A social network analysis approach to assess COVID19-related disruption to substance use treatment and informal social interactions among people who use drugs in Scotland.

AIMS: To assess the extent of Coronavirus-related disruption to health and social care treatment and social interactions among people with lived or living experience of substance use in Scotland, and explore potential reasons for variations in disruption. DESIGN: Cross sectional mixed methods interview, incorporating a social network 'egonet interview' approach asking about whether participants had interactions with a range of substance use, health, social care or third sector organisations, or informal social interactions. SETTING: Five Alcohol and Drug Partnership Areas in Scotland. PARTICIPANTS: 57 (42% women) participants were involved in the study, on average 42 years old. MEASUREMENTS: Five-point Likert scale reporting whether interactions with a range of services and people had gotten much better, better, no different (or no change), worse, or much worse since COVID19 and lockdown. Ratings were nested within participants (Individuals provided multiple ratings) and some ratings were also nested within treatment service (services received multiple ratings). The nested structure was accounted for using cross classified ordinal logistic multilevel models. FINDINGS: While the overall average suggested only a slight negative change in interactions (mean rating 2.93), there were substantial variations according to type of interaction, and between individuals. Reported change was more often negative for mental health services (Adjusted OR = 0.93 95% CI 0.17,0.90), and positive for pharmacies (3.03 95% CI 1.36, 5.93). The models found between-participant variation of around 10%, and negligible between-service variation of around 1% in ratings. Ratings didn't vary by individual age or gender but there was variation between areas. CONCLUSIONS: Substance use treatment service adaptations due to COVID19 lockdown led to both positive and negative service user experiences. Social network methods provide an effective way to describe complex system-wide interaction patterns, and to measure variations at the individual, service, and area level.

Peer effects on health-related behaviours of adolescents in Scotland using social network analysis: a cross-sectional study.

BACKGROUND: Previous research suggests that adolescent norms and behaviours may be influenced by peers. The aim of this study was to investigate social clustering of health outcomes among school friendship groups. METHODS: Cross-sectional surveys were collected from Oct 26, 2022, to March 30, 2023, in four secondary schools in Scotland's central belt, and all Secondary 2 (12-13 years) and Secondary 4 (14-15 years) students were invited to take part. Schools self-selected into the study, between 6% and 27% had a free school meal registration (Scotland average 25%). The survey asked about health and about friendships in school. The outcomes of interest were binary indicators of: mental health and self-esteem using validated scales, smoking, drinking without parents knowing (DWPK), and trying drugs. Ethics approval for the study was given by the University of Glasgow (200190035) and all participants gave consent via an online form. We used Auto-Logistic Actor Attribute Models (ALAAMs) to model the association between features of individuals' social networks and their health outcomes. We specified a model for each health outcome separately including parameters: indegree, outdegree, and simple contagion, and combined using meta-analysis. FINDINGS: Response rate was 74% (n=1097; 50% boys, 46% girls, 4% other). Based on self-report measures, 40% participants had poor mental health, 15% had low self-esteem, 6% smoked regularly, 4% tried drugs, and 18% were drinking without parents knowing. Preliminary unadjusted analysis found evidence of social contagion for mental health. Odds of poor mental health for each additional friend with poor mental health was 1·15 (95% CI 1·05-1·26). There was no evidence of contagion for self-esteem (1·13, 0·95-1·34), smoking (1·14, 0·46-2·82), DWPK (0·88, 0·71-1·10), and having tried drugs (0·91, 0·38-2·19). Some networks had low or zero prevalence of the outcomes, increasing the uncertainty in the pooled estimate for the contagion parameter. INTERPRETATION: A cross-sectional study cannot differentiate between social contagion and selecting similar friends, and low prevalence and social desirability bias might have masked associations. However, the unique combination of social network data with advanced statistical modelling gives initial findings on the potential communicable nature of mental health and health behaviours in adolescence. Preliminary results indicate preventive approaches in schools could benefit from social network methods. FUNDING: Medical Research Council (MRC) and Chief Scientist Office (CSO).

