NAVO:J School-Based Group Intervention for Adolescent Mental Health

Depression is measured using the Korean version of the Patient Health Questionnaire-9 (PHQ-9), based on the DSM-IV criteria for major depressive disorder, assessing symptoms experienced over the past two weeks. The scale consists of 9 items rated on a 4-point Likert scale (score range: 0-27). Higher scores indicate more severe depressive symptoms. Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Resilience is measured using the 10-item Connor-Davidson Resilience Scale (CD-RISC-10), a self-report measure of an individual's ability to recover and adapt under adversity or stress. Each item is rated on a 5-point Likert scale (score range: 0-40). Higher scores indicate greater resilience. Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

The Maum-EASY Test is a self-report screening tool developed to detect students' mental health problems early and prevent worsening. The anxiety and depression subscale measures the level of anxiety- and depression-related problems, with each item rated on a 4-point Likert scale (0-3). Higher scores indicate a greater likelihood of such problems (score range: 0-24). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

The suicide and crisis subscale of the Maum-EASY Test measures the level of serious risk symptoms such as suicidality and severe psychological problems, with each item rated on a 4-point Likert scale (0-3). Higher scores indicate a greater need for priority attention and intervention (score range: 0-18). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

The externalizing subscale of the Maum-EASY Test measures the level of outwardly expressed behavioral problems, with each item rated on a 4-point Likert scale (0-3). Higher scores indicate a greater likelihood of problems such as oppositional behavior, delinquency, and habitual lying (score range: 0-24). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

The psychological trauma subscale of the Maum-EASY Test measures the presence of traumatic experiences and related problems, with each item rated on a 4-point Likert scale (0-3). Higher scores indicate a greater likelihood of problems such as intrusive memories, avoidance of others, and distrust of others (score range: 0-21). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

The school life adjustment subscale of the Maum-EASY Test measures difficulties related to school adjustment and reduced coping skills, with each item rated on a 4-point Likert scale (0-3). Higher scores indicate a greater likelihood of problems such as lack of confidence, maladaptive coping, and difficulty making friends (score range: 0-21). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Subjective mental health is measured using a self-report Visual Analog Scale (VAS) developed by the research team to multidimensionally assess adolescents' perceived mental health. It consists of 9 items, each rated on an 11-point scale from 0 (not at all) to 10 (very much). It is used as a supplementary measure of overall perceived mental health. Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Empathy is measured using the Korean version of the Empathy Quotient (K-EQ), which assesses multidimensional empathic ability across cognitive empathy, emotional empathy, and social skills. It consists of 17 items rated on a 4-point Likert scale (score range: 17-68). Higher scores indicate greater empathic ability. Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Grit is measured using the Short Grit Scale (GRIT-S), comprising two subfactors: consistency of effort and consistency of interest. It consists of 8 items rated on a 5-point Likert scale (score range: 6-30). Higher scores indicate greater grit. Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Personality is measured using a 15-item short form of the Big Five Inventory, comprising five subfactors: neuroticism, extraversion, openness, agreeableness, and conscientiousness. Each item is rated on a 5-point Likert scale from 1 (strongly disagree) to 5 (strongly agree) (score range: 15-75). Change is assessed by comparing scores at baseline, mid-point, and post-intervention.

Objective adherence is assessed using NAVO:J platform log data, including app access time and the scope of activities completed during the study period. This measure is used to verify participant compliance with the intervention.

Subjective adherence is assessed using a self-report questionnaire on the number and duration of app sessions during the study period, administered at the post-intervention assessment.

App satisfaction is assessed using a self-report questionnaire evaluating ease of use, information reliability and quality, perceived improvement in mental health, and overall satisfaction, administered at the post-intervention assessment.