after the end of the training: Day 1b = the day after the final training day + all consecutive days until Day 30b

Secondary Outcomes (28)

• Episodic future thinking features measured via the Episodic Future Thinking Test (EFT-T; Hallford et al., 2019), and single item rating scales per generated event at baseline

  Single timepoint, participants are invited to complete the survey before the start of the training (= the day before Day 1a, which is the start of the daily diary assessment phase)

• Autobiographical memory features measured via the Autobiographical Memory (AM) Test (AMT; Raes, Williams, & Hermans, 2009) and single item rating scales per generated event at baseline

  Single timepoint, participants are invited to complete the survey before the start of the training (= the day before Day 1a, which is the start of the daily diary assessment phase)

• Positive Affect subscale of the Positive and Negative Affect Schedule Scales (PANAS; Watson et al., 1988) at baseline

  Single timepoint, participants are invited to complete the survey before the start of the training (= the day before Day 1a, which is the start of the daily diary assessment phase)

• Leuven Anhedonia Scale (LASS, 2nd version; Nelis et al., 2018) at baseline

  Single timepoint, participants are invited to complete the survey before the start of the training (= the day before Day 1a, which is the start of the daily diary assessment phase)

• Dampening measured via the Leuven Exeter Dampening Scale (LEDS, Bogaert et al., 2025) at baseline

  Single timepoint, participants are invited to complete the survey before the start of the training (= the day before Day 1a, which is the start of the daily diary assessment phase)

Other Outcomes (1)

• Open questions measuring the engagement with the training material, implementation in daily life and general experiences related to the training

  Single timepoint, participants are invited to complete the survey immediately after the end of the training (= the day after the final training session or Day 1b)

Study Arms (1)

Positive Events Training (PET)

EXPERIMENTAL

Behavioral: Positive Events Training (PET)

Behavioral: Positive Events Training (PET)

Interventions

Positive Events Training (PET) BEHAVIORAL

Behavioral: Positive Events Training (PET) Positive Event Training or PET is a group-based training program combining Memory Specificity Training (MEST; Raes, 2007) and Future Event Specificity Training (FEST; Dutch version of Hallford et al. (2020): Changing the Future: An initial test of Future Specificity Training). Other Name:

Positive Events Training (PET)

Eligibility Criteria

• Age: 12 Years - 16 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17)

You may qualify if:

• moderate level of baseline depressive symptoms
• must be Dutch-speaking

You may not qualify if:

• \- /

Sponsors & Collaborators

• KU Leuven: lead

Study Sites (1)

Praktijkcentrum PraxisP

Leuven, 3000, Belgium

Location

MeSH Terms

Conditions

Anhedonia

Condition Hierarchy (Ancestors)

Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Filip Raes

  KU Leuven

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor Dr Filip Raes

Model Details: single-case experimental design

Study Record Dates

• First Submitted: September 2, 2026
• First Posted: September 17, 2026
• Study Start: October 1, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): December 1, 2028
• Last Updated: September 17, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1)