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Introduction (Shiffman et al ., 2003). Also, long- Measures of cigarette-induced term use of nicotine medications nicotine dependence In this section, evidence of the has no documented untoward validity of self-report measures of health effects, so therefore mea- The following section provides a nicotine/ dependence in surement of dependence to nicotine brief review of data on the adults is examined. Measures are medications will not be included in measurement properties of seven concentrated on that are potentially this review. Finally, while depen- self-report measures developed to appropriate for population-based/ dence on tobacco products is assess the construct of cigarette- epidemiologic research, as nicotine clearly evident among some youth, induced nicotine dependence: 1) dependence is often assessed as a research on measures of nicotine Fagerström Test for Nicotine potential moderator of programme dependence in adolescents is Dependence (FTND); 2) Heaviness and policy effects. The Working limited, and will not be considered in of Smoking Index (HSI); 3) Diag- Group (WG) has focused mainly on this section. For those interested in nostic and Statistical Manual-IV scales measuring cigarette depen- a measure of nicotine dependence (DSM-IV) criterion of dependence; dence, as cigarette smoking among youth, please refer to the 4) International Statistical Classi- accounts for most of the health paper which describes the mea- fication and Related Health Prob- damage caused by tobacco, and surement properties of the Hooked lems-10 (ICD-10) criteria; 5) Ci- because the most widely used and on Nicotine Checklist (DiFranza et garette Dependence Scale (CDS); best studied scales measure al ., 2002b). 6) Nicotine Dependence Syndrome cigarette dependence. This section Nicotine dependence is a hypo- Scale (NDSS); and 7) Wisconsin has not attempted to review evi- thetical construct that is designed to Inventory of Smoking Dependence dence evaluating measures to explain and predict societally- Motives (WISDM). assess nicotine dependence of important outcomes, such as an Each measure will be evaluated other types of smoked tobacco inability to quit smoking, heavy use, based on a review of the items that products (e.g. cigars, pipe tobacco, and other problems occasioned by constitute the scales in terms of bidis, ), although adaptations smoking or tobacco use (Piper et al. , their reading level, face validity, of measures used to assess 2006). Assessing tobacco depen- coverage of the dependence do- cigarette smoking dependence dence is difficult and is made even main, and cross-cultural applica- would be reasonable to consider. more so in population-based epi- bility. The WG will review the The WG did include a review of demiologic research by the need for psychometrics of each scale, measures of dependence on efficient assessment (valid and brief). including its reliability (e.g. internal smokeless tobacco products, since Ideally, a measure should reflect the consistency) and factor structure, the pattern of compulsive use of nature or domain of the construct of and will examine the predictive these products is similar to that interest (i.e. tobacco dependence), validity of each measure, focusing observed for cigarette smoking predict important outcomes (e.g. on two specific tobacco depen- (IARC, 2007b). Persistent use of likelihood of quitting, problems en- dence criteria: a pattern of nicotine medications has been countered through use), and be pervasive and heavy smoking and described, but it is very rare relatively brief to assess. the ability to quit smoking.

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Pervasive and heavy smoking use. Obviously, a pattern of of cigarettes smoked per day) can could be assessed using self- heavy, pervasive smoking will predict outcomes, such as re- report measures (e.g. cigarettes capture the degree of exposure to lapse, as well as longer measures smoked per day or lifetime nicotine and the harmful (e.g. DSM-III-R, FTQ, and FTND) cigarettes smoked), or using bio- constituents of tobacco/ciga- (Razavi et al., 1999; Breslau & markers of exposure (e.g. carbon rettes. Moreover, a relative Johnson, 2000; Dale, et al. , 2001). monoxide (CO), cotinine, puff inability to quit smoking will When considering the infor- topography) (see Section 3.1), and forecast the likely continued mation comprised here, it is the ability to quit smoking could be exposure to such elements. important to remember that assessed using a number of Evidence shows that past, current, reliability and validity are not strategies as well (see Section and future use of tobacco directly inherent in measures. It can not be 3.1). These criteria reflect the predict outcomes of societal assumed that one can generalize sheer volume of tobacco products import, such as money expended psychometric properties across consumed and the intransigence of in buying tobacco products and different use contexts, or that drug use, both of which have disease outcomes (and asso- validity for one use of a measure significant effects on the health and ciated costs) caused by tobacco is generalizeable for a different economics of both the individual use (US Department of Health and use (e.g. predicting relapse and society. Although it is not a Human Services, 2004; Centers likelihood versus withdrawal validation criterion, the evidence of for Disease Control and Pre- severity). Rather, these features genetic