Table 2 For each twin type, percentage of current smokers at each survey wave and percentage with any smokers among their friends by smoking status, at each survey wave (base: individual twins)

From: Does smoking among friends explain apparent genetic effects on current smoking in adolescence and young adulthood?

 

Twin type

 
 

MZ

DZS

DZO

Total

Current smokers

 Wave 1 (%)

12

14

17

14

 Wave 2 (%)

20

25

26

23

 Wave 3 (%)

26

31

31

29

 Wave 4 (%)

19

21

24

20

Any smokers among friends

Wave 1

    

 Non-smokers (%)

24

30

27

26

 Current smokers (%)

90

94

84

90

 Total (%)

32

39

37

35

Wave 2

    

 Non-smokers (%)

46

43

48

46

 Current smokers (%)

93

91

91

92

 Total (%)

56

54

59

56

Wave 3

    

 Non-smokers (%)

51

49

49

50

 Current smokers (%)

90

88

86

88

 Total (%)

61

61

61

61

Wave 4

    

 Non-smokers (%)

44

47

45

45

 Current smokers (%)

90

91

92

91

 Total (%)

53

56

56

54

  1. DZO=opposite-sex dizygotic or fraternal twins; DZS=same-sex dizygotic or fraternal twins; MZ=monozygotic or identical twins.
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