Defining research priorities for youth public mental health: reflections on a coproduction approach to transdisciplinary working.

BACKGROUND: With most mental health problems established during childhood/adolescence, young people must be a key focus of public mental health approaches. Despite the range of factors known to influence mental health, evidence for effective interventions is lacking for this age group. This study aimed to define priorities for future public health intervention-focused research to support youth mental health by engaging with transdisciplinary stakeholder groups. METHODS: Our coproduction approach involved priority-setting workshops with young people, researchers, practitioners and policy-makers. Each workshop focused on three thematic areas: social connections and relationships; schools and other education settings; and key groups at greater risk of mental ill-health, specifically LGBTQ+ and care-experienced young people. Workshop outputs were synthesized to define research priorities. RESULTS: This paper presents the research priorities that were defined through the priority-setting workshops, and our reflections on the coproduction approach to guide future similar activities undertaken by others. Ten priorities for youth public mental health research were defined, covering the following areas: building supportive relationships; whole system approaches; social media; support at times of transition; improving links between different services; development and training for those who support young people; staff mental health; engaging with families; awareness of and access to services; and out-of-school and community settings. CONCLUSIONS: These research priorities can inform future intervention development to support youth public mental health. Our transdisciplinary approach means the identified research priorities are likely to be relevant to young people's experiences and needs, and to fit with the needs of those working in practice and policy to support young people.

COVID-19 pandemic and its impact on social relationships and health.

This essay examines key aspects of social relationships that were disrupted by the COVID-19 pandemic. It focuses explicitly on relational mechanisms of health and brings together theory and emerging evidence on the effects of the COVID-19 pandemic to make recommendations for future public health policy and recovery. We first provide an overview of the pandemic in the UK context, outlining the nature of the public health response. We then introduce four distinct domains of social relationships: social networks, social support, social interaction and intimacy, highlighting the mechanisms through which the pandemic and associated public health response drastically altered social interactions in each domain. Throughout the essay, the lens of health inequalities, and perspective of relationships as interconnecting elements in a broader system, is used to explore the varying impact of these disruptions. The essay concludes by providing recommendations for longer term recovery ensuring that the social relational cost of COVID-19 is adequately considered in efforts to rebuild.

Appraising the Implementation of Complexity Approaches Within the Public Health Sector in Scotland. An Assessment Framework for Pre-Implementation Policy Evaluation.

Complexity approaches have gained international attention as potentially effective strategies to address population health challenges. In light of this, the Scottish government (Scot. Gov.) set the implementation of these approaches as the recommended practice for its public health sector organizations. This study evaluates the opportunity and feasibility of implementing complexity approaches in public health Scotland employees' everyday routine by employing a qualitative study that involves 20 stakeholders, representative of different organizations and roles. We made use of an assessment framework based on Soft Systems Methodology (SSm) and Normalization Process Theory (NPT) comprised of five phases: Phase One defines the boundaries, aims, and goals of the issue under study; Phase Two consists of data collection, drawing on the e-Health Implementation Toolkit (e-HIT); Phase Three involves short presentations and breakout group activities to provide information on the new policy; Phase Four employs system thinking tasks to structure debate and builds shared understanding among participants; Phase Five applies NPT to appraise the organizational position around complexity based on information from the preceding steps. We found two main obstacles to implementing complexity approaches: (1) a lack of a shared understanding of the key concepts in complexity and their practical implications; (2) stakeholders' fear of significant disruption to work routines and power relationships. We recommend addressing these issues with appropriate training and customization of goals and tools that may enable complexity approaches to succeed within the Scottish public health context. Our assessment framework allows the recognition of key mechanisms to support how Scotland's Public Health body can enhance the implementation of complexity approaches. The appraisal framework could be used to study early-stage policy implementation in other contexts.