linkages to the various vention, 2005). are estimated based on patterns measures of tobacco dependence of statistical covariation and are will be examined. This information Overarching issues: influenced by the nature of the may be helpful for researchers who population being assessed are interested in using epide- It is important to note that de- (Nunnally & Bernstein, 1994; miological measures to make pendence is a construct (i.e. a McDonald, 1999). For instance, inferences regarding etiology. hypothetical entity). It is not, in there may be less variance in item It is important to note that other theory, equivalent to any single scores, or item scores might have criteria could be used to evaluate measure or criterion (Piper et al., a less skewed distribution, when a the performance of dependence 2006); although single items can dependence measure is used in a measures. For instance, such be used to estimate a person’s clinical population rather than a measures could be evaluated with standing on the construct. Thus, nationally representative popu- respect to prediction of withdrawal dependence is an inferred in- lation. This could easily affect both severity or other outcomes fluence or force that produces the reliability and validity estimates. theoretically linked to dependence outcomes associated with it (e.g. Different populations might yield (Piper et al. , 2006). However, high rates of smoking, relapse), different psychometric data be- such outcomes seem less although it is not the only predictor cause of true differences in the relevant than the ones selected for of such outcomes. Generally it severity or range of dependence. measures to be used in epi- takes multiple variables or items to However, differences might also demiologic research. For the adequately assess a complex, arise because of other factors, purposes of epidemiologic re- hypothetical entity such as such as secular or environmental search, a measure should reflect nicotine dependence (Clark & events that might affect scores on or predict outcomes of societal Watson, 1995). In this section, dependence measures, while not import, such as degree of tobacco however, considerable attention is actually changing the dependence exposure and use, the intran- devoted to very brief measures of per se. One study showed that US sigence of use, and the likelihood dependence, as evidence shows smokers had higher frequencies of important negative outcomes of that such measures (i.e. number of severe nicotine dependence

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(FTND ≥ 6) than did Spanish response burden. In fact, as multidimensional measures tend smokers (de Leon et al ., 2002). It efficient as some of the uni- to ask about relatively discrete is possible that such population dimensional measures are, some processes (e.g. a taste motive for differences reflect different de- data suggest that particular items smoking) rather than global grees or sources of error across from these measures possess consequences of smoking (e.g. the two populations (restrictions in predictive validities that meet or smoking causing problems in life), smoking in the home, the amount exceed those of the whole these multidimensional measures of discretionary income, gender measure (Storr et al., 2005). Such may be more suitable for genetics differences in smoking across the items might be especially valuable research, as they may tap pro- populations, the ways the smo- for epidemiologic research. cesses that reflect a stronger kers answer the questions and, A review of multidimensional genetic signal (Baker et al ., in indeed, understand them and so measures of nicotine dependence press). Finally, because multi- on) rather than differences in the are included despite their length dimensional measures tend to ask biological/psychological internal and reduced efficiency, because about internal and subjective processes that make up depen- they have the potential to provide phenomena (e.g. role of affect dence. There are numerous information about the mechanism regulation) rather than externally environmental or social sources of underlying nicotine dependence referenced events (e.g. latency to error variance that could dif- not supplied by unidimensional smoke in the morning, number of ferentially affect the validity of a measures. For instance, multi- cigarettes consumed each day), measure across populations: smo- dimensional measures are in- these measures may be less king policies in the workplace, tended to assess particular facets susceptible to biasing by error due taxes, religious or social norms, to of dependence or dependence to regional secular or policy list few. processes (e.g. particular motives influences. Workplace smoking In recognition of the depen- for drug use). Thus, these restrictions, for example, might dence of psychometric properties measures may provide greater exert a more direct and larger on the population being assessed, insights into the nature of tobacco effect on number of cigarettes reliability and validity data from dependence than do unidimen- smoked per day than on the both clinical trials and epi- sional measures. They also may smokers liking of the taste of demiologic studies conducted provide greater discrimination cigarettes. On the other hand, around the world, and present amongst smokers/tobacco users multidimensional scales tend to data relating to the heritability of to the extent that smokers may be ask about relatively subtle, psy- dependence as it is