Combined and intraoperative risk modelling for oesophagectomy: A systematic review

Table 6 Summary of the combination and intraoperative models across the five categories

Model	Ref.	Clinical credibility (out of 7)	Methodological quality (out of 20)	Model performance (overall utility)	External validation	Clinical effectiveness
POSSUM	Copeland et al[46], 1991	4	15.5	Mortality	Yes	No
O-POSSUM	Tekkis et al[48], 2004	4.5	20	No	Yes	No
P-POSSUM	Prytherch et al[47], 1998	4	17	Mortality	Yes	No
E-PASS	Haga et al[49], 1999	3	16.5	No	Yes	No
SAS	Gawande et al[50], 2007	4	16.5	No	Yes	No
eSAS	Janowak et al[26], 2015	4.5	19	No	Yes	No
Modified eSAS	Stroyer et al[27], 2017	4.5	18	No	Yes	No
Yoshida score	Yoshida et al[28], 2015	5	16.5	No	No	No
Xi SAS nomogram	Xi et al[29], 2020	3.5	19	Major morbidity	No	No
Xi IPF nomogram	Xi et al[30], 2019	4.5	16	Major morbidity	No	No
Huang	Huang et al[31], 2020	4.5	17.5	No	No	No

POSSUM: Physiological and operative severity score for the enumeration of mortality and morbidity; P-POSSUM: Portsmouth physiological and operative severity score for the enumeration of mortality and morbidity; O-POSSUM: Oesophagogastric physiological and operative severity score for the enumeration of mortality and morbidity; E-PASS: Estimation of physiologic ability and surgical stress; SAS: Surgical Apgar score; eSAS: Esophagectomy surgical Apgar score.