Simulation Modelling

Sim:pathy is a discrete event simulation modelling tool, designed for the particular needs of mental health services. By highly detailed analysis and forecasting of capacity and demand, Sim:pathy enables you to ensure that services are:

  • Safer, ensuring early and local access to services for people needing it – reducing out of area treatments to an absolute minimum – and improving recovery to help people stay well.
  • Financially sustainable, making best use of the money and workforce available.
  • Effective, more responsive to patients’ preferences, and better able to handle future demand.

A Sim:pathy project will leave you with:

  • a sustainable and deliverable service model;
  • a detailed, clearly structured, and robustly evidenced understanding of the nature and volume of services which you should offer – not only within acute mental health services, but also in the upstream, downstream, and related services;
  • a process which has engaged a wide variety of people, and therefore prepared an excellent base for subsequent implementation; and
  • a clear case to present to local stakeholders about your plans and required service and resource changes.

Our approach to such work is based on strong engagement with client organisations and their stakeholders – and on formal discrete event simulation modelling. This method ensures that the full range of variation in real patient flows is captured, and that the future model allows for highly detailed differences between patient cohorts and service types. Other, less realistic tools and approaches tend to assume that all patients behave like the “average” patient – this is unrealistic, and leads to misleading results.

We identify how patients currently move through services – where they are referred from, and where they are discharged to, and we determine the probability of each of these events within local services. This can be broken down by care cluster, by age, by ethnicity, or by any other means of subdividing patients, which is locally important.

Within a tailored computer-based model, we create a structure of teams and services which matches current reality. Patients, over a period of months or years, then present to services. These patients are generated as having the characteristics, and at the variable frequencies, which are typical of the way local services currently work.

This then forms the basis for detailed engagement with managers and clinicians across services – identifying options, modelling scenarios, considering ideas in combination, testing acceptability, beginning to think about implementation approaches. This is done by 1-1 conversations, small group meetings, larger workshop-style events, all planned according to your needs and preferences.

We capture and record the ideas which seem to work best, and testing these many times over to ensure that they are likely reliably to be effective.

The outcomes are highly detailed, typically including:

  • for every scenario planned or contemplated, a robust forecast of its effect on waiting times, overspill, and capacity pressures;
  • the effects of scenarios in combination, not just singly;
  • the effects of demographic change; and
  • for every service line, the caseloads they should expect to be carrying.

We have developed substantial expertise in the field of simulation modelling in mental health care, with an unrivalled combination of both technical skills, and understanding of the ways in which mental health services actually work in practice. Examples of recent modelling projects include:

  • Ongoing projects in Hertfordshire, Norfolk, Suffolk, Birmingham, and Pennine Care, in each case examining whole-system strategic change across services.
  • A county-wide review of the acute pathway in Cumbria, as part of local success regime work.
  • A substantial project to establish the needs for both acute beds and supporting mental health services across South West London.
  • A county-wide review of all mental health services in Nottinghamshire.
  • A simulation modelling review of all mental health services for adults in each of Bath and North East Somerset, Surrey, and Derbyshire.
  • An impact assessment of service redesign in Birmingham, supported by simulation modelling.
  • A simulation modelling review of all mental health services for adults of working age in Bradford.
  • A qualitative and quantitative review of mental health services for adults in Leicestershire.
  • Development of a plan for primary/secondary care redesign in South Essex.
  • A modelling review of plans to redevelop medium secure services in Merseyside.
  • A detailed value for money review of the delivery of mental health services in Croydon, followed by simulation modelling of changes to pathways.


Please contact James Fitton at james.fitton@mentalhealthstrategies.co.uk for more information.