'It's not 9 to 5 recovery': the role of a recovery community in producing social bonds that support recovery.

AIM: To understand how the social networks of a new recovery community can help sustain recovery, focusing on processes of social identity change, in the context of the wider UK recovery movement. METHODS: A cross-sectional, mixed-methods social network analysis (SNA) of ego-network sociograms to map network transitions, using retrospective measures. Ten men were recruited from a peer-worker programme, in the South Ayrshire Alcohol and Drug Partnership (ADP), West of Scotland. Network measures were compared between two timepoints, just prior to current recovery and the present time. Measures included size and density, closeness of members, and their positive or negative influence, proportion of alcohol and other drug (AOD) using and recovery peers, and extent of separate subgroups. These were complemented with qualitative interview data. FINDINGS: There was a significant transition in network composition, with the replacing of AOD-using peers with recovery peers and a broader transformation from relationships being framed as negative to positive. However, there was no significant transition in network structure, with AOD-using and recovery networks both consisting of strong ties and a similar density of connections between people in the networks. CONCLUSIONS: The transition in network composition between pre-recovery and the present indicates a different set of social influences, while the similarities in network structure indicate that the recovery network replaced the role of the using network in providing close bonds. This helped reduce social isolation experienced in early-recovery and provided a pathway into more structured opportunities for volunteering and employment.

Examining the sources of evidence in e-cigarette policy recommendations: A citation network analysis of international public health recommendations.

BACKGROUND: Public health policies and recommendations aim to be informed by the best available evidence. Evidence underpinning e-cigarettes policy recommendations has been necessarily limited due to the novelty of the technology and the lack of long-term epidemiological studies and trials. Some public health bodies have actively encouraged e-cigarette use whilst others have raised concerns over introducing new health risks and renormalising tobacco smoking. Using citation network analysis we investigated the author conflicts of interest and study funding statements within sources of evidence used by public health bodies when making recommendations about e-cigarette policy. METHODS: We conducted citation network analysis of public health recommendation documents across four purposively selected diverse jurisdictions: WHO, UK, Australia, and USA. We extracted all citations from 15 public health recommendation documents, with more detailed data collected for influential citations (used in 3+ recommendation documents). We analysed the relationships between the sources of evidence used across jurisdictions using block modelling to determine if similar groups of documents were used across different jurisdictions. We assessed the frequency and nature of conflicts of interest. RESULTS: 1700 unique citations were included across the 15 public health recommendation documents, with zero to 923 citations per document (median = 63, IQR = 7.5-132). The evidence base underpinning public health recommendations did not systematically differ across jurisdictions. Of the 1700 citations included, the majority were journal articles (n = 1179). Across 1081 journal articles published between 1998-2018, 200 declared a conflict of interest, 288 contained no mention of conflicts of interest, and 593 declared none. Conflicts of interest were reported with tobacco (3%; n = 37 journal articles of 1081), e-cigarette (7%; n = 72), and pharmaceutical companies (12%; n = 127), with such conflicts present even in the most recent years. There were 53 influential citations, the most common study type was basic science research without human subjects (e.g. examination of aerosols and e-liquids) (n = 18) followed by systematic review (n = 10); with randomised control trial being least common (n = 4). Network analysis identified clusters of highly-cited articles with a higher prevalence of conflicts of interest. CONCLUSION: Public health bodies across different jurisdictions drew upon similar sources of evidence, despite articulating different policy approaches to e-cigarettes. The evidence drawn upon, including the most influential evidence, contained substantial conflicts of interest (including relationships with e-cigarette and tobacco industries). Processes to explicitly manage conflicts of interest arising from the underlying evidence base may be required when developing public health recommendations.

Detection of Cytomegalovirus in Urine Dried on Filter Paper.

Urine is the best specimen for the diagnosis of congenital cytomegalovirus, but collection and processing of liquid urine are impractical for screening. Urine dried on filter paper was processed by the same convenient, low-cost method used by newborn screening to test blood spots and showed high sensitivity and specificity.

