583504 research-article2015
APHXXX10.1177/1010539515583504Asia-Pacific Journal of Public HealthKim et al
Original Manuscript
Reliability and Validity of the Korean Version of the Dimensions of Tobacco Dependence Scale for Adolescents
Asia-Pacific Journal of Public Health 1–9 © 2015 APJPH Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1010539515583504 aph.sagepub.com
Ji Young Kim, RN, PhD, Sung Hee Ko, RN, PhD, Hyun Kyung Kim, RN, PhD, Sung Reul Kim, RN, PhD, and Hye Young Kim, RN, PhD
Abstract This study assessed the reliability and validity of the Korean version of the Dimensions of Tobacco Dependence Scale (DTDS) for adolescents in Korea. The DTDS, Modified Fagerström Tolerance Questionnaire (M-FTQ), and urine nicotine test were administered to 360 Korean adolescents. The collected data were analyzed using SPSS 21.0 and AMOS 21.0. The construct validity, criterion validity, test-retest reliability, internal consistency reliability, and the area under the curve (AUC) of the Korean version of the DTDS were evaluated. The 4-subscale model of the DTDS (with social, emotional, physical, and sensory subscales) was validated using confirmatory factor analysis, and criterion validity was demonstrated with the M-FTQ. Furthermore, the AUC of the DTDS was 83.1. The Cronbach’s α coefficient for internal consistency was .96, demonstrating sufficient test-retest reliability. The Korean version of the DTDS is a reliable and valid measure of tobacco dependence among Korean adolescents. Keywords adolescent, reliability, validity, tobacco dependence, Korean version
Introduction Cigarette smoking among adolescents is a serious problem affecting both individual well-being and public health. The smoking rate among Korean adolescents has been gradually increasing, rising from 14.3% in 2005 to 16.3% in 2012.1 Nicotine dependence is a major impediment when attempting to quit smoking.2 For adolescents in particular, it is the biggest predictor for smoking relapse.3 Accordingly, assessing nicotine dependence among smokers and counseling them on smoking cessation has long been an important challenge to help induce youth to quit.4 Given this, an accurate assessment of nicotine dependence may be an important factor in predicting adolescents’ intentions when they consider smoking cessation.5
Chonbuk National University, Jeollabuk-do, South Korea Corresponding Author: Hye Young Kim, College of Nursing, Chonbuk National University, 567, Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, 561-756, South Korea. Email: [email protected]
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Tools such as the Modified Fagerström Tolerance Questionnaire (M-FTQ) and the Fagerström Test for Nicotine Dependence have been used to assess nicotine dependence.6,7 However, the latter questionnaire consists of questions that reflect physical dependence, such as how long and how much a smoker has been smoking. Because it fails to reflect various aspects of nicotine dependence, the argument was made that a new model that reflects psychological and social dependence is needed.8,9 Nicotine dependence is multidimensional in nature and may be approached from biological, psychological, and sociocultural frameworks.5,9 Physical dependence includes craving, resistance, repeated exposure, and withdrawal symptoms.10 Psychological dependence is related to preference, control, emotional reward, and stress management through smoking.10 Social dependence is derived from elements related to social structure, such as maintaining personal relationships with friends through smoking and self-identification through peer comparisons.10 The social environmental factors related to adolescent smoking are the smoking rates in schools and among peer groups.11 Studies on smoking cessation have shown that even using nicotine replacement therapy and supplemental drug treatments to treat physical dependence resulted in a low success rate.12,13 A recent report, which followed smokers for up to 8 years, found that 46% of those who were successful in quitting smoking reverted to smoking, regardless of treatment.14 This is evidence of the importance of social and psychological dependence, in addition to the physical dependence, in nicotine dependence. The Dimensions of Tobacco Dependence Scale (DTDS) is a multidimensional measure of tobacco dependence that builds on traditional measures of nicotine addiction by incorporating psychosocial determinants of adolescent cigarette smoking.9 That is, it is a useful tool for holistically understanding tobacco dependence among adolescents. Administering this tool to adolescent smokers may provide a comprehensive understanding of their multidimensional tobacco dependence and help in developing effective interventions for smoking cessation. The aims of the current study were to adapt the DTDS for use in South Korea and verify its reliability and validity, which will allow the Korean version of the DTDS to be used to assess tobacco dependence among Korean adolescents.
