SOVA Ambassadors Community Setting

Average number of articles written per participant; Research team extract data from websites and observation notes

Average number of submissions to questions on the REDCap form per participant in the Attention control arm Research team extract data from REDCap

Acceptability of Intervention Measure; Open-ended question

Open-ended question

Single item open-ended question

Patient Health Questionnaire-9 (Kroenke, 2001) measures depression severity with a score ranging from 0 to 27, a higher score indicating greater severity.

Patient Health Questionnaire-9 (Kroenke, 2001) measures depression severity with a score ranging from 0 to 27, a higher score indicating greater severity.

Generalized Anxiety Disorders 7-item Questionnaire (Spitzer, 2007) measures extent of anxiety symptoms. The total score ranges from 0 to 21 with a higher score indicating greater severity.

Generalized Anxiety Disorders 7-item Questionnaire (Spitzer, 2007) measures extent of anxiety symptoms. The total score ranges from 0 to 21 with a higher score indicating greater severity.

Positive Youth Development will be assessed using The Positive Youth Development Very Short Form (PYD-VSF) (Geldhof et al., 2014). The PYD-VSF is a questionnaire that measures adolescent strengths based on the Lerner and Lerner Five Cs of PYD (Lerner et al., 2005): competence (3 items, total score ranging from 3 to 12) (α = 0.12), connection (4 items, total score ranging from 4 to 20) (α = 0.78), confidence (3 items, total score ranging from 3 to 13) (α = 0.78), caring (3 items, total score ranging from 3 to 15) (α = 0.85), and character (4 items, total score ranging from 4 to 19) (α = 0.45). The PYD-SF was shown to have structural validity evidence that ran parallel with its derivative, the PYD-Short Form, among a population of adolescents (Geldhof et al., 2014).

Positive Youth Development will be assessed using The Positive Youth Development Very Short Form (PYD-VSF) (Geldhof et al., 2014). The PYD-VSF is a questionnaire that measures adolescent strengths based on the Lerner and Lerner Five Cs of PYD (Lerner et al., 2005): competence (3 items, total score ranging from 3 to 12) (α = 0.12), connection (4 items, total score ranging from 4 to 20) (α = 0.78), confidence (3 items, total score ranging from 3 to 13) (α = 0.78), caring (3 items, total score ranging from 3 to 15) (α = 0.85), and character (4 items, total score ranging from 4 to 19) (α = 0.45). The PYD-SF was shown to have structural validity evidence that ran parallel with its derivative, the PYD-Short Form, among a population of adolescents (Geldhof et al., 2014).

The 10-item Rosenberg Self-Esteem Scale (RSES) (Rosenberg, 1965) (α = 0.93) will be administered to assess participants' self-esteem. Items on the Rosenberg Self-Esteem Scale ask about self-worth and self-acceptance and are scored using a four-point scale from 1 = strongly disagree, to 4 = strongly agree. The scores on each question are summed together, with higher scores indicating greater self-esteem. The RSES is the most widely used measure of global self-esteem in the literature (Blascovich & Tomaka, 1991) and demonstrates concurrent, predictive and construct validity with being significantly correlated with other measures of self-esteem and predictive measures of depression and anxiety (Morris Rosenberg, 1979).

The 10-item Rosenberg Self-Esteem Scale (RSES) (Rosenberg, 1965) (α = 0.93) will be administered to assess participants' self-esteem. Items on the Rosenberg Self-Esteem Scale ask about self-worth and self-acceptance and are scored using a four-point scale from 1 = strongly disagree, to 4 = strongly agree. The scores on each question are summed together, with higher scores indicating greater self-esteem. The RSES is the most widely used measure of global self-esteem in the literature (Blascovich & Tomaka, 1991) and demonstrates concurrent, predictive and construct validity with being significantly correlated with other measures of self-esteem and predictive measures of depression and anxiety (Morris Rosenberg, 1979).

Emotional self-efficacy will be assessed using The Mental Health Self-Efficacy Scale (MHSES) (α = 0.82). MHSES was developed according to guidelines by Bandura as to how to create self-efficacy questionnaires (Bandura, 2006) . The questionnaire contains five items asking about the participant's confidence level in performing mental health self-care behaviors. Scoring of the MHSES is based on a five-point Likert scale (0 = disagree very much, to 5 = agree very much).

Emotional self-efficacy will be assessed using The Mental Health Self-Efficacy Scale (MHSES) (α = 0.82). MHSES was developed according to guidelines by Bandura as to how to create self-efficacy questionnaires (Bandura, 2006) . The questionnaire contains five items asking about the participant's confidence level in performing mental health self-care behaviors. Scoring of the MHSES is based on a five-point Likert scale (0 = disagree very much, to 5 = agree very much).

The Medical Outcome Study Social Support Scale (Sherbourne, 1991) measures types of social support. This subscale ranges from 0-100, with higher levels associated with greater support. We will use the emotional/informational subscale from this report. (Measured in adolescent and parents)

The Medical Outcome Study Social Support Scale (Sherbourne, 1991) measures types of social support. This subscale ranges from 0-100, with higher levels associated with greater support. We will use the emotional/informational subscale from this report. (Measured in adolescent and parents)

The revised UCLA Loneliness Scale will be administered to all participants to measure social isolation (α = 0.93). This 20-item scale measures one's feelings of social isolation and is scored using a four-point scale (1 = never; 2 = rarely; 3 = sometimes; 4 = often) (Russell, Peplau, & Cutrona, 1980). The revised measure was updated to counter possible effects of response bias and was shown to have evidence for concurrent and discriminant validity among college students (Russell et al., 1980).

The revised UCLA Loneliness Scale will be administered to all participants to measure social isolation (α = 0.93). This 20-item scale measures one's feelings of social isolation and is scored using a four-point scale (1 = never; 2 = rarely; 3 = sometimes; 4 = often) (Russell, Peplau, & Cutrona, 1980). The revised measure was updated to counter possible effects of response bias and was shown to have evidence for concurrent and discriminant validity among college students (Russell et al., 1980).

The Depression Stigma Scale (Griffiths 2004) measures stigmatizing attitudes toward depression treatment. It is a continuous measure and the total score ranges from 0-36. There are two subscales: the personal stigma subscale which totals 0-18 and the perceived stigma subscale which totals 0-18. These two are summed for the total stigma score. A higher score indicates a worse outcome.

The Depression Stigma Scale (Griffiths 2004) measures stigmatizing attitudes toward depression treatment. It is a continuous measure and the total score ranges from 0-36. There are two subscales: the personal stigma subscale which totals 0-18 and the perceived stigma subscale which totals 0-18. These two are summed for the total stigma score. A higher score indicates a worse outcome.