Ruminant Milk-Derived Extracellular Vesicles: A Nutritional and Therapeutic Opportunity?

Milk has been shown to contain a specific fraction of extracellular particles that are reported to resist digestion and are purposefully packaged with lipids, proteins, and nucleic acids to exert specific biological effects. These findings suggest that these particles may have a role in the quality of infant nutrition, particularly in the early phase of life when many of the foundations of an infant's potential for health and overall wellness are established. However, much of the current research focuses on human or cow milk only, and there is a knowledge gap in how milk from other species, which may be more commonly consumed in different regions, could also have these reported biological effects. Our review provides a summary of the studies into the extracellular particle fraction of milk from a wider range of ruminants and pseudo-ruminants, focusing on how this fraction is isolated and characterised, the stability and uptake of the fraction, and the reported biological effects of these fractions in a range of model systems. As the individual composition of milk from different species is known to differ, we propose that the extracellular particle fraction of milk from non-traditional and minority species may also have important and distinct biological properties that warrant further study.

Situating agent-based modelling in population health research.

Today's most troublesome population health challenges are often driven by social and environmental determinants, which are difficult to model using traditional epidemiological methods. We agree with those who have argued for the wider adoption of agent-based modelling (ABM) in taking on these challenges. However, while ABM has been used occasionally in population health, we argue that for ABM to be most effective in the field it should be used as a means for answering questions normally inaccessible to the traditional epidemiological toolkit. In an effort to clearly illustrate the utility of ABM for population health research, and to clear up persistent misunderstandings regarding the method's conceptual underpinnings, we offer a detailed presentation of the core concepts of complex systems theory, and summarise why simulations are essential to the study of complex systems. We then examine the current state of the art in ABM for population health, and propose they are well-suited for the study of the 'wicked' problems in population health, and could make significant contributions to theory and intervention development in these areas.

Feasibility study of peer-led and school-based social network Intervention (STASH) to promote adolescent sexual health.

BACKGROUND: Effective sex education is the key to good sexual health. Peer-led approaches can augment teacher-delivered sex education, but many fail to capitalise on mechanisms of social influence. We assessed the feasibility of a novel intervention (STASH) in which students (aged 14-16) nominated as influential by their peers were recruited and trained as Peer Supporters (PS). Over a 5-10-week period, they spread positive sexual health messages to friends in their year group, both in-person and via social media, and were supported to do so via weekly trainer-facilitated meetings. The aims of the study were to assess the feasibility of STASH (acceptability, fidelity and reach), to test and refine the programme theory and to establish whether the study met pre-set progression criteria for continuation to larger-scale evaluation. METHODS: The overall design was a non-randomised feasibility study of the STASH intervention in 6 schools in Scotland. Baseline (n=680) and follow-up questionnaires (approx. 6 months later; n=603) were administered to the intervention year group. The control group (students in year above) completed the follow-up questionnaire only (n=696), 1 year before the intervention group. The PS (n=88) completed a brief web survey about their experience of the role; researchers interviewed participants in key roles (PS (n=20); PS friends (n=22); teachers (n=8); trainers (n=3)) and observed 20 intervention activities. Activity evaluation forms and project monitoring data also contributed information. We performed descriptive quantitative analysis and thematic qualitative analysis. RESULTS: The PS role was acceptable; on average across schools >50% of students nominated as influential by their friends, signed up and were trained (n=104). This equated to 13% of the year group. Trained PS rarely dropped out (97% completion rate) and 85% said they liked the role. Fidelity was good (all bar one trainer-led activity carried out; PS were active). The intervention had good reach; PS were reasonably well connected and perceived as 'a good mix' and 58% of students reported exposure to STASH. Hypothesised pre-conditions, contextual influences and mechanisms of change for the intervention were largely confirmed. All bar one of the progression criteria was met. CONCLUSION: The weight of evidence supports continuation to full-scale evaluation. TRIAL REGISTRATION: Current controlled trials ISRCTN97369178.