Methods Participants and Setting The study sample comprised 360 adolescent smokers, recruited between January 2014 and June 2014, from 17 middle schools and 18 high schools in the Jeollabuk-do region of South Korea. Participants completed self-report questionnaires, which took an average of 20 minutes, during class time. The inclusion criteria for this study were as follows: female and male adolescents 13 to 18 years old, who had smoked at least once in the year preceding the survey. Ethical approval was obtained in December 2013 from the institutional review boards (IRBs) at Chonbuk National University (IRB No. 2013-11-012). Participants and their parents provided written consent after being informed about the study’s purpose, procedure, voluntary participation, and guaranteed anonymity, in addition to the ability to leave the study at any time. The sample size required to test the validity of a measurement tool using confirmatory factor analysis (CFA) is at least more than 200 or 5 to 20 times the number of items.15 The questionnaire has 27 items, and the sample of 360 satisfied the sample size requirements.
Measurements The DTDS is a 27-item questionnaire (each using a 4-point Likert scale) of the English questionnaire comprising 6 social dependence questions, 6 emotional dependence questions, 10 physical
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Kim et al
dependence questions, and 5 sensory dependence questions.16 This tool has been developed through the 3-time validation test.9,16,17 Higher scores are associated with a greater number of symptoms. The interim Korean version of the DTDS was formed using the translation and cultural adaptation processes suggested by the World Health Organization.18 The DTDS questionnaire was translated by 2 bilingual and English-speaking university professors, and a back translation was undertaken by a different set of bilingual and English-speaking university professors. In addition, the interim Korean version of the DTDS was pilot tested with 20 adolescent smokers in January 2014. Participants found all the interim Korean version DTDS questions to be acceptable and understandable. For each participant, the Korean version of the DTDS and the M-FTQ7 were administered, in addition to a urine collection test. The amount of nicotine in the urine was analyzed using the NicoFind (Humasis) kit to calculate the area under the curve (AUC) and cutoff point of the Korean DTDS. The NicoFind (Humasis) is a diagnostic kit that can detect cotinine, a metabolite of nicotine, in urine. A positive result indicates the presence of cotinine in urine; a negative result indicates the opposite. A total of 7 items were used to assess gender, age, smoking status, the number of days smoked over the past 30 days, the number of cigarettes smoked per day over the past 30 days, parent smoking, and friend smoking.
Data Analysis Data were managed and analyzed with SPSS version 21.0 and AMOS 21.0. Statistical significance was set at 5%. Descriptive statistics (eg, percentage, mean, standard deviation) were calculated for the general characteristics of participants. The internal consistency reliability of the DTDS was determined using the Cronbach’s α coefficient. For test-retest reliability, a subset of the participants (n = 30) completed the test twice at a 2-week interval. The test-retest reliability of the DTDS was assessed by calculating interclass correlations (ICCs) between the baseline and retest results. Construct validity was confirmed based on the construct reliability of the subscales, the convergent and discriminant validity between the subscales, and a model fit test of the structure using CFA. Criterion validity was determined by calculating Pearson’s correlations between the DTDS and the M-FTQ. The receiver operating characteristics (ROC) curve was used to analyze the results of the urine nicotine test to calculate the AUC and cutoff point for the Korean DTDS.
