Table 1.
Cohort characteristics.
| Cohort | Ancestry/ethnicity | n | Methylation age | ADHD age | Instrument (age) | Standardized regression coefficients | BACON estimates | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 33% | 50% | 66% | λ | Inflation | Bias | ||||||
| Birth EWAS | |||||||||||
| ALSPAC | European | 714 | 0 | 8, 11, 14, 15 | DAWBA | −0.21 | 0.25 | 0.89 | 1.60 | 1.10 | 0.37 |
| GENR | European | 1191 | 0 | 6, 8,10 | CBCL (6,10), Conners (8) | −0.48 | 0.01 | 0.53 | 1.51 | 1.20 | 0.05 |
| INMA | European | 325 | 0 | 7, 9 | Conners (7), CBCL (9) | −1.37 | −0.40 | 0.43 | 0.80 | 0.87 | −0.19 |
| NEST | Black | 55 | 0 | 5 | BASC | −3.50 | −0.03 | 3.63 | 1.16 | 1.10 | 0.00 |
| NEST | White | 56 | 0 | 5 | BASC | −2.54 | −0.09 | 2.36 | 0.80 | 0.92 | −0.01 |
| PREDO | European | 136 | 0 | 5 | Conners | −1.55 | −0.25 | 1.20 | 1.45 | 0.95 | 0.21 |
| META | – | 2477 | – | – | – | −0.37 | 0.02 | 0.42 | 1.86 | 1.10 | 0.01 |
| School-age EWAS | |||||||||||
| ALSPAC | European | 651 | 7 | 8 | DAWBA | −0.61 | −0.10 | 0.54 | 1.09 | 1.00 | −0.08 |
| GENR | European | 395 | 10 | 10 | CBCL | −0.93 | −0.00 | 0.98 | 1.00 | 0.97 | −0.01 |
| GLAKU | European | 215 | 12 | 12 | CBCL | −0.79 | 0.31 | 1.50 | 0.92 | 0.96 | 0.13 |
| HELIX | European | 1034 | 8 | 8 | CBCL | −0.26 | 0.47 | 1.40 | 1.11 | 0.98 | 0.28 |
| HELIX | Pakistani | 79 | 7 | 7 | CBCL | −1.66 | 1.86 | 5.48 | 0.98 | 0.96 | 0.26 |
| Meta | – | 2374 | – | – | – | −0.24 | 0.14 | 0.62 | 0.96 | 0.92 | 0.14 |
n Number of participants, 33%, 50%, 66% quartiles of regression coefficient distribution, λ inflation of p values, Inflation inflation of p values due to suspected bias, Bias trend toward negative/positive distribution of regression coefficients due to suspected bias.