Table 1 Cohort characteristics.

From: Association between DNA methylation and ADHD symptoms from birth to school age: a prospective meta-analysis

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

  1. 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.