Introduction Sleep services in the UK are under pressure with increasing referrals and waits for diagnostic tests. Home diagnostic sleep studies including respiratory polygraphy (RP) and oximetry are recommended by NICE for the diagnosis of Obstructive Sleep Apnoea (OSA).

There is little published data on how often these tests need repeating in real life practice, which is needed to understand aspects of economic evaluations around types of tests and future service recommendations. Did not attend (DNA) data is also poorly understood, although recognised to have links with healthcare inequalities.

Methods All home diagnostic sleep studies recorded on the sleep centre database were retrospectively reviewed from a six month period (Oct 22-March 23) for people booked for RP and oximetry. Numbers of people who needed a repeat study were collected. Reasons for repeat study were inadequate data in the opinion of a senior physiologist including signals missing or study duration too short. It is our practice not to have absolute rules set about data duration or loss of signals, as we may be able to gain useful information from the test to draw conclusion with expert review, because we try to avoid repeating tests if possible.

Results There were 1458 home sleep studies in total booked in 6 months (243 per month), 87% RP. Total DNA rate was 264 studies (22 per month), 18% of the total studies booked. Of 63 studies needing repeat, 4.8% were RP, 8.1% oximetry.

Discussion This data reflects contemporary practice and challenges for a UK sleep service. It is not known what a ‘normal’ failure rate is. More oximetry studies needed repeat. Oximetry is a simpler test for patients to perform and can be provided by a postal delivery to facilitate ease. There may be a selection bias about which test is planned for which patients.