Description of measures and timepoints
| Measure | Domain | Scoring description | Method of assessment | Baseline | Intervention | 6- month | 18- month |
| Primary outcome | |||||||
| Corsi Block Forward Tapping Task41 | Visuo-spatial short-term memory/immediate attention | Raw scores for longest recall span will be used to determine visual short-term memory/immediate attention | Child assessment | · | · | ||
| Secondary outcomes | |||||||
| Child | |||||||
| Digit Span Forward41 | Verbal immediate attention/short-term memory | Raw scores for longest recall span will be used to determine verbal immediate attention | Child assessment | · | · | ||
| Corsi Block Backward Tapping Task41 | Visuo-spatial working memory | Use of raw scores, indicating longest backward recall span | Child assessment | · | · | ||
| Digit Span Backwards41 | Verbal working memory | Use of raw scores, indicating longest backward recall span | Child assessment | · | · | ||
| NIH Toolbox, Flanker Inhibitory Control and Attention Test46 | Inhibitory control, attention | Raw scores range from 0 to 10, with standard scores mean=100 (SD=15) used in reporting | Child assessment | · | · | ||
| NIH Toolbox, Dimensional Change Card Sort | Cognitive flexibility | Raw scores | Child assessment | · | |||
| Sustained Attention to Response Task | Sustained attention | Standard scores mean=100 (SD=15) | Child assessment | · | |||
| Strengths and Difficulties Questionnaire47 | Child mental-health related behaviour | A 25-item validated measure for children aged 4–16 years; with higher scores representing higher levels of behaviour/mental health difficulties. Measure reports subscales for internalising difficulties (5 items), externalising difficulties (10 items) and total difficulties (20 items) | Parent and teacher survey | · | · | · | |
| Affective Reactivity Index | Emotion-regulation | A 7-item measure, with a range of 0–14, with higher scores representing greater irritability | Parent survey | · | · | · | |
| Childhood Executive Functioning Inventory48 | Executive functioning behaviour | A 24-item measure validated for children aged 4–12 years. Each item is scored 1–5, with higher scores representing greater difficulties. It yields two subscales: inhibition (11-items) and working memory (13-items) | Parent and teacher survey | · | · | · | |
| ECLS-K Approaches to Learning49 | Learning behaviour | A 6-item subscale from the Social Rating Scale used in Early Childhood Longitudinal Study-Kindergarten (ECLS-K). Items were designed to assess various aspects of a child’s approach to learning, such as organisation, working independently and task completion. The possible score range was 1–6, with higher scores indicating better approaches to learning | Teacher survey | · | · | · | |
| Parent | |||||||
| Interpersonal Mindfulness in Parenting50 | Mindful parenting, parent–child interaction (four subscales) | 10-item measure, with subscales for awareness and present-centred attention (4-items), non-judgement (3-items) and non-reactivity (3-items) | Parent survey | · | · | · | |
| Short Warwick Edinburgh Mental Well-Being Scale (SWEMWBS)51 | Mental well-being | 7-item scale which yields a single score ranging from 7 to 35, with higher scores representing better well-being | Parent survey | · | · | · | |
| Kessler-6 (K-6)52 | Psychological distress | A 6-item, self-reported and validated measure of mental health distress, with higher scores indicating greater psychological distress | Parent survey | · | · | ||
| Teacher | |||||||
| Mindfulness in Teaching Scale | Teacher mindfulness | 14-item self-report measure, with Teacher Intrapersonal Mindfulness (9-items, range 9–45) and Teacher Interpersonal Mindfulness subscales (7 items, range 7–35), with higher scores representing more negative outcomes | Teacher survey | · | · | · | |
| Student-Teacher Relationship Scale-Short Form53 | Quality of student–teacher relationships | 14-item measure, with possible score range was 28–75, with higher scores representing a more positive relationship between the teacher and the child | Teacher survey | · | · | · | |
| SWEMWBS51 | Mental well-being | 7-item scale which yields a single score ranging from 7 to 35, with higher scores representing better well-being | Teacher survey | · | · | · | |
| K-652 | Psychological distress | A 6-item, self-reported and validated measure of mental health distress, with higher scores indicating greater psychological distress | Teacher survey | · | · | · | |
| CLASS | Classroom environment/quality, teacher–student interactions | Widely used observational tool (1 hour) that assesses dimensions of classroom interactions linked to student achievement and classroom quality (emotional support, classroom organisation and instructional support) | Research assistant | · | |||
| Confounders | |||||||
| Woodcock Johnson—3rd edition54 | General cognitive/intellectual and non-verbal ability | Standard scores will be used, with mean 100, SD=15 | Child | · | |||
| Family demographics | Parent survey | · | |||||
| Teacher demographics | Teacher survey | · | |||||
CLASS, Classroom Assessment Scoring System; NIH, National Institute of Health; WJIII, Woodcock–Johnson Tests of Cognitive Abilities - 3.