Table 1 Years of birth and parental age at birth of offspring by categories of offspring zBMI at age 7 years.

From: Instrumental variable analysis using offspring BMI in childhood as an indicator of parental BMI in relation to mortality

Group

Characteristic

Categories of offspring zBMI at age 7

Overall

< − 2

− 2 to > − 1

− 1 to < − 0.5

− 0.5 to < 0.5

0.5 to < 1

1 to < 2

 ≥ 2

All offspring

Offspring

(n = 17,715 girls, n = 18,382 boys)

Birth year

19702

1969

1969

1970

1972

1973

1978

1968 (1962–1985)1

Zheight at age 7

− 0.462

− 0.29

− 0.20

− 0.10

0.08

0.29

0.71

− 0.03

Mothers (n = 19,869)

Birth year

19452

1944

1944

1945

1946

1948

1951

1944 (1937–1952)1

Age at birth (y)

252

25

25

25

25

25

26

24 (21–28)1

Zheight at age 7

− 0.352

− 0.29

− 0.22

− 0.18

− 0.11

− 0.02

0.08

− 0.16

Fathers (n = 16,228)

Birth year

19442

1943

1944

1944

1946

1947

1951

1943 (1937–1952)1

Age at birth (y)

272

27

27

27

27

28

28

26 (23–30)1

Zheight at age 7

− 0.342

− 0.24

− 0.18

− 0.15

− 0.11

− 0.04

0.05

− 0.14

  1. 1 Median (IQR).
  2. 2 Mean.