Study questionnaires
| Construct | Measure and description | Informant |
| Child/youth mental health | Ontario Child Health Study Emotional Behavioural Scales55 56 52-item symptom checklist providing total, internalising and externalising scores, as well as subscale scores for major depressive disorder, separation anxiety, social phobia, generalised anxiety, attention-deficit hyperactivity, oppositional defiant disorder and conduct disorder | Child/youth and parent |
| Strengths and Difficulties Questionnaire87 25-item checklist providing total difficulties scores, as well as domains of emotional problems, conduct problems, hyperactivity, peer problems and prosocial | Parent | |
| Child/youth psychosocial health | KIDSCREEN88 27-item scale of health-related quality of life with domain scores for physical well-being, psychological well-being, autonomy and parent relations, peers and social support and school environment | Child/youth and parent |
| Self Description Questionnaire89 90 Five items from the General Self-image subscale; adapted from the National Longitudinal Survey of Children and Youth | Child/youth and parent | |
| Self-Perception Profile for Children91 92 36-item scale assessing self-concept in the domains of scholastic competence, social acceptance, athletic competence, physical appearance, behavioural conduct and global self-worth | Child/youth | |
| Child/youth physical health | WHO Disability Assessment Schedule 2.093 94 12-item measure of disability and functioning in the domains of cognition, mobility, self-care, getting along, life activities and participation | Child/youth and parent |
| Child/youth intelligence | Kaufman Brief Intelligence Test, second edition95 Brief measure of verbal and non-verbal intelligence | Child/youth |
| Parent mental health | Center for Epidemiologic Studies Depression Scale96 20-item measure of depressive symptoms across four domains depressed affect, positive affect, somatic activity and interpersonal relations | Parent |
| Generalized Anxiety Disorder97 Seven items measuring symptoms of generalised anxiety | Parent | |
| Parent quality of life | Short Form-3698 36-item scale that assesses eight health domains: physical functioning, bodily pain, role limitations due to physical health problems, role limitations due to personal or emotional problems, emotional well-being, social functioning, energy/fatigue and general health perceptions, and a single item that provides an indication of perceived change in health | Parent |
| Family environment | McMaster Family Assessment Device99 100 12 items comprising the General Functioning subscale measures aspects of communication, problem solving, behavioural control, affective responsiveness and involvement and roles | Parent |
| Parental Stress Scale101 102 18-item scale that includes four domains of parenting: rewards, stressors, loss of control and satisfaction | Parent | |
| Sibling Inventory of Differential Experience103 18-item scale assessing differential treatment by mother and father in relation to closest-aged sibling | Child/youth | |
| School environment and peers | 2014 Ontario Child Health Study (OCHS)104 14 items assessing school climate, bullying and participation in extra-curricular activities | Child/youth |
| Mental healthcare | Various items obtained from the OCHS and Canadian Community Health Survey | Parent |
| Sociodemographics | Various items obtained from population-based surveys conducted by Statistics Canada | Parent |
Only youth ≥10 provided self-reported data.