Title: The impact of different patterns of care on the long-term outcome of adolescent conduct disorder: a mixed methods study comparing multisystemic therapy (MST) and management as usual (MAU)
Funder: Department of Health and Social Care

Abstract: Methods: The original multi-site RCT randomised a nationally representative sample of 684 families to MST or MAU provided by social care and mental health services (exclusions <27%, refusals <10%). 80% were individually followed up at 6, 12 and 18 months with clinical record data available for 100%. The follow-up (objective 1) will extend the primary outcome window to 60 months and carry out an evaluation of a broadened range of outcomes of both MST and MAU to 48 months. We will conduct annual full-blind outcome evaluations up to 48 months post-randomisation. Data on service use will be collected using the Child and Adolescent Service Use Schedule (CA-SUS) (3) and CYPRESS (Children & Young People, Resources, Evaluation and Systems Schedule) (4). Data will be used to characterise services (objective 2) and provide currently lacking information on transitions from child to adult services, identifying correlates of a smooth transition (continuation of appropriate services across the 18-year barrier) and testing the hypothesis that transition is important to relatively better outcomes. A concurrent embedded qualitative study (objective 3) will use semi-structured interviews with families and clinicians and focus groups with adolescents to explore families’ experiences of services and of the transition between services and clinicians’ experience of barriers and facilitators to service implementation. Outcomes: The primary outcome is criminal conviction as registered on the Police National Computer. Secondary outcomes will include (a) antisocial behaviour as indicated by arrest, cautions, self-report, etc, (b) psychiatric problems, (c) education and training outcomes, (d) social network and (e) physical health, together with (f) work adjustment and (g) early (unplanned) pregnancy or fatherhood. The use of services and costs will be monitored. We will estimate the total social, health, educational and criminal justice cost of interventions at 48 months post-randomisation, when we will also identify the key cost and outcome drivers and value for money of the treatments. Analysis: The primary outcome, time to first conviction, will be described by a Kaplan-Meier graph and summarised by the proportion with convictions by 60 months. Cox regression adjusting for pre-specified key predictors will estimate treatment effects. Secondary outcomes up to 48 months post-randomisation will be analysed by linear or logistic regression as appropriate. We will also use random effects models to explore differences between randomised groups in trajectories over time. Data on service use collected using the CA-SUS will be supplemented by a critical pathway analytic approach mapping participants’ journey from initial referral to experience of adult services. Non-parametric clustering techniques will be used to identify typical trajectories across both groups which will be linked with outcome data. The analysis will provide preliminary data concerning service contact associated with favourable or unfavourable outcomes at each point of follow-up. Thematic analysis will be used to integrate qualitative and quantitative data (5).

Lay abstract: Serious juvenile offending is common and probably increasing in the UK. Many of these adolescents commit more crimes in adulthood and are far more likely to have later relationship and health problems and low educational achievement. Their cost to services is 10 times the average with lifetime costs of around £1.5 million per prolific offender (6). Multisystemic therapy (MST) is recognised as probably the best treatment for adolescent antisocial behaviour but it is proprietary, intensive and costly (£15,000 per family). If MST reduces the risk of future criminal behaviour, the expense is justified. Long-term follow-up studies from the USA suggest that treatment costs may be recovered twofold. We cannot assume that US evidence applies to the UK, which spends much more on standard child and adolescent mental and social care. Moreover, outside the USA not all studies have found MST to be more effective than usual treatment and the long-term outcomes of juvenile offending are better in the UK. There are no long-term follow-up studies of adolescents treated with MST in the UK and the wider outcomes (e.g. mental health) of MST participants as they move from adolescence to adulthood are unknown. In order to allocate NHS resources appropriately and ensure that antisocial adolescents receive successful treatment, we need to know whether MST is more beneficial and cost-effective in reducing adolescent antisocial behaviour in the medium to long term than usual services in England. Until now researching this has been impossible due to MST’s cost and the size of sample and length of follow-up required. However, a unique opportunity has now arisen. Three government departments jointly commissioned the largest ever multi-site randomised controlled trial (RCT) of MST. 684 adolescents and their families agreed to take part and 80% of these stayed in the trial. Participants were followed for 18 months. We propose to follow up all trial participants unless they explicitly requested no further contact (only 5% to date) for a further 3.5 years. They will be contacted annually for up to 2.5 years and their criminal convictions recorded for an additional year, covering the period in which most of the costs associated with conduct disorder are incurred. As well as convictions, we will also look at arrests, self-reported crimes and cautions in order to gain a broader understanding of MST’s impact. We will see if the MST group have fewer psychiatric problems in the long term than those who had standard treatments, and monitor participants’ educational progress, work adjustment, social relationships, early (unplanned) pregnancy or fatherhood (also children taken into care), and physical health. We will compare the use of available services by adolescents in the MST programme with services used by those who did not get MST, because savings here could justify MST’s cost. The study will also investigate whether antisocial adolescents cared for by mental health services go on to be cared for by adult services. We will collect information on successful and unsuccessful ways services have been provided, paying particular attention to transitions from child to adult services. Even when services are offered to antisocial adolescents, they are not always taken up. To understand this, we will ask adolescents, their parents and clinicians about their experiences of receiving and delivering MST and other services and will study their views about the developments and changes resulting from treatment.

Research activity codes: 7.1 INDIVIDUAL CARE NEEDS;8.1 ORGANISATION AND DELIVERY OF SERVICES
Health categories: MENTAL HEALTH