NHS waiting times - diagnostics
Waits for key diagnostic tests

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

This chart shows the total number of ongoing diagnostic waits and percentage of waits that were ongoing for six weeks or less, from month ending January 2022 to month ending March 2025. The top shaded area shows a general downward trend in the number of radiology waits across the time period, although an increase has been recorded since the end of 2024. The bottom shaded area shows a steady trend in the number of endoscopy waits since January 2022. There are three lines on the graph, representing the percentage of waits that have been ongoing for six weeks or less at the end of each month. The top dotted line shows that the percentage of radiology waits not having exceeded six weeks has been relatively stable with some seasonal variation, but recent months have shown an increase. The percentage of radiology waits that have not yet breached the six week target in March 2025 is 63%. The trend is similar in the middle solid line which shows the same percentage for all diagnostic waits. The percentage of all diagnostic waits ongoing for six weeks or less has been steady with some seasonal variation, with some increases in recent months. The percentage at 31 March 2025 is 58.5%. The bottom dotted line shows the percentage of waits ongoing for six weeks or less for endoscopy tests. As with the other two lines, the trend is broadly stable through the time period, with some seasonal variation, and increases are again seen in recent months. However, the percentage has been consistently lower than radiology, with the percentage at the latest quarter end being 43.8%.

Close

Trend in ongoing waits and percentage of waits ongoing for six weeks or less at month-end, by test, NHSScotland, 31 January 2022 to 31 March 2025.

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.​