Demographic variable

Item

Odd number group

n = 7255

n

Even number group

n = 7255

n

P-value

Respondent

Mother

6951

6951

0.994a

Father

242

240

Grandparent

34

32

Other

6

6

Age of respondent

15 - 19

3

1

0.776b

(Years old)

20 - 24

107

130

25 - 29

916

845

30 - 34

2697

2725

35 - 39

2550

2614

40 - 44

817

780

45 - 49

105

103

≥50

41

39

Family structure

Nuclear family, father working

2373

2421

0.120c

Nuclear family, two incomes

2817

2815

Living together with grandparents, father working

466

474

Living together with grandparents, two incomes

911

852

Single mother

176

193

Single father living together with grandparents

46

25

Single mother living together with grandparents

186

171

Number of children

One

1485

1541

0.777b

Two

3994

3904

Three

1515

1546

Four or more

226

227

Medical region

Chusan

2158

2191

0.661c

Takamatsu

3283

3204

Okawa

639

637

Mitoyo

990

1012

Shozu

145

162

Naoshima (remote island in the Takamatsu medical region)

18

24