Results General Characteristics Table 1 summarizes general participant characteristics. The mean age was 15.17 years (standard deviation = 1.28), and 87.2% (n = 314) of participants were male. In addition, 83.0% (n = 299) of the participants were current smokers, and 58.6% (n = 211) of the participants reported smoking every day for the past 30 days. The number of cigarettes smoked per day over the past 30 days was reported by 36.7% (n = 132), with 6 to 10 cigarettes smoked per day. In addition, 61.4% (n = 221) responded that their fathers smoked, and 89.3% (n = 302) reported that they had 5 or more friends who smoked.
Reliability Cronbach’s α coefficients for the social, emotional, physical, and sensory subscales of the DTDS were 0.88, 0.92, 0.91, and 0.86, respectively, which exceeded the 0.70 standard (Table 2).19 Testretest ICCs ranged from 0.90 to 0.91, which also exceeded the 0.80 standard.19 Downloaded from aph.sagepub.com at CMU Libraries - library.cmich.edu on September 21, 2015
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Table 1. General Participant Characteristics (n = 360). Characteristics
Classification
Gender
n (%) or Mean (SD, Range)
Male Female
Age Smoking status
During the past 30 days, smoked day (days)
During the past 30 days, number of cigarettes smoked per day (number)
Parent smoking
Friend smoking (number)
Current Occasional Missing None 1-2 3-5 6-9 10-19 20-29 Every day Missing None 1 2-5 6-10 11-20 More than 21 Missing Father smoking Mother smoking No smoking None 1 2 3 4 More than 5
Total M-FTQ score
314 (87.2) 46 (12.8) 15.17 (1.28, 13-18) 299 (83.1) 53 (14.7) 8 (2.2) 29 (8.1) 25 (6.9) 15 (4.2) 16 (4.4) 28 (7.8) 30 (8.3) 211 (58.6) 6 (1.7) 25 (6.9) 13 (3.6) 81 (22.5) 132 (36.7) 72 (20.0) 33 (9.2) 4 (1.1) 221 (61.4) 45 (12.5) 94 (26.1) 13 (3.6) 13 (3.6) 5 (1.4) 12 (3.3) 15 (4.2) 302 (83.9) 3.77 (1.87, 0-9)
Abbreviations: SD, standard deviation; M-FTQ, Modified Fagerström Tolerance Questionnaire.
Validity The construct validity test was confirmed based on the construct reliability of substructures, convergent validity and discriminant validity between substructures, and a model fit test of the entire structure in item as determined through CFA.20 Items within a single measure should have interitem correlation coefficients of greater than 0.30.21 The intersubscale correlations of the DTDS were moderate or strong, varying between 0.39 and 0.71, which confirmed its construct validity (Table 2). The composite reliability (CR) for all 4 subscales had a standard value of ≥0.70.21 The CR for the emotional subscale was the highest (0.94), and the CR for the sensory subscale was the lowest (0.86). The average variance extracted (AVE) was 0.63, 0.69, 0.56, and 0.50 for the social, emotional, physical, and sensory subscales, respectively. Thus, all the subscales exceeded the recommended value of ≥0.50.21 In addition, the AVEs were larger than the square of the intersubscale correlations (Table 2), which confirmed convergent and discriminant validity.21
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Kim et al Table 2. Construct Validity and Reliability of the DTDS. Constructs Social
Emotional
Physical
Sensory
Items Smoking helps me fit in at school Smoking makes me feel popular Smoking makes me look cool Giving cigarettes to friends makes me feel important Sharing cigarettes helps me feel closer to other people Smoking makes me look more mature Mean (SD, range) I need to smoke when I am stressed I need to smoke when I am depressed I need to smoke to relax I need a cigarette to calm me down when I am angry I need to smoke when I am nervous I need to smoke when I am sad Mean (SD, range) I need to keep my nicotine levels up My smoking is automatic—I don’t even think about it My body needs cigarettes to feel right I can function better after my first cigarette of the day My body craves cigarettes when I don’t smoke I feel panicked when I run out of cigarettes Even when I don’t have time for a whole cigarette, I manage to fit in a few drags I can concentrate better after a cigarette I find myself looking forward to my next cigarette I have strong cravings to smoke cigarettes Mean (SD, range) I like the feeling of blowing out smoke Smoking makes things like having a pop or a coffee more enjoyable I like the taste of cigarettes I enjoy holding and handling cigarettes I enjoy the feeling of smoke in my lungs Mean (SD, range)
