OA: What have we learnt after 15 years of research into the ‘weekend effect’?

BMJ Quality and Safety
 Published Online First 30 November 2016 

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.....

Summary

Untangling the evidence for the weekend effect has proven extremely difficult, and it therefore comes as no surprise that it has generated controversy in some settings. Messy, conflicting evidence is, however, less the exception than the norm when it comes to questions about healthcare quality, and meaningful progress can be made even for these knotty types of problems through the use of quality improvement methods. Actively looking for temporal variation in quality of care, patient safety and outcomes should help ensure that potentially important, systematic inequalities in quality do not persist unnoticed.