Table 1 Descriptions and characteristics of dependent and independent variables

Smoking frequency

1. Daily

1. 9.4%

1. 58.4%

2. Weekly

2. 3.7%

2. 13.6%

3. Monthly

3. 2.0%

3. 9.1%

4. Less than once a month

4. 1.8%

4. 3.4%

5. Only experimented

5. 6.5%

5. 15.4%

6. Never, not even one puff

6. 76.5%

n.a.

Smoking quantity per week

M = 3.63

M = 37.15

SD = 15.10

SD = 45.76

Length of time smoking (years)

M = 3.52

SD = 2.37

With whom do you live?

1. Both parents

1. 84.5%

2. Mother

2. 10.6%

3. Father

3. 1.6%

4. Other

4. 3.2%

Extraversion

1 'not at all' to 7. 'very much'

M = 4.85

SD = .92

Neuroticism

1 'not at all' to 7. 'very much'

M = 3.72

SD = .98

Maternal smoking

1. Smoking mother

1. 40.5%

2. No smoking mother

2. 59.5%

Paternal smoking

1. Smoking father

1. 42.7%

2. No smoking father

2. 57.3%

Number of friends smoking

1. None

1. 45.4%

2. Less than half

3. Half

2. 35.1%

3. 7.8%

4. More than half

4. 9.8%

5. All

5. 1.5%

Behavioural aspects of nicotine dependence

B1: How soon after you wake up do you smoke your first cigarette

1. After 60 minutes

1. 61.1%

2. Within 31-60 minutes

2. 15.8%

3. Within 6-30 minutes

3. 15.7%

4. Within 5 minutes

4. 7.4%

B2: How many cigarettes do you smoke in a day?

1. Fewer than 1 a day

1. 35.3%

2. About 1-5 a day

2. 21.5%

3. About 6-10 a day

3. 22.2%

4. About 11-20 a day

4. 17.3%

5. About 21-30 a day

5. 2.3%

6. More than 30 a day

6. 1.4%

B3: Which cigarette would you hate to give up?

1. Any other cigarette

1. 74.0%

2. First in the morning

2. 26.0%

B4. Do you smoke if you are so ill that you are in bed most of the day?

1. No

1. 84.4%

2. Yes

2. 15.6%

Craving

C1: Have you ever felt like you were addicted to tobacco?

1. Never

1. 33.5%

2. Seldom

2. 17.1%

3. Sometimes

3. 30.8%

4. Often

4. 18.5%

C2: Do you ever have strong cravings to smoke?

1. Never

1. 9.4%

2. Seldom

2. 19.5%

3. Sometimes

3. 45.6%

4. Often

4. 25.4%

C3: Have you ever felt like you really needed a cigarette?

1. Never

1. 24.5%

2. Seldom

2. 20.0%

3. Sometimes

3. 37.5%

4. Often

4. 17.6%

C/W4: Do you smoke because it is really hard to quit?

1. No, not at all

1. 60.7%

2. A little

2. 20.6%

3. Quite

3. 14.5%

4. Yes, very

4. 3.7%

Withdrawal

W1: Trouble concentrating

1. Never

1. 62.9%

2. Seldom

2. 17.8%

3. Sometimes

3. 13.3%

4. Often

4. 5.0%

W2: Feeling irritable or angry

1. Never

1. 58.8%

2. Seldom

2. 16.3%

3. Sometimes

3. 17.8%

4. Often

4. 6.2%

W3: Feeling nervous, restless or anxious

1. Never

1. 69.6%

2. Seldom

2. 17.6%

3. Sometimes

3. 9.1%

4. Often

4. 2.8%