Table 3.
Outcome measures
| Measure/definition | Source of measure | Data source | |
|---|---|---|---|
| Primary outcomes | |||
| Dropout/Completion | Drop-out is indicated if the student has a) not completed upper secondary school within five years after enrolment in upper secondary school, or b) if the student quit school and is without any regular activity during the course of the study period, i.e. grade 1-3 of upper secondary school. Completion of school year is indicated if the student has passed all subjects at the end of the current school year | Registry data | County registry data |
| Presence/Absence | Average days and average hours absent the past school year | Registry data | County registry data |
| Academic achievement | Average grade at closure of each school year in project period | Registry data | County registry data |
| Mental health | Short form of Symptom Check List (SCL-5) | Tambs et al., 1993 [34] | C1 and C2 Student survey |
| Mental wellbeing | Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS) | Clarke et al., 2011 [35] | C2 Student survey |
| Secondary outcomes | |||
| School satisfaction | Multidimensional Student’s Life Satisfaction Scale: Three items from the school satisfaction dimension | Huebner, 1994 [37] | C1 and C2 student survey |
| Loneliness | Loneliness Scale | Mittelmark et al., 2004 [39]; Kraft & Loeb, 1997 [38] | C1 and C2 student survey |
| Mediators | |||
| Relatedness | Wichstrøm Social Competence Scale | Wichstrøm, 1995 [41] | C1 and C2 student survey |
| Teacher and Classmate Support Scale | Torsheim et al., 2000 [44] | C1 and C2 student survey | |
| Positive Youth Development Connection Scale | Geldhof et al., 2014 [43]; Lerner et al., 2005 | C1 and C2 student survey | |
| How many close female friends do you currently have? | Single item | C1 and C2 student survey | |
| How many close male friends do you currently have? | Single item | C1 and C2 student survey | |
| Autonomy | Ten items from the Learning Climate Scale | Black & Deci, 2000 [45] | C1 and C2 student survey |
| Competence | How do you think you will perform academically this school year? | Single item | C1 and C2 student survey |
| Academic Self-Efficacy Scale | Roeser et al., 1996 [46] | C1 and C2 student survey | |
| Class climate | Caring Climate Scale (CCS) | Newton et al., 2007 [47] | C1 and C2 student survey |