Social Network Research contribution to evaluating process in a feasibility study of a peer-led and school-based sexual health intervention.

There is growing interest in social network-based programmes to improve health, but rigorous methods using Social Network research to evaluate the process of these interventions is less well developed. Using data from the "STis And Sexual Health" (STASH) feasibility trial of a school-based, peer-led intervention on sexual health prevention, we illustrate how network data analysis results can address key components of process evaluations for complex interventions-implementation, mechanisms of impacts, and context. STASH trained students as Peer Supporters (PS) to diffuse sexual health messages though face-to-face interactions and online Facebook (FB) groups. We applied a Multilevel Exponential Random Graph modelling approach to analyse the interdependence between offline friendship relationships and online FB ties and how these different relationships align. Our results suggest that the creation of online FB communities mirrored offline adolescent groups, demonstrating fidelity of intervention delivery. Data on informal friendship networks related to student's individual characteristics (i.e., demographics, sexual health knowledge and adherence to norms, which were included for STASH), contributed to an understanding of the social relational 'building' mechanisms that sustain tie-formation. This knowledge could assist the selection of opinion leaders, improving identification of influential peers situated in optimal network positions. This work provides a novel contribution to understanding how to integrate network research with the process evaluation of a network intervention.

Sensitivity of Dried Blood Spot Testing for Detection of Congenital Cytomegalovirus Infection.

Importance: The sensitivity of dried blood spots (DBS) to identify newborns with congenital cytomegalovirus (cCMV) infection has not been evaluated in screening studies using the current, higher-sensitivity methods for DBS processing. Objective: To assess the sensitivity of DBS polymerase chain reaction (PCR) for newborn screening for cCMV infection using saliva as the reference standard for screening, followed by collection of a urine sample for confirmation of congenital infection. Design, Setting, and Participants: This population-based cohort study took place at 5 newborn nurseries and 3 neonatal intensive care units in the Minneapolis/Saint Paul area in Minnesota from April 2016 to June 2019. Newborns enrolled with parental consent were screened for cCMV using DBS obtained for routine newborn screening and saliva collected 1 to 2 days after birth. Dried blood spots were tested for CMV DNA by PCR at both the University of Minnesota (UMN) and the US Centers for Disease Control and Prevention (CDC). Saliva swabs were tested by CMV DNA PCR at the UMN laboratory only. Newborns who screened positive by saliva or DBS had a diagnostic urine sample obtained by primary care professionals, tested by PCR within 3 weeks of birth. Analysis began July 2019. Exposures: Detection of CMV from a saliva swab using a PCR assay. Main Outcomes and Measures: Number of children with urine-confirmed cCMV and the proportion of them who were CMV positive through DBS screening. Results: Of 12 554 individuals enrolled through June 2019 (of 25 000 projected enrollment), 56 newborns were confirmed to have cCMV (4.5 per 1000 [95% CI, 3.3-5.7]). Combined DBS results from either UMN or CDC had a sensitivity of 85.7% (48 of 56; 95% CI, 74.3%-92.6%), specificity of 100.0% (95% CI, 100.0%-100.0%), positive predictive value (PPV) of 98.0% (95% CI, 89.3%-99.6%), and negative predictive value (NPV) of 99.9% (95% CI, 99.9%-100.0%). Dried blood spot results from UMN had a sensitivity of 73.2% (95% CI, 60.4%-83.0%), specificity of 100.0% (100.0%-100.0%), PPV of 100.0% (95% CI, 91.4%-100.0%), and NPV of 99.9% (95% CI, 99.8%-99.9%). Dried blood spot results from CDC had a sensitivity of 76.8% (95% CI, 64.2%-85.9%), specificity of 100.0% (95% CI, 100.0%-100.0%), PPV of 97.7% (95% CI, 88.2%-99.6%), and NPV of 99.9% (95% CI, 99.8%-99.9%). Saliva swab results had a sensitivity of 92.9% (52 of 56; 95% CI, 83.0%-97.2%), specificity of 99.9% (95% CI, 99.9%-100.0%), PPV of 86.7% (95% CI, 75.8%-93.1%), and NPV of 100.0% (95% CI, 99.9%-100.0%). Conclusions and Relevance: This study demonstrates relatively high analytical sensitivity for DBS compared with previous studies that performed population-based screening. As more sensitive DNA extraction and PCR methods continue to emerge, DBS-based testing should remain under investigation as a potential low-cost, high-throughput option for cCMV screening.

