Magnitude and modifiers of the weekend effect in hospital admissions: a systematic review and meta-analysis.

Objective: To examine the magnitude of the weekend effect, defined as differences in patient outcomes between weekend and weekday hospital admissions, and factors influencing it.

Design: A systematic review incorporating Bayesian meta-analyses and meta-regression.

Data Sources: We searched seven databases including MEDLINE and EMBASE from January 2000 to April 2015, and updated the MEDLINE search up to November 2017.