Table 3.

Summary of findings table.

Type 2 diabetes compared to healthy controls
Patient or population and Exposure: Individuals with T2D Comparison: Healthy controls (normoglycaemics) Outcome: Hepcidin levels and iron overload
Outcomes	Absolute effects∗ (95% CI)		Relative effect (95% CI)	№ of participants (studies)	Certainty of the evidence (GRADE)	Comments
	Risk with control	Risk in T2D patients
Iron regulator proteins Measured by the levels of hepcidin	-	The standardised MD in the exposure group was 0.07 higher (-0.30 to 0.44)	-	2 620 (11 observational studies)	⨁⨁OO LOW
Iron profiles Measured by haemoglobin levels	-	The mean level in the exposure group was -0.23 mg/dl lower (-0.46 to -0.01)	-	2 320 (8 observational studies)	⨁⨁OO LOW

CI: Confidence interval; MD: Mean difference; OR: Odds ratio; NE: Not estimable.

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.

^∗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).