Table 2 Features of included studies and quality assessment
Study | Year | Country | Design | Primary outcome | NOS score |
|---|---|---|---|---|---|
Speggiorin et al. [17] | 2015 | UK | Single center, retrospective study | Mortality and complications | 6 |
Kugelman et al. [18] | 2005 | USA | Single center, retrospective cohort study | Mortality and complications | 8 |
Knight et al. [20] | 1996 | USA | Multicenter, retrospective cohort study | Mortality and complications | 8 |
Chevalier et al. [19] | 1993 | France | Multicenter, retrospective study | Mortality and complications | 6 |