It is now 15 years since Bell and Redelmeier published their landmark study demonstrating higher mortality for people admitted to hospital during weekends compared with during the week.1 Examining the records of 3.8 million patients admitted over a 10-year period to emergency departments in Ontario, Canada, this ‘weekend effect’ existed over a range of acute conditions, including 23 out of the 100 leading causes of death.

Since that paper in 2001, over 100 studies have explored the weekend effect, across a range of patient populations and health systems.2 Surprisingly, despite this large number of studies, there remains ongoing debate about whether the weekend effect exists, and if so, what causes it. For example, one recent and highly influential study found higher rates of in-hospital death following admission on Saturday or Sunday compared with Wednesday admissions (HR 1.10 for Saturday and 1.15 for Sunday).3 To read the full article, log in using your NHS OpenAthens details.