IntroductionPatients admitted to hospital in an emergency at weekends have been found to experience higher mortality rates than those admitted during the week. The National Health Service (NHS) in England has introduced four priority clinical standards for emergency hospital care with the objective of reducing deaths associated with this ‘weekend effect’. This study aimed to determine whether adoption of these clinical standards is associated with the extent to which weekend mortality is elevated.MethodsWe used publicly available data on performance against the four priority clinical standards in 2015 and estimates of Trusts’ weekend effects between 2013/2014 and 2015/2016 for 123 NHS Trusts in England. We examined whether adoption of the priority clinical standards was associated with the extent to which weekend mortality was elevated, and changes over a 3 year period in the extent to which mortality was elevated.ResultsLevels of achievement of two of the four clinical standards (ongoing review and access to diagnostic services) had small positive associations with the magnitude of the weekend effect in 2015/2016. Levels of achievement of the remaining two standards (time to first consultant review and access to consultant directed interventions) had small negative associations with the magnitude of the weekend effect in 2015/2016. No association was statistically significant. The same pattern was observed in the associations between achievement of the standards and changes in the magnitudes of the weekend effect between 2013/2014 and 2015/2016.DiscussionWe found no association between Trusts’ performance against any of the four standards and the current magnitude of their weekend effects, or the change in their weekend effects over the past 3 years. These findings cast doubt on whether adoption of seven day clinical standards in the delivery of emergency hospital services will be successful in reducing the weekend effect.