Table 1. The American College of Gastroenterology definitions for grading recommendations based off of the GRADE approach.

Definitions from ACG CPGs:	Corresponding grade:
Further research is very unlikely to change our confidence in the estimate of effect. Homogeneous evidence from multiple well-designed randomized (therapeutic) or cohort (descriptive) controlled trials, each involving a number of participants to be of sufficient statistical power. Data derived from multiple randomized clinical trials or meta-analyses. Evidence obtained from at least 1 well-designed and well-controlled randomized controlled trial that has either: a. Cancer end point with mortality or incidence, or b. Intermediate endpoint	High
Further research would be likely to have an impact on the confidence in the estimate of effect. Evidence from at least one large well-designed clinical trial with or without randomization, from cohort or case–control analytic studies, or well-designed meta-analysis. Data derived from a single randomized trial, or nonrandomized studies with limitations. Evidence obtained from well-designed and well-conducted cohort, case-control, or nonrandomized controlled trials that have: a. Cancer end point b. Intermediate end-point	Moderate
Further research would be expected to have an important impact on the confidence in the estimate of the effect and would be likely to change the estimate. Evidence based on clinical experience, descriptive studies, case series, or reports of expert committees. Recommendations are based on level 4 studies, meaning case series or poor-quality cohort studies. Any estimate of effect is very uncertain.	Low