The PETAL Programme (NIHR ID: NIHR200120)

Personalised treatment packages for adults with learning disabilities who display aggression in community settings (PErTA-Ld), is a NIHR funded 66 month programme, which began in April 2020.


The aim of the 66 month programme is to develop and test a personalised treatment package for adults with learning disability who display aggression.

We will:

1. Review the evidence about which psychosocial treatments for aggression work for people with learning disabilities and for other client groups. We will review the manuals and how they are delivered.

2. Use routinely collected NHS data to assess how adults with learning disability who display aggression respond to treatments. This will enable us to better understand what influences patient outcomes and to inform the design of the personalised treatment package.

3. Talk to adults with learning disability who have good outcomes, and those with poorer outcomes, their family or paid carers and professionals. With those who report things went well we will ask why they thought that was so. Where it did not go so well we will explore what might have been more helpful.

4. Use the findings from 1 and 2, and work with adults with learning disability, carers and professionals, to develop a personalised treatment package. It may include support strategies for family carers, focus on person centred care for paid carers to understand and manage aggression better, develop skills in the adult with learning disability to identify goals, or signpost for practical help with social care. We will write a manual and train NHS staff in how to deliver the personalised treatment package and will test whether it is practical and acceptable, making changes if needed.

5. Find out, in a large trial, whether the personalised treatment package makes a positive difference to the health and quality of life of adults with learning disability and how cost effective it is.

We will focus on public involvement throughout the programme. We will include adults with learning disability and family carers experts by experience throughout the research and in all oversight groups.

We will explore how to improve the delivery of the package in services so that it can be rolled out if effective. We will write a report and will promote our work through publications, conferences, social media, policy briefings and .practical resources for NHS professionals.


  1. To identify key features of adults with learning disabilities, their family and paid carers and the environment that respond differentially to existing treatments for aggression

  2. To identify individual and contextual predictors of aggression to inform the treatment package content
  3. To conduct a qualitative study to deepen understanding of the reasons for good or poor outcomes for aggression and quality of life
  4. To work with family and adults with learning disability (experts by experience) to develop the personalised treatment package for aggression and to test its feasibility
  5. To conduct a randomised controlled trial with an internal pilot to test the clinical and cost effectiveness of the personalised treatment package. 

4 workstreams: 

WS1 (months 1-16): A rapid realist review (RRR) to examine why, for whom, and in what circumstances complex intervention programmes for aggression are most successful including key components of the interventions and the setting within which they are delivered. Up to 40 qualitative interviews with adults with mild learning disability, family carers, paid carers, health and social care professionals and service managers, to examine experience of care and measures of success or failure of interventions and care.

WS2: (months 1-12): a retrospective cohort study using the Clinical Record Interactive Search database to examine predictors of contacts with crisis services including admissions over 8 years.

WS3 (months 16-24): co-design of intervention with adults with learning disability, their family and paid carers and professionals to co-design the personalised treatment package and its training manual; feasibility testing. Lead in for cluster RCT: months 20-26

WS4 (months 26-62): A cluster randomised controlled trial (n=410) in 3 UK countries (England, Scotland and Northern Ireland) to test the clinical and cost effectiveness of the personalised treatment package; process evaluation.