Skip to content

National Audit for Small Animal Neutering

Image of a cat being spayedThe National Audit for Small Animal Neutering (NASAN) is a free audit that allows veterinary teams to measure post-operative complication rates for the neutering of small animals.

The audit template combines practice data, and displays overall results, but also breaks down the analysis by complication and species. By collecting this donated data, NASAN provides a system to measure national benchmarks for the outcomes of canine, feline and rabbit spays and castrations. 

Submit your data

Download the NASAN Spreadsheet [XLSX 80KB]

Submit your data


What is the NASAN?

The National Audit for Small Animal Neutering (NASAN) is a national audit that collects data on post-operative complications of neutering of dogs, cats and rabbits.

Back to top

Who runs the NASAN?

The NASAN is run by RCVS Knowledge, an independent charity sitting at the heart of our professions, to help advance the quality of veterinary care for the benefit of animals, the public and society. 

RCVS Knowledge is a separate organisation to the RCVS, and it is governed as such by the RCVS Knowledge Board of Trustees. We are a separate data controller to the RCVS.

RCVS Knowledge is not a public authority and is therefore not covered by the Freedom of Information Regulations.

Back to top


What data is required to take part in the NASAN?

  • Country of practice (England, Scotland, Wales, Northern Ireland, Republic of Ireland)
  • Practice name (for a certificate to be sent to the practice. This certificate can be used for the Practice Standards Scheme- to show you are taking part in a national audit for benchmarking purposes)
  • Date of surgery
  • Type of surgery (to choose from)
    • Cat castrate.
    • Cat spay.
    • Dog castrate.
    • Bitch spay.
    • Laparoscopic bitch spay.
    • Rabbit castrate.
    • Rabbit spay.
  • Complication/ follow up (to choose from)
    • Lost to follow up.

    • No abnormality.

    • Abnormal – no treatment required.

    • Abnormal – medication required.

    • Abnormal – surgery required.

    • Death of animal.

Back to top

How we define personal information (personal data)

'Personal data' means information which relates to a living person who can be identified from that data (a ‘data subject’) on its own, or when taken together with other data which is likely to come into our possession. This may be for example: a name, an address, phone number, email address or even an IP address. It does not include anonymised data.

This policy applies to all personal data whether it is stored electronically, on paper or on other materials. We will comply with the lawful basis processing requirements under Article 6 of the General Data Protection Regulations (GDPR).

Back to top

What personal data is included with the NASAN?

No personal data is collected for the NASAN. The data submitted does not fall under the remit of the General Data Protection Regulations (GDPR).

When you send your data to the NASAN, your email and practice name will be used to send back your participation certificate. This data is not stored. By sending us the data, and providing an email address, you give us permission to use your email address and practice name in this way.

Back to top

How do we collect your data?

We collect your data when you give it to us directly. This is by sending us your completed NASAN spreadsheet, either by email, or by the submission form.

Back to top

Security of your personal data

We place the highest importance on the securing of your data. We employ industry leading approaches to secure your digital (files and database entries) data. For cyber security reasons we do not publicly disclose the exact nature of the methods/techniques we use to secure your data.

We make every effort to protect its databases against loss, theft, unauthorised access, disclosure, copying, unauthorised use or modification. 

We only allow those of our employees who require access to such information in order to fulfil their duties to have such access.
For security purposes we use software programs to monitor traffic to identify unauthorised attempts to upload or change personal data, to screen our system for viruses, or otherwise cause damage to our database.

In addition to a broad range of cyber security provisions across all our systems and information stores, certain sections of our web sites and web applications encrypt your data in transit using SSL and comparable encryption standards.

However, no data transmission over the Internet can be guaranteed to be totally secure. As a result, whilst we strive to protect your personal information, we cannot ensure or warrant the security of any information which you send to us, and so you do so at your own risk.

When we outsource any processes, we require the third party supplier to have appropriate security measures in place and be compliant with the GDPR principles. We require all third parties to respect the privacy of your personal data and to treat it in accordance with the law.

Third-party service providers should process your data for specified purposes and in accordance with our instructions and should not use your data for their own purposes. They will also be contractually bound by non-disclosure agreements to ensure the security of your data.

If any of your data is to be transferred to another country, we will ensure that suitable safeguards are in place before personal data is shared. We will not transfer, process or store your data anywhere that is outside of the European Economic Area, unless we have a contractual agreement in place that is of an equivalent standard to GDPR.

Back to top

What happens to your data?

What do we do with your data?

  • All submitted data is pseudo-anonymised and analysed on an annual basis. This report is made publicly available to allow practices to compare their complication rates against the national benchmark.
  • All submitted data is kept in a secure, password protected location.
  • Your practice name will be used to generate a certificate for participation. This certificate can be used as evidence if you are taking part with the Practice Standards Scheme, and will be sent to the email address you use to send the data in.

What don’t we do with your data?

  • We won’t share your data in any other way than previously described.
  • We won’t run reports or publish data with any practice details in.
  • We will not disclose your data to third parties. 

