Table 2.

Studies examining the association between time of birth on patient outcomes.

Author(s) and year, definition of off-shift	Multisite (no. sites), patient sample size	Outcome(s)	Poor quality outcomes
Nights
Caughey et al. (2008), Evening: 1800–0001, Night: 0001–0700	N, 34,046	Mortality and Apgar scores	N
Badr et al. (2007), Night: 2300–0700	Y (4), 5152	Mortality, asphyxia, neonatal morbidity	Y
Urato et al. (2006), Night: 2301–0759	Registry, 80 cases, 999 controls	Mortality	Y
Gould et al. (2005), Early night: 1900–0059 Late night: 0100–0659	Registry, 3,363,157	Mortality	Y
Luo and Karlberg (2001), Night: 2100–0700	Registry, 2,102,324	Mortality	Y
Stewart et al. (1998), Night: 2100–0859	Registry, 1015	Mortality	Y
Nights and weekends
Bell et al. (2010)*, Early night: 1701–2259, Late night: 0000–0759 Weekend: Sat and Sun	Registry, 11,137	Mortality within 7 and 28 days, short-term morbidity and neurodevelopmental outcomes of low birth weight infants	N
Stephansson et al. (2003)*, Night: 2000–0759, Weekend: Sat and Sun	Registry, 694,888	Mortality	Y

Y, yes; N, no.

^*Analysed nights and weekends separately.