New psychoactives within polydrug use trajectories-evidence from a mixed-method longitudinal study.

AIMS: To provide public health-related research evidence on types and usage patterns of new psychoactive substances (NPS), developmental pathways into NPS and decision-making factors for, and associated harms of, NPS use. DESIGN: Three-phase mixed-methods design, including a latent class analysis (LCA) of the longitudinal Belfast Youth Development Study (BYDS), a narrative analysis of interviews with NPS users and a three-step approach manual method modelling using regressions to reveal classes of substance use and their associated predictors and outcomes. SETTING: Northern Ireland. PARTICIPANTS: A total of 2039 people who responded to the questions on 'ever use' of the drug variables included at wave 7 (aged 21 years) of the BYDS. Eighty-four narrative interviews with NPS users. MEASUREMENTS: Categories of drug use identified by LCA. Predictors and outcomes included measures of family, partners, peers, substance use, school, delinquency and mental health. FINDINGS: A four-class solution provided the best fit for the data: alcohol; alcohol and tobacco; alcohol, tobacco and cannabis; and polydrug (the latter including NPS). The qualitative analysis yielded a taxonomy that distinguished how NPS operate within a wider range of drug repertoires from experimental to problematic. CONCLUSIONS: In Northern Ireland, new psychoactive substances appear to be a feature of broader polydrug use rather than a standalone class of drug use.

Management of spontaneous intracranial hypotension: a series of 31 cases over 15-years with a challenging outlier.

Spontaneous intracranial hypotension (SIH) has been classified as a triad of postural headache, low CSF opening pressure (below 60mmH20) and diffuse pachymeningeal gadolinium enhancement on MRI. SIH is due to a non-iatrogenic defect in the dura somewhere along the neuraxis (usually in the spine). The resultant leak depressurizes the system and undermines the buoyancy-providing quality of CSF. In many cases the site of leak is not identified. Epidural blood patch (EBP) is a well-established treatment of SIH but is not always effective. We retrospectively analysed thirty-one cases of SIH who required at least one EBP. They were managed over a fifteen-year period at a single institution. EBP resulted in a significant improvement in headache for 77% of patients. We report in more detail on a particularly challenging outlier where severe SIH resulted in coma. Serial epidural blood patches, burr hole evacuation of chronic subdural haematomata, and infusion of 0.9% NaCl via an intradural spinal catheter were all required to enable long-term recovery.

An N-of-1 study of daily alcohol consumption following minimum unit pricing implementation in Scotland.