Factor Cronbach’s Loading α 0.67 0.89 0.89 0.81
0.88
CR
AVE
Intersubscale Correlation
0.89
0.63
0.39-0.52a
0.62 0.84 0.86 0.83 0.80 0.86
0.92
9.68 (4.13, 6-24) 0.94 0.69 0.39-0.69a
0.82 0.80 16.38 (6.20, 6-24) 0.92 0.56 0.51-0.70a
0.60 0.61
0.65 0.57
0.70
0.91
0.83
0.81
0.80
0.80
0.65
0.83 0.55
0.86
20.43 (7.73, 10-40) 0.86 0.50 0.42-0.71a
0.78 0.69 0.65 10.17 (4.16, 5-20)
Abbreviations: DTDS, Dimensions of Tobacco Dependence Scale; CR, composite reliability; AVE, average variance extract; SD, standard deviation. aP < .001.
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Table 3. Model Fit Test Results. Absolute Fit Indexes 27 Items
Incremental Fit Indexes
χ2 (P)
GFI
AGFI
RMSR
NFI
CFI
937.87 (P < .001)
0.91
0.89
0.04
0.90
0.92
Abbreviations: GFI, goodness of fit index; AGFI, adjusted goodness of fit index; RMSR, root-mean-square residual; NFI, normed fit index; CFI, comparative fit index.
Table 4. Correlations Between the DTDS and M-FTQ for Criterion Validity. Subscales in DTDS M-FTQ
Social r (P)
Emotional r (P)
Physical r (P)
Sensory r (P)
0.23 (
APHXXX10.1177/1010539515583504Asia-Pacific Journal of Public HealthKim et al
Original Manuscript
Reliability and Validity of the Korean Version of the Dimensions of Tobacco Dependence Scale for Adolescents
Asia-Pacific Journal of Public Health 1–9 © 2015 APJPH Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1010539515583504 aph.sagepub.com
Ji Young Kim, RN, PhD, Sung Hee Ko, RN, PhD, Hyun Kyung Kim, RN, PhD, Sung Reul Kim, RN, PhD, and Hye Young Kim, RN, PhD
Abstract This study assessed the reliability and validity of the Korean version of the Dimensions of Tobacco Dependence Scale (DTDS) for adolescents in Korea. The DTDS, Modified Fagerström Tolerance Questionnaire (M-FTQ), and urine nicotine test were administered to 360 Korean adolescents. The collected data were analyzed using SPSS 21.0 and AMOS 21.0. The construct validity, criterion validity, test-retest reliability, internal consistency reliability, and the area under the curve (AUC) of the Korean version of the DTDS were evaluated. The 4-subscale model of the DTDS (with social, emotional, physical, and sensory subscales) was validated using confirmatory factor analysis, and criterion validity was demonstrated with the M-FTQ. Furthermore, the AUC of the DTDS was 83.1. The Cronbach’s α coefficient for internal consistency was .96, demonstrating sufficient test-retest reliability. The Korean version of the DTDS is a reliable and valid measure of tobacco dependence among Korean adolescents. Keywords adolescent, reliability, validity, tobacco dependence, Korean version
Introduction Cigarette smoking among adolescents is a serious problem affecting both individual well-being and public health. The smoking rate among Korean adolescents has been gradually increasing, rising from 14.3% in 2005 to 16.3% in 2012.1 Nicotine dependence is a major impediment when attempting to quit smoking.2 For adolescents in particular, it is the biggest predictor for smoking relapse.3 Accordingly, assessing nicotine dependence among smokers and counseling them on smoking cessation has long been an important challenge to help induce youth to quit.4 Given this, an accurate assessment of nicotine dependence may be an important factor in predicting adolescents’ intentions when they consider smoking cessation.5
