Commissioning decisions should be informed by the best available evidence. This helps to improve outcomes for patients and makes sure that scarce resources are used efficiently and effectively. Likewise, evaluation can help you to consider what works, what doesn’t work and how things can be improved.

What is evaluation?

Evaluation is about judging or comparing the merit or worth of something.

Evaluation can range from being very simple service evaluations to complex evaluative research projects. Each service will require a different approach depending on the purpose of the evaluation, evidence base, stage of development, context of the service, and the resources and timescales for the evaluation.

Evaluations can focus on implementation and learning (formative evaluation), how a service works (process evaluation) and whether it has worked (outcome or summative evaluation) – or all of these aspects over the life cycle of a project. Watch our short videos to learn more.

Watch our video: What is evaluation? 

Watch our video: What should I consider when planning an evaluation? 

Watch our video: Evaluation tools and resources


Theory of Change

What is Theory of Change? What are the benefits? And how do I use it?

The West of England Academy collaborated with NIHR ARC West, Health Innovation South West, Health Innovation Wessex and Natural England to deliver an online workshop to answer these questions. Access the resources from our workshop to improve your understanding of Theory of Change.

Evaluation Online Network

The Evaluation Online Network provides virtual support and guidance on evaluation activity. Since 2018 the Network has been co-led by Health Innovation West of England and the University of the West of England (UWE). Find out more about  the Evaluation Online Network.

Please contact for more information.

The Evidence Repository

This provides a portal for members to share grey literature not published anywhere else with colleagues within the NHS, Public Health, and Universities. Documents can include QI projects, evaluations and evidence summaries. The repository aims to reduce unnecessary duplication and improve sharing across health systems. Find out more, and join our Evidence Repository.

Best practice guidelines

Two sets of best practice guidance on ethics and governance of service evaluation and patient and public involvement (PPI) in evaluation have been developed. This guidance is aimed at anyone conducting service evaluations in health and social care.

For further information and the full guidelines, please visit the NIHR ARC West website.

Other evidence and evaluation partners

Case studies and online toolkits

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Evaluation case studies

Our evaluation case studies illustrate how carrying out a service evaluation can positively influence an improvement project.

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Evaluation toolkit

This online toolkit will help you to consider what works, what doesn’t work and how things can be improved.

Use the toolkit
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Evidence case studies

These case studies illustrate how using an evidence-informed commissioning process can positively impact on health and care services.

Read more

Evidence toolkit

This online toolkit is a complete guide to finding, appraising and applying evidence.

Use the toolkit

Theory of Change

Access resources from our Theory of Change workshop to improve your understanding.

Read more