Bridging the gap between trials of health interventions and impact on patients: generalizing trial findings using electronic case records systems

Lead Supervisor
Professor Sabine Landau
Professor of Biostatistics
Dept. of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience (IoPPN)
King’s College London

Dr Johnny Downs
NIHR Clinical Scientist (Clinical Senior Lecturer) and Honorary Consultant Child and Adolescent Psychiatrist
Dept. of Child and Adolescent Psychiatry, Institute of Psychiatry, Psychology and Neuroscience (IoPPN)
King’s College London

Industrial Partner
South London and Maudsley NHS Foundation Trust

Project Details

Childhood conduct problems are a costly public health problem. Unaddressed, children with conduct problems have a poor prognosis, and high rates of subsequent criminality. Parenting programmes such as the Incredible Years programme for reducing conduct problems are widely disseminated and many trials have shown it to be effective. However, those planning health care or delivering programmes have long been concerned that trial results may not be generalizable to those who would be offered the intervention. We recently pooled trials in a pan-European study to assess potential inequalities. There were no differential effects by family disadvantage or ethnic minority status (Gardner et al., Lancet Psychiatry: 2019), but child variables (gender, baseline conduct problem severity) that can determine by much child behaviour improves with parent training were found. The existence of such moderating factors raises the possibility that the benefit in the population who would be offered the programme is different. Hence projecting trial findings onto real world populations is important. 

The aim of this project is to explore whether routinely collected data can be used to generalize results from parenting training trials to a South London population. The project will provide an exemplar of the issues that need addressing if routinely collected data are to be exploited to project finding from trials onto real-world populations.

We propose that data routinely collected in the NHS can facilitate assessments of the generalizability of trial results, and thus inform the decision-making process. The non-academic partner of this project, the South London and Maudsley NHS Foundation Trust (SLaM) collects data in an electronic case records system that can be searched using the Clinical Record Interactive Search (CRIS, Perera et al., BMJ Open: 2016). This resource can provide well characterised and representative samples of people who may be offered mental health interventions. We have already ascertained in a pilot study that CRIS can obtain records of at least N=3738 children diagnosed with conduct disorder or oppositional defiant disorder. In addition, the lead supervisor has been involved with the statistical design and analysis of several parenting trials and was responsible for the methodological aspects of the pan-European pooling study. 

Project plan: 

In their first year the student will learn how to use the CRIS interactive system to retrieve information from the electronic case record, establish an updated parenting trials data set and familiarise themselves with the existing literature on estimating intervention effects in a target population. In the second year the students will set up programs that can be run behind the firewall of an electronic medical records system. We envisage using weighting-based estimation (Cole and Stuart, American Journal of Epidemiology: 2010) or outcome-model based estimation (Hartman et al., Journal of the Royal Statistical Society: 2015) and plan to develop the outcome-model approach to provide methods that do not require simultaneous access to the combined patients records (e.g. trial and clinical). In their final year the student will apply these methodologies to investigate what the benefit were if the Incredible Years intervention were made available to all those presenting at SLaM.


Data source 1: South London and Maudsley NHS Foundation Trust (SLaM) electronic case records system, searchable using the Clinical Record Interactive Search (CRIS).

Data source 2: Individual participant data (IPD) from trials of the Incredible Years parenting intervention for reducing child conduct problems. The lead supervisor was involved with the Pan-European IPD meta-analyses referred to above and will follow the process for gaining permission to access this data set for the purpose of the proposed PhD project.

(more details to be provided later)


Electronic case record, clinical trials, real world population, external validity, parenting programmes, child conduct disorder