Chonbuk National University, Jeollabuk-do, South Korea Corresponding Author: Hye Young Kim, College of Nursing, Chonbuk National University, 567, Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do, 561-756, South Korea. Email: [email protected]
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Asia-Pacific Journal of Public Health
Tools such as the Modified Fagerström Tolerance Questionnaire (M-FTQ) and the Fagerström Test for Nicotine Dependence have been used to assess nicotine dependence.6,7 However, the latter questionnaire consists of questions that reflect physical dependence, such as how long and how much a smoker has been smoking. Because it fails to reflect various aspects of nicotine dependence, the argument was made that a new model that reflects psychological and social dependence is needed.8,9 Nicotine dependence is multidimensional in nature and may be approached from biological, psychological, and sociocultural frameworks.5,9 Physical dependence includes craving, resistance, repeated exposure, and withdrawal symptoms.10 Psychological dependence is related to preference, control, emotional reward, and stress management through smoking.10 Social dependence is derived from elements related to social structure, such as maintaining personal relationships with friends through smoking and self-identification through peer comparisons.10 The social environmental factors related to adolescent smoking are the smoking rates in schools and among peer groups.11 Studies on smoking cessation have shown that even using nicotine replacement therapy and supplemental drug treatments to treat physical dependence resulted in a low success rate.12,13 A recent report, which followed smokers for up to 8 years, found that 46% of those who were successful in quitting smoking reverted to smoking, regardless of treatment.14 This is evidence of the importance of social and psychological dependence, in addition to the physical dependence, in nicotine dependence. The Dimensions of Tobacco Dependence Scale (DTDS) is a multidimensional measure of tobacco dependence that builds on traditional measures of nicotine addiction by incorporating psychosocial determinants of adolescent cigarette smoking.9 That is, it is a useful tool for holistically understanding tobacco dependence among adolescents. Administering this tool to adolescent smokers may provide a comprehensive understanding of their multidimensional tobacco dependence and help in developing effective interventions for smoking cessation. The aims of the current study were to adapt the DTDS for use in South Korea and verify its reliability and validity, which will allow the Korean version of the DTDS to be used to assess tobacco dependence among Korean adolescents.
Methods Participants and Setting The study sample comprised 360 adolescent smokers, recruited between January 2014 and June 2014, from 17 middle schools and 18 high schools in the Jeollabuk-do region of South Korea. Participants completed self-report questionnaires, which took an average of 20 minutes, during class time. The inclusion criteria for this study were as follows: female and male adolescents 13 to 18 years old, who had smoked at least once in the year preceding the survey. Ethical approval was obtained in December 2013 from the institutional review boards (IRBs) at Chonbuk National University (IRB No. 2013-11-012). Participants and their parents provided written consent after being informed about the study’s purpose, procedure, voluntary participation, and guaranteed anonymity, in addition to the ability to leave the study at any time. The sample size required to test the validity of a measurement tool using confirmatory factor analysis (CFA) is at least more than 200 or 5 to 20 times the number of items.15 The questionnaire has 27 items, and the sample of 360 satisfied the sample size requirements.
