Research with adults and older adolescents suggests a general factor may underlie both mental health difficulties and wellbeing. However, the classical bifactor model commonly used to demonstrate this general trait has recently been criticised when a unidimensional structure is not supported. Furthermore, research is lacking in this area with children and early adolescents. We present confirmatory factor analysis models to explore the structure of psychopathology and wellbeing in early adolescents, using secondary data from a large U.K. sample ( N = 1982). A simple correlated factors structure fitted the data well and revealed that wellbeing was just as related to internalising as this was to externalising symptoms. The classical bifactor solution also fitted the data well but was rejected as the general factor explained only 55% of the total common variance. S -1 models were therefore used to explore general covariance in a more robust way, and revealed that a general internalising distress factor could play an important role in all item responses. Gender and income differences in mental health were also explored through invariance testing and correlations. Our findings demonstrate the importance of considering mental health difficulties and wellbeing items together, and suggestions are made for how their correspondence could be controlled for.

The self-report version of the Strengths and Difficulties Questionnaire is widely used in clinical and research settings. However, the measure’s suitability for younger adolescents has recently been called into question by readability analysis. To provide further insight into the age-appropriateness of the self-report Strengths and Difficulties Questionnaire, readability was assessed at the item level alongside consideration of item quality criteria, its factor structure was analyzed, and measurement invariance between adolescents in Year 7 (age 11-12 years) versus Year 9 (age 13-15 years) was tested. The measure showed a wide range of reading ages, and the theorized factor structure was unacceptable. Measurement invariance was therefore considered for a flexible exploratory structural equation model, and no evidence of differences between age groups was found. Suggestions are made for the measure’s revision based on these findings.

Background Adolescent mental health is a major concern and brief general self‐report measures can facilitate insight into intervention response and epidemiology via large samples. However, measures' relative content and psychometrics are unclear. Method A systematic search of systematic reviews was conducted to identify relevant measures. We searched PsycINFO, MEDLINE, EMBASE, COSMIN, Web of Science, and Google Scholar. Theoretical domains were described, and item content was coded and analysed, including via the Jaccard index to determine measure similarity. Psychometric properties were extracted and rated using the COSMIN system. Results We identified 22 measures from 19 reviews, which considered general mental health (GMH) (positive and negative aspects together), life satisfaction, quality of life (mental health subscales only), symptoms, and wellbeing. Measures were often classified inconsistently within domains at the review level. Only 25 unique indicators were found and several indicators were found across the majority of measures and domains. Most measure pairs had low Jaccard indexes, but 6.06% of measure pairs had >50% similarity (most across two domains). Measures consistently tapped mostly emotional content but tended to show thematic heterogeneity (included more than one of emotional, cognitive, behavioural, physical and social themes). Psychometric quality was generally low. Conclusions Brief adolescent GMH measures have not been developed to sufficient standards, likely limiting robust inferences. Researchers and practitioners should attend carefully to specific items included, particularly when deploying multiple measures. Key considerations, more promising measures, and future directions are highlighted. PROSPERO registration: CRD42020184350 https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020184350.

Internalizing symptoms are the most prevalent mental health problem in adolescents, with sharp increases seen, particularly for girls, and evidence that young people today report more problems than previous generations. It is therefore critical to measure and monitor these states on a large scale and consider correlates. We used novel panel network methodology to explore relationships between internalizing symptoms, well-being, and inter/intrapersonal indicators. A multiverse design was used with 32 conditions to consider the stability of results across arbitrary researcher decisions in a large community sample over three years (N = 15,843, aged 11–12 at Time 1). Networks were consistently similar for girls and boys. Stable trait-like effects within anxiety, attentional, and social indicators were found. Within-person networks were densely connected and suggested mental health and inter/intrapersonal correlates related to one another in similar complex ways. The multiverse design suggested the particular operationalization of items can substantially influence conclusions. Nevertheless, indicators such as thinking clearly, unhappiness, dealing with stress, and worry showed more consistent centrality, suggesting these indicators may play particularly important roles in the development of mental health in adolescence.

Background Universal, school-based behaviour management interventions can produce meaningful improvements in children’s behaviour and other outcomes. However, the UK evidence base for these remains limited. Objective The objective of this trial was to investigate the impact, value for money and longer-term outcomes of the Good Behaviour Game. Study hypotheses centred on immediate impact (hypothesis 1); subgroup effects (at-risk boys, hypothesis 2); implementation effects (dosage, hypothesis 3); maintenance/sleeper effects (12- and 24-month post-intervention follow-ups, hypothesis 4); the temporal association between mental health and academic attainment (hypothesis 5); and the health economic impact of the Good Behaviour Game (hypothesis 6). Design This was a two-group, parallel, cluster-randomised controlled trial. Primary schools (n = 77) were randomly assigned to implement the Good Behaviour Game for 2 years or continue their usual practice, after which there was a 2-year follow-up period. Setting The trial was set in primary schools across 23 local authorities in England. Participants Participants were children (n = 3084) aged 7–8 years attending participating schools. Intervention The Good Behaviour Game is a universal behaviour management intervention. Its core components are classroom rules, team membership, monitoring behaviour and positive reinforcement. It is played alongside a normal classroom activity for a set time, during which children work in teams to win the game to access the agreed rewards. The Good Behaviour Game is a manualised intervention delivered by teachers who receive initial training and ongoing coaching. Main outcome measures The measures were conduct problems (primary outcome; teacher-rated Strengths and Difficulties Questionnaire scores); emotional symptoms (teacher-rated Strengths and Difficulties Questionnaire scores); psychological well-being, peer and social support, bullying (i.e. social acceptance) and school environment (self-report Kidscreen survey results); and school absence and exclusion from school (measured using National Pupil Database records). Measures of academic attainment (reading, standardised tests), disruptive behaviour, concentration problems and prosocial behaviour (Teacher Observation of Child Adaptation Checklist scores) were also collected during the 2-year follow-up period. Results There was no evidence that the Good Behaviour Game improved any outcomes (hypothesis 1). The only significant subgroup moderator effect identified was contrary to expectations: at-risk boys in Good Behaviour Game schools reported higher rates of bullying (hypothesis 2). The moderating effect of the amount of time spent playing the Good Behaviour Game was unclear; in the context of both moderate (≥ 1030 minutes over 2 years) and high (≥ 1348 minutes over 2 years) intervention compliance, there were significant reductions in children’s psychological well-being, but also significant reductions in their school absence (hypothesis 3). The only medium-term intervention effect was for peer and social support at 24 months, but this was in a negative direction (hypothesis 4). After disaggregating within- and between-individual effects, we found no temporal within-individual associations between children’s mental health and their academic attainment (hypothesis 5). Last, our cost–consequences analysis indicated that the Good Behaviour Game does not provide value for money (hypothesis 6). Limitations Limitations included the post-test-only design for several secondary outcomes; suboptimal implementation dosage (mitigated by complier-average causal effect estimation); and moderate child-level attrition (18.5% for the primary outcome analysis), particularly in the post-trial follow-up period (mitigated by the use of full information maximum likelihood procedures). Future work Questions remain regarding programme differentiation (e.g. how distinct is the Good Behaviour Game from existing behaviour management practices, and does this makes a difference in terms of its impact?) and if the Good Behaviour Game is impactful when combined with a complementary preventative intervention (as has been the case in several earlier trials). Conclusion The Good Behaviour Game cannot be recommended based on the findings reported here. Trial registration This trial is registered as ISRCTN64152096. Funding This project was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 10, No. 7. See the NIHR Journals Library website for further project information.