Table 2 Prenatal exposure to maternal cigarette smoking (PEMCS) and demographic characteristics, cognitive score and potential mediating factors

 Male sex

98/253 (39%)

95/218 (44%)

1.136

0.287

 Smoking at 26-27 years

80/253 (32%)

97/218 (45%)

8.275

0.004

 Prenatal exposure to alcohol

19/249 (8%)

54/217 (25%)

26.129

<0.001

Birth weight (kg)

3.643

3.497

3.404

<0.001

 Vocabulary

0.079

-0.091

1.842

0.066

 Matrix reasoning

0.054

-0.063

1.273

0.204

 Verbal fluency

0.027

-0.031

0.628

0.530

 Pegboard

0.036

-0.042

0.846

0.398

 Stroop

0.011

-0.013

0.251

0.802

 PAL

0.039

-0.052

0.979

0.328

 MSST

-0.049

0.052

1.036

0.301

 Inattention and hyperactivity (SWAN) z-score

0.170

-0.203

3.720

<0.001

 PLEs

69/229 (30%)

74/191 (39%)

3.440

0.064

 Externalizing (YSR) z-score

-0.185

0.208

4.072

<0.001