NHS waiting times - diagnostics
Waits for key diagnostic tests
Accredited official statistics
About this release
This quarterly release by Public Health Scotland (PHS) relates to the number of waits for one of eight key diagnostic tests ongoing at 31 March 2025 and the lengths of wait experienced so far. The eight key diagnostic tests are upper endoscopy, lower endoscopy (excl. colonoscopy), colonoscopy, cystoscopy, CT scan, MRI scan, barium studies, and non-obstetric ultrasound. On 31 March 2009, the Scottish Government introduced a waiting time standard that patients waiting for one of eight key diagnostic tests and investigations would wait no longer than six weeks (42 days).
Please note that individual patients are counted more than once if they are waiting for more than one diagnostic test, so the statistics released here do not necessarily reflect the actual number of individuals involved. Therefore, the terminology used in the publication is specifically aimed at preventing misinterpretation of statistics. Please refer to the full report for further detail.
Main points
At 31 March 2025:
- The total waiting list size (number of ongoing waits) for the eight key diagnostic tests combined was 142,747. This represents a 7% (+9,361) increase from the previous quarter-end, when there were 133,386 ongoing waits. This is a change from the month-on-month decrease seen between April 2024 and December 2024. However increases are observed in the same quarter in previous years, which suggests an element of seasonality and is therefore in line with longer-term trends. The latest quarter is 60% higher than the end of March 2019 when there were 89,431 waits ongoing just prior to the outbreak of the Covid-19 pandemic.
- When compared to the previous quarter-end, the three large volume radiology diagnostic tests saw an increase in the number of ongoing waits. Waits for an MRI increased by 23% (+6,103), CT waits increased by 6% (+1,376), and non-obstetric ultrasound showed an increase of 4% (+2,101) compared to the position on 31 December 2024. Waits for barium studies saw a decrease in the number of ongoing waits (-4%, -13).
- Overall, there was a decrease in the size of the waiting list for endoscopy diagnostic tests, from 33,162 at end of December 2024 to 32,956 at end March 2025. This was mainly driven by decreases in waits for colonoscopy (-6%, -665), and lower endoscopy (-6%, -244). However, waits for a cystoscopy increased (+7%, +431) as did waits for an upper endoscopy (+2%, +272).
- Of the 142,747 ongoing waits at quarter-end, 83,573 (58%) had not yet exceeded the six-week standard, an increase from the 53% reported last quarter. 44% of endoscopy tests were ongoing for less than 6 weeks compared to 63% of radiology tests. There was variation across the 8 tests, with the lowest proportion ongoing for six weeks or less being lower endoscopy (32%) and the highest of the high-volume tests being CT (76%).
- There was a decrease in waits over 13 weeks for a radiology test by 10% (-1,796) compared to 31 December 2024. Despite this overall decrease, waits ongoing for longer than 13 weeks for an MRI increased by 9% (+456). Endoscopy tests saw a decrease of 4% for waits over 13 weeks (-600) compared to last quarter. This overall decrease was not seen across all endoscopy tests. The number of waits longer than 13 weeks for a cystoscopy showed an increase of 5% (+169).
- Endoscopy tests account for 99% of all waits over 52 weeks for eight key tests combined (3,796 out of 3,845). Radiology waits over 52 weeks decreased by 50% (-48) compared to the previous quarter, while endoscopy tests also decreased, but to a much lesser proportion, by 2% (-61). The overall decrease for ongoing waits over 52 weeks was not observed across all tests. Two endoscopy tests reported an increase in the number of waits longer than 52 weeks, these tests were upper endoscopy with an increase of 28% (+140), and cystoscopy with an increase of 16% (+137).
Further information
Data from this publication are available from the publication page on our website.
Open data from this publication is available from the Scottish Health and Social Care Open Data platform.
The next release of this publication will be 26 August 2025.
PHS is currently undertaking a review of the statistical publications we produce; all planned care waiting times outputs are being reviewed and this may lead to a change in the content, layout and frequency of future publications. Any substantial changes will be announced ahead of implementation. For more information, please contact us at phs.waitingtimes@phs.scot.
General enquiries
If you have an enquiry relating to this publication, please contact Róisín Farrell at phs.waitingtimes@phs.scot.
Media enquiries
If you have a media enquiry relating to this publication, please contact the Communications and Engagement team.
Requesting other formats and reporting issues
If you require publications or documents in other formats, please email phs.otherformats@phs.scot.
To report any issues with a publication, please email phs.generalpublications@phs.scot.
Older versions of this publication
Versions of this publication released before 16 March 2020 may be found on the Data and Intelligence, Health Protection Scotland or Improving Health websites.