BACKGROUND AND AIMS: Within the context of Scotland's policy change to implement a minimum unit price (MUP) per unit of alcohol sold in licensed premises, this study used an N-of-1 design to assess between-person differences in the psychological and social factors associated with daily alcohol consumption. DESIGN AND SETTING: A mixed-methods approach combined N-of-1 observational studies, comprising daily surveys followed by qualitative social network interviews (not reported here). Peer researchers with lived experience of substance use were involved in the study design and fieldwork was conducted in towns and rural areas in the East of Scotland. PARTICIPANTS/CASES: Twenty-five adults with current or recent history of alcohol dependence recruited for three 12-week waves: 11 in wave 1 (pre-MUP), 11 in wave 2 (pre- and post-MUP) and three in wave 3 (post MUP). MEASUREMENTS: Gender, age, alcohol and other drug use history. Daily surveys for 12 weeks captured information about factors in the last 24 hours, e.g. amount and type of alcohol consumed, stress, social contact. FINDINGS: Each participant was in the daily survey for a mean of 64 days [standard deviation (SD) = 42; median = 59], with a response rate of 48%; 15 participants provided sufficient data for analysis. Factors related to daily alcohol consumption differed between individuals. Models suggested that some individuals with high initial consumption reduced drinking after MUP, but explanatory factors differed, e.g. changing motivation was important for some, while alcohol availability was important for others. CONCLUSIONS: Adapting N-of-1 methods for an observational study uncovered differences in alcohol consumption change before and after minimum unit pricing implementation in Scotland, evidence of individual differences in the factors relating to alcohol consumption patterns and some evidence that post-MUP consumption changes may be related to changing psychosocial factors.

Mental health disorders and adolescent peer relationships.

RATIONALE: Mental health disorders often arise during adolescence, with disruptive behavior disorders and anxiety disorders among the most common. Given the salience of peer relationships during adolescence, and research suggesting that mental health disorders negatively impact social functioning, this study uses novel methodology from social network analysis to uncover the social processes linking disruptive behavior disorders and anxiety disorders with adolescent friendships. In particular, the study focuses on peer withdrawal, peer popularity, and peer homophily in relation to both disorders. METHODS: Data come from 15-year old students in four Scottish secondary schools (N = 602). Diagnoses of disruptive behavior disorders and anxiety disorders were produced using the Diagnostic Interview Schedule for Children, and peer relationship data were obtained through a friendship nomination survey. Exponential random graph models were used to estimate the probability of peer withdrawal, peer popularity, and peer homophily based on each disorder. RESULTS: Results demonstrated that adolescents with disruptive behavior disorders were more popular than their peers without disruptive behavior disorders (OR: 1.47, CI: 1.20, 1.87). Friendship was also more likely between two adolescents both with or both without disruptive behavior disorders (OR: 1.26, CI: 1.07, 1.47), demonstrating peer homophily. There was no evidence that anxiety disorders were related to adolescent peer relationships. CONCLUSIONS: Findings from this study suggest that disruptive behavior disorders may be socially rewarded (e.g., peer popularity) and socially clustered (e.g., homophily), whereas anxiety disorders show no such trends. Thus, intervention efforts must account for the peer social status that may be gained from engaging in disruptive behavior during this developmental period. Further, given that similarity in DBD status is associated with an increased likelihood of friendship, adolescents are likely to be surrounded by peers who reinforce their behaviors.

School bonding and ethos in trajectories of offending: Results from the Belfast Youth Development Study.

BACKGROUND: Aspects of the school environment, such as school attachment levels, are linked to adolescent offending. Previous research has not clarified whether a school- or individual-level intervention approach to improving pupil school attachment and commitment is most likely to reduce adolescent offending. AIM: The present study assessed the impact of individual- and school-level variables on offending behaviour from ages 14-16 years. SAMPLE: The participants were 4,049 young people from 42 mainstream schools who took part in the Belfast Youth Development Study. METHOD: Multilevel modelling was used to examine the relative influence of individual- and school-level variables on offending behaviour in adolescence. RESULTS: Pupils who had high levels of school commitment and attachment and were involved in fewer fights at age 13 reported lower levels of offending at age 14 years. Differences between schools accounted for 7% of the variation in offending. Lower individual-level commitment was associated with higher initial levels of offending at age 14 if the school-level ethos was of higher commitment. Lack of safety at the school level appeared to be detrimental for young people not exposed to socio-economic deprivation. CONCLUSIONS: Individual-level targeted interventions are likely to be a more cost-effective approach of reducing offending behaviour in adolescence. Additional, albeit smaller, reductions in offending levels could be achieved through school-level interventions in some school types (e.g., deprived areas).