Table 3.
The subgroup analysis of studies reporting circulating Mg levels.
| Subgroups | n of studies | SMD (95% CI) | I2 | P-value |
|---|---|---|---|---|
| All studies | 21 | −0.74 (−1.13, −0.35) | 93.6% | 0.000 |
| Methods | ||||
| AAS | 4 | −2.62 (−4.59, −0.66) | 95.5% | 0.000 |
| ICP-AES | 4 | −0.81 (−2.11, 0.49) | 97.1% | 0.000 |
| Spectrophotometry | 6 | −0.93 (−1.74, −0.11) | 94.4% | 0.000 |
| ICP-MS | 5 | 0.01 (−0.24, 0.25) | 44.4% | 0.126 |
| ISE | 1 | −0.30 (−0.71, −0.11) | - | - |
| - | 1 | 0.14 (−0.20, 0.48) | - | - |
| Geographic locations | ||||
| Asia | 12 | −0.88 (−1.39, −0.37) | 92.6% | 0.000 |
| Europe | 8 | −0.61 (−1.36, 0.15) | 95.6% | 0.000 |
| Africa | 1 | −0.21 (−0.54, 0.12) | - | - |
ICP-MS, inductively coupled plasma-mass spectrometry; ICP-AES, inductively coupled plasma-atomic emission spectrometry; AAS, atomic absorption spectrometry; ISE, ion-selective electrode.