Japan

South Korea

Beijing

Hangzhou

Study population

Over 20 years

Over 19 years

Over 18 years

Over 18 years

Sample

2-stage sampling

3-stage sampling

2-stage sampling

2-stage sampling

Survey mode

Face to face interview

Target number of samples

1800

1000 (quota)

1000 (quota)

1000 (quota)

Completed interviews

894

1002

1000

1011

Survey period

2011/2/2-14

2011/1/13-2/14

2011/10/2-16

2011/10/13-25