Table 2. The OR of the association between Se levels and the presence of DM by cut-off levels of Se of the highest group.

Cut-off value of Se level of highest group	No. of studies	OR (95% CI)	Heterogeneity (I2), %
<100 μg/L	6	1.90 (1.23–2.93)	74
100–120 μg/L	2	4.06 (2.67–6.18)	0
>120 μg/L	4	2.46 (1.48–4.10)	79

OR, odds ratio; Se, selenium; DM, diabetes mellitus; CI, confidence interval.