Newcastle–Ottawa quality assessment scale^*.

^*A study can be awarded a maximum of one star for each numbered item within the Selection and Outcome categories. A maximum of two stars can be given for Comparability. Underlined and quoted phrases are provided in the scale to allow for adjustment to particular studies. Italicized phrases indicate our interpretation of the question relevant to this study.

GC, gastric cancer; ASA, American Society of Anesthesiology classification; BMI, body mass index.