Measurements The DTDS is a 27-item questionnaire (each using a 4-point Likert scale) of the English questionnaire comprising 6 social dependence questions, 6 emotional dependence questions, 10 physical
Downloaded from aph.sagepub.com at CMU Libraries - library.cmich.edu on September 21, 2015
3
Kim et al
dependence questions, and 5 sensory dependence questions.16 This tool has been developed through the 3-time validation test.9,16,17 Higher scores are associated with a greater number of symptoms. The interim Korean version of the DTDS was formed using the translation and cultural adaptation processes suggested by the World Health Organization.18 The DTDS questionnaire was translated by 2 bilingual and English-speaking university professors, and a back translation was undertaken by a different set of bilingual and English-speaking university professors. In addition, the interim Korean version of the DTDS was pilot tested with 20 adolescent smokers in January 2014. Participants found all the interim Korean version DTDS questions to be acceptable and understandable. For each participant, the Korean version of the DTDS and the M-FTQ7 were administered, in addition to a urine collection test. The amount of nicotine in the urine was analyzed using the NicoFind (Humasis) kit to calculate the area under the curve (AUC) and cutoff point of the Korean DTDS. The NicoFind (Humasis) is a diagnostic kit that can detect cotinine, a metabolite of nicotine, in urine. A positive result indicates the presence of cotinine in urine; a negative result indicates the opposite. A total of 7 items were used to assess gender, age, smoking status, the number of days smoked over the past 30 days, the number of cigarettes smoked per day over the past 30 days, parent smoking, and friend smoking.
Data Analysis Data were managed and analyzed with SPSS version 21.0 and AMOS 21.0. Statistical significance was set at 5%. Descriptive statistics (eg, percentage, mean, standard deviation) were calculated for the general characteristics of participants. The internal consistency reliability of the DTDS was determined using the Cronbach’s α coefficient. For test-retest reliability, a subset of the participants (n = 30) completed the test twice at a 2-week interval. The test-retest reliability of the DTDS was assessed by calculating interclass correlations (ICCs) between the baseline and retest results. Construct validity was confirmed based on the construct reliability of the subscales, the convergent and discriminant validity between the subscales, and a model fit test of the structure using CFA. Criterion validity was determined by calculating Pearson’s correlations between the DTDS and the M-FTQ. The receiver operating characteristics (ROC) curve was used to analyze the results of the urine nicotine test to calculate the AUC and cutoff point for the Korean DTDS.
Results General Characteristics Table 1 summarizes general participant characteristics. The mean age was 15.17 years (standard deviation = 1.28), and 87.2% (n = 314) of participants were male. In addition, 83.0% (n = 299) of the participants were current smokers, and 58.6% (n = 211) of the participants reported smoking every day for the past 30 days. The number of cigarettes smoked per day over the past 30 days was reported by 36.7% (n = 132), with 6 to 10 cigarettes smoked per day. In addition, 61.4% (n = 221) responded that their fathers smoked, and 89.3% (n = 302) reported that they had 5 or more friends who smoked.
Reliability Cronbach’s α coefficients for the social, emotional, physical, and sensory subscales of the DTDS were 0.88, 0.92, 0.91, and 0.86, respectively, which exceeded the 0.70 standard (Table 2).19 Testretest ICCs ranged from 0.90 to 0.91, which also exceeded the 0.80 standard.19 Downloaded from aph.sagepub.com at CMU Libraries - library.cmich.edu on September 21, 2015
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Table 1. General Participant Characteristics (n = 360). Characteristics
Classification
Gender
n (%) or Mean (SD, Range)
Male Female
Age Smoking status
During the past 30 days, smoked day (days)
During the past 30 days, number of cigarettes smoked per day (number)
Parent smoking
Friend smoking (number)
Current Occasional Missing None 1-2 3-5 6-9 10-19 20-29 Every day Missing None 1 2-5 6-10 11-20 More than 21 Missing Father smoking Mother smoking No smoking None 1 2 3 4 More than 5
Total M-FTQ score
314 (87.2) 46 (12.8) 15.17 (1.28, 13-18) 299 (83.1) 53 (14.7) 8 (2.2) 29 (8.1) 25 (6.9) 15 (4.2) 16 (4.4) 28 (7.8) 30 (8.3) 211 (58.6) 6 (1.7) 25 (6.9) 13 (3.6) 81 (22.5) 132 (36.7) 72 (20.0) 33 (9.2) 4 (1.1) 221 (61.4) 45 (12.5) 94 (26.1) 13 (3.6) 13 (3.6) 5 (1.4) 12 (3.3) 15 (4.2) 302 (83.9) 3.77 (1.87, 0-9)
Abbreviations: SD, standard deviation; M-FTQ, Modified Fagerström Tolerance Questionnaire.
