Table 3.

Grade assessment.

Summary of findings:
Effect of bariatric surgery on circulating levels of oxidized low-density lipoproteins in obese patients
Patient or population: obese patients Setting: - Intervention: bariatric surgery Comparison: -
Outcome no. of participants (studies)	Relative effect (95% CI)	Anticipated absolute effects (95% CI)			Certainty	What happens
				Difference
Ox_LDL levels (ox-LDL) assessed with: ELISA/Mercodia/immunodiagnostic/OxiSelect follow-up: range 6 months to 7 years no. of participants: 470 (11 observational studies)	—	The mean ox-LDL levels were 0	—	0 (0 to 0)	⨁⨁◯◯ Lowa,b,c
∗The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval
GRADE working group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different. Low certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect.