Table 1 Eligibility criteria

Inclusion criteria

1) Aged between 12 and 26 years old.

2) Adversity:

a. Childhood trauma:

Prior exposure to at least one form of childhood trauma defined as moderate or severe physical (score ≥ 10), sexual (score ≥ 8) and/or emotional (score ≥ 13) abuse, emotional (score ≥ 15), and/or physical (score ≥ 10) neglect, according to established severity categories of the Childhood Trauma Questionnaire (CTQ) [63,64,65], and/or

b. Peer bullying:

Exposure to moderate or severe peer bullying, measured with the Retrospective Bully Questionnaire (RBQ) (score of frequency of bullying in one or more ways “sometimes” or more often and/or classified the experience as “quite serious” or “extremely serious”) [66], and/or

c. Parental conflict:

A score of moderate or severe parental conflict, measured with the Childhood Experiences of Care and Abuse Questionnaire (CECA.Q) section Parental Conflict (frequency score of “regularly” or “often” and/or a severity score of “serious” or “violence”) [67].

3) Self-esteem below average (measured with the Rosenberg Self-Esteem Scale (RSES) (score < 26) [51, 68].

4) Willingness to participate in the SELFIE intervention.

5) Ability to give written informed consent.

6) Parental consent for minors.

Exclusion criteria

1) Insufficient command of Dutch

2) Psychiatric symptoms due to an organic cause