The weekend effect: now you see it, now you don't.

The author reflects on the safety of hospitals at weekends in Great Britain. Topics covered include the development of hospital safety policies based on systematic and dispassionate assessment of evidence, the highlights of the article "Biases in detection of apparent 'weekend effect' on outcome with administrative coding data: population based study of stroke" published in the journal "The BMJ" on May 16, 2016, and other research studies relating to the hospital weekend effect.