Research Excellence Framework (REF) 2021 – A Guide |

Written by Mark Bennett

Research Excellence Framework (REF) 2021

The Research Excellence Framework, or ‘REF’, is the most detailed and extensive assessment of university research in the UK. First carried out in 2014 (and replacing the previous Research Assessment Exercise), it evaluates research performance across 34 different subject areas at each UK university. The results of the REF are used to determine the proportion of public funding allocated to individual universities for research.

For prospective PhD students, the REF 2021 can be a very useful resource… provided you know what to look for.

That’s why we’ve created a convenient and accessible breakdown of the REF 2021 results.

What is the Research Excellence Framework?

The REF is used to determine how much public money is allocated to each UK university in order to fund their research. This funding accounts for the largest proportion of research support received by UK universities.

In addition to determining funding allocations, the REF process ensures universities are accountable for the public investment that supports their research. It also provides a means of benchmarking university research performance for other users… like prospective research students!

Is the REF like a university rankings table?

Not as such. The REF does ‘rank’ university research according to its ability to meet given quality levels, but these are standards specified by the REF, not a direct comparison between different universities and their departments. This means the REF itself isn't a PhD ranking.

How can postgraduates use the REF?

In some ways, the REF result is more useful than a simple university league table. It assesses the specific departments that conduct research and allows you to ‘zoom in’ on the criteria that’s most important to you as a prospective research student: research.

What’s more, the REF provides a detailed breakdown of different aspects of university research, including the quality of academic publications, the positive effect of research in wider society and – most importantly for PhD students – the standard of the departmental units and structures in which research is actually produced, including systems for enabling and supporting successful PhD projects!

What research areas and academic subjects does the REF cover?

All of them! Whatever research topic you’re interested in studying for your PhD and whichever university department you’re looking to do your research in, you’ll be able to access an appropriate REF result. This is because the REF organises university research into 34 different broad subject areas, referred to as ‘units of assessment’.

What is a unit of assessment?

A unit of assessment is really just a category of related subject areas. This allows universities to organise their research units and courses as they see fit, whilst still making sense in the REF system. In practice university researchers submit work to the REF using the most relevant unit of assessment.

How is the REF actually undertaken?

There are three main stages to the REF process: the submission of research, its assessment by expert panels and the publication of results.

Submission stage

This is when universities select the best examples of their research and submit them under the units of assessment that are most appropriate to their work.

Assessment stage

Assessment of research for the REF is undertaken by expert panels. There are two types of expert panel. Most are ‘sub-panels’ assigned to each of the 34 units of assessment. In addition, there are also four main panels, responsible for overseeing the broader implementation of specific REF assessment criteria.

Publication stage

The results of the REF 2021 were published on 12 May 2022. There was a four-month hiatus in the exercise in 2020 because of the coronavirus pandemic, hence the slightly delayed publication of the results.

Who organises the REF?

The REF is administered by different bodies responsible for regulating higher education across the UK:

These are the groups that oversee the distribution of public research funding across the UK.

Is REF funding the same thing as Research Council funding?

No – the four UK higher education Funding Councils are different entities to the seven UK Research Councils and REF funding is different to Research Council funding.

Research Councils fund specific projects (including postgraduate research projects) based on their individual merits. Funding Councils provide ‘block grants’ to support departments within institutions based on their REF performance. This combination of Funding Council and Research Council funding is known as the ‘dual support system’.

What are the REF assessment criteria?

Assessment criteria are one of the most important features of the REF. Research submissions are evaluated according to three specific criteria: Outputs, Impact and Environment. These are then combined to provide an Overall result for each department’s REF score.


Output is the simplest of the three assessment criteria. It measures the quality of academic work produced by a university’s researchers. Up to four research Outputs can be nominated for each academic whose research a university submits to the REF.

Examples of Output include publications like journal articles and book-length studies, as well as other fruits of academic research such as important data sets, new technologies and intellectual property.

Why does Output matter to PhD students?

A university’s Output score for a specific subject area can tell you how successful its academics are at generating high-quality publications. This might offer an indicator of the potential for you to take part in cutting-edge research projects (and the publications they can generate). A high Output score may also mean that your PhD will be supervised by academics who are recognised leaders in their fields.


Impact assesses the positive effects of a university’s research beyond the academy. Impact is assessed using submitted case studies that demonstrate the past effects of a university’s research as well as strategies for ensuring present and future impact.

The REF defines impact as consisting of ‘any effect on, change or benefit to the economy, society, culture, public policy or services, health, the environment, or quality of life, beyond academia’. It’s worth noting that Impact applies to all academic disciplines and subject areas.

For example, medical science research might generate important changes to public health policy, whilst research in an arts and humanities subject area might have an impact on educational outreach and or underpin important exhibitions in public libraries and galleries.

Why does Impact matter to PhD students?

A university’s past success in demonstrating the impact of its research can indicate the opportunity for PhD students to take part in high profile projects and activities outside the university and to do work that is of an immediate and appreciable benefit to society as a whole. As well as being immensely rewarding, this will look excellent on your CV, whatever career path you pursue with your PhD.


Environment is arguably the most important REF assessment criteria from the point of view of prospective research students. It measures the quality of the departments, academic units and research groups in which a university’s research is produced – the ‘environment’ in which you will work as a PhD student.

The quality of a university’s research Environment is assessed based on a range of factors. Of particular importance is evidence demonstrating the ‘sustainability’ and ‘vitality’ of research environments. This can take account of the continuity of research funding as well as the structures in place for the effective support, supervision and training of PhD students.

Why does Environment matter to PhD students?

Of all the REF assessment criteria, Environment is the most directly relevant to prospective PhD students. A university department with a high Environment score will be effectively-organised and sustainably-funded. It is also likely to have a proven track record of supporting postgraduate research projects and good strategies in place to ensure a positive and successful experience for future PhD students… like you!

How are the different assessment criteria used to produce an overall REF result?

The three individual assessment criteria are individually weighted and combined to produce an overall REF result for each subject area:

  • Output is worth 60% of the overall score
  • Impact is worth 25%
  • Environment is worth 15%

Members of the expert panels that assess REF submissions are recruited and appointed at an early stage of the REF process. There are a lot of them, but they fall into two general types:

  • Practising Researchers
  • Research Users

Practising Researchers are usually other academics working in a field appropriate to their assigned subject area. They provide a form of peer-review similar to that used for academic publications.

Research Users are selected from the audience research in a particular subject area is deemed to be of value to. They may also be academics using research data, or they may be representatives of industry, business or policy groups whose work draws on university research.

Quality profiles

A quality profile is the term the REF uses to describe its presentation of the combined result for REF submissions in each subject area. Each item in a submission is ranked according to its quality.

The quality profile for each set of submissions then gives the proportion of its research that meets each ranking level.

The submissions for each subject area are actually given four quality profiles: one for Output, one for Impact, one for Environment and one for an Overall result.

The exact descriptions of standards are tailored to different assessment criteria, but all are ranked from one star to four star:

  • Four star - World-leading
  • Three star - Internationally excellent
  • Two star - Internationally recognised
  • One star - Nationally recognised
  • Unclassified

Ready to delve into the data? You can view REF 2021 results by university here on

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Last Updated: 11 May 2022