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Understanding Impact

How to use your theory of change to develop a measurement and evaluation framework

Did we make a difference? If yes, how so? If not, why not? A measurement framework based on your theory of change can help us all achieve more for the people we serve. Click To Tweet

Did we make a difference? That’s what every charity wants to know. Answering this question can be tricky. It’s hard to collect reliable data about things that have changed. And even if you can, how do you know it was down to you? Would change have happened anyway?

We’ve written this guide for charities who seek to evaluate their work, or measure their impact. Measuring means using data and evidence, both quantitative and qualitative, to gain useful insights about your charity’s work. It’s about understanding whether your project or service made a difference in people’s lives. If yes, how so? If not, why not?

This guide follows on from our Theory of change in ten steps, which we want you to use as the basis of your measurement framework. We explain how to turn your theory of change into a plan for measurement, the five types of data you will need to pay attention to, and how to prioritise what to measure. Finally, we’ve included seven mini-guides below looking closer at specific aspects of evaluation.

Understanding impact is central to our work at NPC, as one of our core consultancy services for charities and funders. Since our 2014 guidance was published, we’ve helped over a hundred clients understand their impact, with many more charities attending a training event or reading our free resources online. Our new guidance builds upon everything we’ve learnt, and draws on our other NPC papers on this topic. We include new advice on how data should be collected, analysed and used, and discuss what an evidence-based learning culture could look like.

To go deeper, come to one of our training events, or get in touch to arrange bespoke support from our team of charity consultants.

Traditional approaches to theory of change can be difficult to apply to campaigning, this NPC guide sets out how to develop a theory of change for campaigning.


A closer look at evaluation techniques:

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1. Quantitative methods

Collecting data from staff and service users, using surveys, online data and social media.

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2. Qualitative data

Hearing from service users about their experience and perceptions in their own words.

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3. Sampling

Concentrating on better data from a small representative group, rather than lots of poor-quality data from lots of people.

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4. Evidence standards

Understanding how evidence standards apply to your intervention.

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5. Research ethics

Understanding the ethical issues that come up when service users are involved as participants in your research.

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Learn how you can support us with money, time or expertise and help us to help maximise impact. NPC

6. Analysing and using data

Making sense of the data you have collected, finding patterns and themes, so you can learn and improve.

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7. Developing a learning culture

Everyone involved in the project should be collecting data, thinking about results and trying to continuously improve.

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We are grateful to the Esmée Fairbairn Foundation for their generous support of this work.

Learn more about theory of change