Validity The construct validity test was confirmed based on the construct reliability of substructures, convergent validity and discriminant validity between substructures, and a model fit test of the entire structure in item as determined through CFA.20 Items within a single measure should have interitem correlation coefficients of greater than 0.30.21 The intersubscale correlations of the DTDS were moderate or strong, varying between 0.39 and 0.71, which confirmed its construct validity (Table 2). The composite reliability (CR) for all 4 subscales had a standard value of ≥0.70.21 The CR for the emotional subscale was the highest (0.94), and the CR for the sensory subscale was the lowest (0.86). The average variance extracted (AVE) was 0.63, 0.69, 0.56, and 0.50 for the social, emotional, physical, and sensory subscales, respectively. Thus, all the subscales exceeded the recommended value of ≥0.50.21 In addition, the AVEs were larger than the square of the intersubscale correlations (Table 2), which confirmed convergent and discriminant validity.21
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Kim et al Table 2. Construct Validity and Reliability of the DTDS. Constructs Social
Emotional
Physical
Sensory
Items Smoking helps me fit in at school Smoking makes me feel popular Smoking makes me look cool Giving cigarettes to friends makes me feel important Sharing cigarettes helps me feel closer to other people Smoking makes me look more mature Mean (SD, range) I need to smoke when I am stressed I need to smoke when I am depressed I need to smoke to relax I need a cigarette to calm me down when I am angry I need to smoke when I am nervous I need to smoke when I am sad Mean (SD, range) I need to keep my nicotine levels up My smoking is automatic—I don’t even think about it My body needs cigarettes to feel right I can function better after my first cigarette of the day My body craves cigarettes when I don’t smoke I feel panicked when I run out of cigarettes Even when I don’t have time for a whole cigarette, I manage to fit in a few drags I can concentrate better after a cigarette I find myself looking forward to my next cigarette I have strong cravings to smoke cigarettes Mean (SD, range) I like the feeling of blowing out smoke Smoking makes things like having a pop or a coffee more enjoyable I like the taste of cigarettes I enjoy holding and handling cigarettes I enjoy the feeling of smoke in my lungs Mean (SD, range)
Factor Cronbach’s Loading α 0.67 0.89 0.89 0.81
0.88
CR
AVE
Intersubscale Correlation
0.89
0.63
0.39-0.52a
0.62 0.84 0.86 0.83 0.80 0.86
0.92
9.68 (4.13, 6-24) 0.94 0.69 0.39-0.69a
0.82 0.80 16.38 (6.20, 6-24) 0.92 0.56 0.51-0.70a
0.60 0.61
0.65 0.57
0.70
0.91
0.83
0.81
0.80
0.80
0.65
0.83 0.55
0.86
20.43 (7.73, 10-40) 0.86 0.50 0.42-0.71a
0.78 0.69 0.65 10.17 (4.16, 5-20)
Abbreviations: DTDS, Dimensions of Tobacco Dependence Scale; CR, composite reliability; AVE, average variance extract; SD, standard deviation. aP < .001.
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Table 3. Model Fit Test Results. Absolute Fit Indexes 27 Items
Incremental Fit Indexes
χ2 (P)
GFI
AGFI
RMSR
NFI
CFI
937.87 (P < .001)
0.91
0.89
0.04
0.90
0.92
Abbreviations: GFI, goodness of fit index; AGFI, adjusted goodness of fit index; RMSR, root-mean-square residual; NFI, normed fit index; CFI, comparative fit index.
Table 4. Correlations Between the DTDS and M-FTQ for Criterion Validity. Subscales in DTDS M-FTQ
Social r (P)
Emotional r (P)
Physical r (P)
Sensory r (P)
0.23 (