How long is your data kept for?

The data is kept indefinitely as part of a national benchmark.

Back to top

Taking part

What are the benefits of taking part in the NASAN?

You will contribute to a national benchmark and fulfil your professional responsibility to help support the improvement of patient care.

You can see how your organisation is performing when compared to data that includes other practices and practice groups, and recognise if you are an outlier in providing outstanding care, or need to make improvements.

Back to top

What does it cost?

The NASAN is free to use.

Back to top

What format does the data need to be in?

Any spreadsheet including Excel, Power BI, Google Docs, or Numbers. If you are not sure if the program you use is compatible, please get in touch at [email protected]

Data should be sent as individual procedures.

Back to top

How regularly should data be sent?

Monthly, quarterly or an annual basis.

Back to top

How should data be sent?

Data can be sent in one of two ways.

  1. Fill out the submission form
  2. Data can be sent in bulk to the QI Project Manager at RCVS Knowledge (Details below).

Back to top

How can I send bulk data from my organisation?

Before sending any bulk data. Please get in touch with [email protected] to sign a Data Sharing Agreement and to set up your organisations SharePoint folder.

  • Only one person will be able to have access to the SharePoint folder. This should be a QI Lead of your organisation (or a similar role).
  • Only the QI Project manager at RCVS Knowledge will have access to this folder.
  • Any personal data should be removed from the bulk data before adding it to the SharePoint folder.
  • Data can be sent in csv file/.xlx./pbix
  • The file should be named with the date span that the data covers. E.g. 070421_040921
  • Once data is added to the SharePoint folder, email the QI Project Manager at RCVS Knowledge who will confirm receipt of the data.

Further information on this process is detailed in the Data Sharing Agreement. 

Back to top

How will potential duplicate data be managed?

On submission, the user will be asked if they are part of a corporate group.

If they are part of a corporate group that routinely sends in neutering data (via bulk data), then their individual practice data will be accepted for the purpose of a participation certificate, however, will not be added to the annual benchmark report.

Back to top

Submit your data

Download the NASAN Spreadsheet [XLSX 80KB]

Submit your data

How to complete the NASAN spreadsheet

  • Download the spreadsheet, then save it on your computer somewhere you’ll be able to find it again easily.
  • Identify the animals in your practice that have had a spay or castrate within a set period.
  • Enter the information on the spreadsheet, including:
    • Date of surgery
    • Which procedure
    • What the outcome was, choosing from:
      • Lost to follow-up: patients that do not return to the practice when a repeat check-up was expected.
      • No abnormality present: healed as normal.
      • Abnormal but no treatment necessary: abnormal healing that resolved without any treatment.
      • Abnormal requiring medical treatment: abnormal healing that required extra treatment, on top of your routinely prescribed postoperative treatment.
      • Abnormal requiring surgical intervention: abnormal healing that required surgery.
      • Fatality of animal: the patient died, either in the peri- or post-operative period.
  • If you record your practice name on the spreadsheet, you will receive a certificate for your participation. This is ideal for the RCVS Practice Standards Scheme. 
  • When you’ve finished, save the spreadsheet, and submit it.
  • Talk about the results at your next team meeting.
  • Check out the resource hub for access to evidence and resources that can help you improve your outcomes.
  • This video shows how to complete the NASAN.

Use this poster to display your National Audit for Small Animal Neutering results and compare them with your practice and the national benchmark. You can use this poster as a focal point for your Quality Improvement discussions. This poster is designed to be professionally printed, and laminated, on A2 paper. [PDF 73KB] (November 2022)

Back to top

National neutering benchmarks

You can download a benchmark report and infographics below. 

NASAN infographic

NASAN infographic thumbnailWe encourage sharing this information. You must give credit for using this resource, by citing, for example:

RCVS Knowledge. 2022. National Audit for Small Animal Neutering 2021 Benchmark Infographic. Available at:

You should not edit this resource in any way.
This work is licensed under Attribution-NoDerivatives 4.0 International.

Back to top

NASAN benchmark report

We encourage sharing this information. You must give credit for using this resource, or any data from it, by citing, for example:

RCVS Knowledge. 2022. National Audit for Small Animal Neutering 2022 Benchmark Report. Available at:

You should not edit this resource in any way.
This work is licensed under Attribution-NoDerivatives 4.0 International.

NASAN report thumbnailWe encourage sharing this information. You must give credit for using this resource, by citing, for example:

RCVS Knowledge. 2022. National Audit for Small Animal Neutering 2021 Benchmark Report. Available at:

You should not edit this resource in any way.
This work is licensed under Attribution-NoDerivatives 4.0 International.

Back to top


Resource hub

Now you have your audit results, what next? We have compiled evidence, articles, resources and case examples from the profession to help you in your journey to improve your patient outcomes.

Access the resource hub.


Back to top

RCVS Knowledge would like to thank all practices that have submitted data. Without their participation, standards setting would not be possible. If you require any further assistance with submitting data or you have any concerns or comments on this subject, please contact [email protected]