Characteristics
Category
Case (n)
(%)
Age (year)
14-17
152
76.0

18-20

48

24.0

Mean±SD

16.49±1.13

Gender

Girl

24

12.0

Male

176

88.0
Second-hand smoking

Mother

72

36.0

Father

111

55.5

Sister/brother

45

22.5

Friends

178

89.0
*Reason for smoking

Peer pressure

123

61.5

Stress

92

46.0

Wonder

42

21.0

Emulation

14

7.0
Nicotine Dependency Level (n=192)

Very low

88

44.0

Low

44

22.0

Moderate

25

12.5

High

24

12.0

Very high

11

5.5

*More than one option is possible.
n= number of participation, %=percent
SD=standard deviation
Table 1: Main characteristics at baseline (n=200)
Stage of change at baseline Pre-test Post-test Statistic
 

n

%

n

%

x2

p

Precontemplation stage

85

42.5

25

12.5

38.65

.00

Contemplation stage

65

32.5

53

26.5

3.90

.04

Preparation stage

50

25

69

34.5

11.21

.00

Action stage

-

-

53

26.5

 

 

x2= chi-square test, n= number of participation
p=statistical significant level
Table 2: The change stages of the students concerning smoking cessation before and after the motivational interviews
TTM constructs

Pre-test

Post-test

Statistics

Mean±SD

Mean±SD

Z

p
 FTQ
3.31±2.55
2.35±2.27
4.89
.00
DBS

Social Pros

4.95±2.53

4.87±2.58

1.91

.05

Coping Pros

8.25±3.22

7.72±3.50

0.47

.63

Cons

18.44±7.85

26.76±5.13

2.46

0.01
SES

Negative Affect

5.67±2.58

5.72±2.41

0.70

.47

Positive Social Environments

5.89±2.26

5.74±2.23

086

.89

Habit Strength

5.94±2.40

5.90±2.58

0.10

.92

Weight Control

5.98±3.33

6.17±3.31

0.76

.44

Combined

23.53±7.41

23.55±8.13

0.80

.42

Z= Wilcoxon’s test, p=statistical significant level, SD=standard deviation
TTM=Transtheoretical Model
FTQ=Fagerström Tolerance Questionnaire, DBS=Decisional Balance, SES=Self Efficiency Scale
Table 3: The comparison of the total scores of the students in FTQ, DBS and SES before and after MI

    Stages of change Statistics Post hoc test
TTM Constructs  

PC (n=25)
mean±SD

C (n=53) mean±SD

PR (n=69) mean±SD

A (n=53) mean±SD

x2

Z

FTQ

 

4.84±2.49

2.32±1.89

2.85±2.03

0.58±1.21

67.30***

A<PC, C, PR

DBS

Social Pros

5.33±2.61

4.94±2.62

4.88±2.47

4.59±2.32

1.46

 

Coping Pros

9.00±3.50

8.27±3.19

8.11±3.61

6.03±3.12

17.53***

A<PC, P, PR

Cons

22.62±7.41

25.17±5.42

26.42±4.68

26.28±5.61

7.29

 
SES

Negative Affect

6.40±2.58

6.35±2.14

6.01±2.22

6.35±2.95

1.16

 

Positive Social Environment

6.44±1.75

5.90±1.93

6.33±2.09

6.28±2.96

1.73

 

Habit Strength

5.04±2.82

4.35±2.63

5.47±2.85

6.16±3.45

9.11**

A>PR, PC, C

Weight Control

2.36±3.20

4.05±3.97

5.40±4.15

5.41±4.21

13.41***

A>PR, C, PC

Combined

23.64±6.75

24.96±6.70

24.96±6.70

22.32±0.63

2.58

 

PC=Precontemplation, C=Contemplation, PR=Preparation, A=Action
TTM= Transtheoretical Model
FTQ= Fagerström Tolerance Questionnaire, DBS=Decisional Balance, SES=Self Efficiency Scale
x2 = Kruskall Wallis test **p < 0.01, ***0.001 Mean differences for the Bonferroni corrected Mann-Whitney U tests pair wise comparisons (p<0.012).
Z= Man Whitney U test
Table 4: The comparison of the post-test scores of the TTM constructs according to stages of change