Table S2.
Excluded studies and reasons
| Not related to manganese and ADHD (n=4) |
| Konstantopoulos et al5 |
| Hu et al6 |
| Konrad et al7 |
| Han et al8 |
| Meta-analysis (n=2) |
| Rodríguez-Barranco et al9 |
| Scassellati et al10 |
| Review articles (n=3) |
| Zeng et al11 |
| Grandjean and Landrigan12 |
| Lucchini et al13 |
| Not definite diagnosis of ADHD (n=5) |
| Hong et al14 |
| Bouchard et al15 |
| Lucchini et al16 |
| Chan et al17 |
| Ericson et al18 |
| Compare treatment effect of micronutrient but not related to manganese and ADHD (n=1) |
| Rucklidge et al19 |
| Use the same data sample sources of Hong et al2 (n=1) |
| Bhang et al20 |
| Lack of control (n=1) |
| Liu et al21 |
| Collecting manganese when ADHD children were just given birth (n=1) |
| Ode A et al22 |
Abbreviation: ADHD, attention-deficit/hyperactivity disorder.