SIYA-PT: An Internet-based CBT Intervention to Enhance Low Self-esteem Among Portuguese Emerging Adults

IG will have access to the intervention (SIYA-PT). The participants will have an individual login to use the platform, and have access to the modules and the measures that need to be filled out throughout the study.

SIYA-PT has seven modules:

Module 1 - Introduction Module 2 - Achievements and self-esteem Module 3 - Relationships and self-esteem Module 4 - Independence and self-esteem Module 5 - Dealing with adversities Module 6 - Self-acceptance Module 7 - Termination and continuation

WCG will not receive the intervention while IG goes through SIYA-PT. The participants will have an individual login to access the platform to answer the self-reported measures weekly to monitor their well-being. The participants will also have access to messaging to be able to contact the clinical psychologist on the platform if there is increase in their, e.g., anxiety and depressive symptoms. After the end of IG intervention and the follow-up , three months, WCG will receive the same SIYA-PT intervention.

SIYA-PT has seven modules:

Module 1 - Introduction Module 2 - Achievements and self-esteem Module 3 - Relationships and self-esteem Module 4 - Independence and self-esteem Module 5 - Dealing with adversities Module 6 - Self-acceptance Module 7 - Termination and continuation

A 10-item self-report measure to assess global self-esteem. The RSE (Rosenberg, 1965; Pechorro et al., 2011) uses a 4-point Likert scale to rate agreement with the statements, from 0 (Strongly disagree) to 3 (Strongly agree). Scores vary from 0 to 30, with higher scores indicating higher levels of global self-esteem.

A 30-item self-report measure to assess global self-esteem. The RSCQ (Robson, 1989) uses a 7-point Likert scale to rate agreement with each statement, from 0 (Completely disagree) to 7 (Completely agree). Scores vary from 0 to 210, with higher scores indicating higher levels of global self-esteem.

A seven-item self-report measure to assess generalised anxiety disorder according to DSM-IV criteria. GAD-7 (Spitzer et al., 2006; Sousa et al., 2015) uses a 4-point Likert scale to rate how often one has experienced the described situation, from 0 (Never) to 3 (Almost every day). Scores vary from 0 to 21, with higher scores indicating higher levels of anxiety.

A nine-item self-report measure to assess depressive symptoms according to DSM-IV criteria. PHQ-9 (Kroenke et al., 2001; Lamela et al., 2020) uses a 4-point Likert scale to rate how often one has experienced the described situation, from 0 (Never) to 3 (Almost every day). Scores vary from 0 to 27, with higher scores indicating higher levels of depressive symptoms.

A 26-item self-report measure with four domains (physical health, psychological health, social relationships and environment) to assess perceived quality of life. WHOQOL-BREF (The WHOQOL Group, 1998; Vaz Serra et al., 2006) uses a 5-point Likert scale, from 1 ("Very Poor", "Not at all" or "Very dissatisfied") to 5 ("Very good", "Completely", "Always" or "Very satisfied") to ask how one feels about their quality of life, health, or other areas of their life. Scores vary from 0 to 100, with higher scores indicating higher perceived quality of life.

A 26-item self-report measure with six subscales (Self-Kindness, self-judgment, common humanity, isolation, mindfulness, and over-identification) that assesses how one typically responds in difficult times in terms of self-compassion. SCS (Neff, 2003; Castilho & Pinto-Gouveia, 2015) uses a 5-point Likert scale to rate how often one does each behaviour described in each item, from 1 (Almost never) to 5 (Almost always). Higher scores indicate higher levels of self-compassion.

A 30-item self-report measure to assess assertive behaviour. RAS (Rathus, 1973; Detry & Castro, 1990) uses a 6-point Likert scale to rate how well each item describes the person, from 5 (Very much like me) to 0 (Very much unlike me). Scores vary from 0 to 30, with higher scores indicating higher assertiveness.

A 10-item self-report measure to screen for three areas (alcohol consumption, dependence symptoms and alcohol-related problems) of alcohol-use-related problems using a 5-point Likert scale. AUDIT (WHO, 1989) scores vary from 0 to 40, from 0 to 4, with higher scores indicating higher levels of alcohol-use-related problems.

An interview guide with 14 questions developed by the research team based on questions from Mini International Neuropsychiatric Interview (Sheehan et al., 1998)'s subscale for Suicide Ideation and DSM-5-TR criteria for Major Depressive Disorder with a dichotomous answer - No or Yes.