Figure 2.

Risk of bias and applicability assessment with QUADAS-2. Domains A-D cover patient selection, index test (i.e., the Baveno criteria), reference standard (i.e., esophagoscopy), and flow and timing, respectively. All domains contain sets of questions concerning risk of bias (columns A1–A3, B1–B2, C1–C2, and D1–D3 in the figure), answered with yes, no, or uncertain denoted by a green tick, a red x, or a blue question mark, respectively; summarized as an overall risk of bias for each domain (columns RoB in the figure; green tick, red x, and blue question mark represent low, high, and uncertain risk of bias). Domains A-C include an applicability item each; green tick, red x, and blue question mark represent low, high, and uncertain concerns regarding applicability, respectively. For further details of the assessment, see Supplementary Appendix 2.