assessed distinguished on the basis of chological variables (e.g. asking using the different measures, will something other than a single individuals to attribute smoking be presented. The tobacco intensity dimension (which might urges or affect), and it is possible, dependence measures will be be well captured by a single indeed probable, that cultures divided into two groups: uni- severity dimension). For instance, may differ in how they make dimensional and multidimen- some scales appear to reflect attributions or label internal phe- sional . Unidimensional measures motives associated with initial nomena. Of course, while entire are intended to assess depen- versus extensive use of tobacco multidimensional scales can be dence as a single dimension (Piper et al ., 2004), and other quite lengthy, individual items or (although some, it turns out, may scales differ in sensitivity to use subscales can be selected for use actually be multifactorial). Such patterns of highly dependent (Lerman et al ., 2006); thus, this measures are useful, because the users versus “chippers” (those section will review relevant best of them are fairly efficient in who engage in periodic or light subscale data. that they possess significant tobacco use) (Shiffman & Sayette, The foregoing discussion validity given their length/ 2005). Since the subscales of should make clear that blanket

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recommendations cannot be John et al. , 2004a), Switzerland 0.70 (Etter et al , 1999), while a given regarding dependence. Ra- (Etter et al., 1999), Australia study with a German population ther, the investigator must both (Pergadia et al ., 2006a), Canada found low internal consistency for weigh practical issues (e.g. (Howard et al. , 2003), Austria the FTND ( α =.57 ) in two separate response burden) and clearly (Lesch et al., 2004), and Brazil, samples (John et al ., 2004b), and identify the goals of assessment Mexico, Poland, and China a study in China found that FTQ (e.g. predict probability of relapse) (Blackford et al. , 2006; Huang et had low internal consistency as in order to select an appropriate al. , 2006). The HSI has also been well ( α =.58 ) (Huang et al. , 2006). dependence instrument or as- used in research in Spain (Diaz et Some studies have shown that sessment strategy. al ., 2005), Australia, Canada, UK, the FTND has a two-factor and the USA (Heatherton et al. , structure, suggesting that it does Unidimensional measures of 1991; Hymowitz et al. , 1997; not measure a unitary construct of tobacco dependence Hyland et al. , 2006). One of the (Payne et questions on the FTND concerns al. , 1994; Etter et al ., 1999; Fagerström Test for Nicotine smoking in forbidden places. The Haddock et al. , 1999; Radzius et Dependence and the Heaviness of validity of this question may be al., 2003; Breteler et al ., 2004; Smoking Index affected by regional differences in John et al ., 2004b). A population- environmental restrictions in based study in France found that The first unidimensional measure of smoking (Huang et al ., 2006). In while a two-factor model fit the tobacco dependence is actually a addition, two questions in this data well, the two factors were group of measures arising from the scale assume a pattern of daily highly correlated (Chabrol et al. , Fagerström Tolerance Question- smoking (e.g. questions 1 & 4, the 2003). Inter-item correlations also naire (FTQ) (Fagerström, 1978): two questions in the HSI). It is very reveal that not all items are highly these comprise the FTQ itself, as likely that scores on these items related (r = 0.06-0.39) (Trans- well as the 6-item Fagerström Test will have reduced validity if used disciplinary Tobacco Use Re- for Nicotine Dependence (FTND) with non-daily smokers. An search Center (TTURC) Tobacco (Heatherton et al ., 1991) and the 2- important goal of future research Dependence Phenotype Work- item Heaviness of Smoking Index is to identify dependence mea- group, 2007). These studies (HSI) (Kozlowski et al. , 1994). See sures that are appropriate for suggest that the two factors reflect Appendix 1 for the items and non-daily smokers. morning smoking (i.e. whether scoring. These measures are one smokes more in the morning based on the construct of physical Reliability and structure : Com- and whether one would rather give dependence, which includes facets pared with the FTQ, the FTND has up the first cigarette of the day or such as the need to smoke early in demonstrated better psychometric all others), and smoking pattern the morning to alleviate overnight properties, such as internal con- (i.e. the number of cigarettes withdrawal, the need to smoke sistency (Payne et al., 1994; smoked per day, time to first numerous cigarettes per day, and Pomerleau et al. , 1994; Haddock cigarette, difficulty refraining from the invariance of smoking beha- et al ., 1999); however, these smoking, and smoking when ill), viour (i.e. smoking even when you improved reliability coefficients are although some data indicate that are ill) (Fagerström, 1978). The still low (Etter, 2005) and below time to first cigarette loaded on Flesch-Kincaid Reading Grade traditionally accepted standards both factors (Radzius et al ., 2003). Level is 4.4 for the FTND and 4.2 for clinical use ( α =0.80 ) (Nunnally Latent class analyses suggest that for the HSI. & Bernstein, 1994). Using a the FTND divides smokers into The FTND has been translated French translation of the FTND groups based on severity of and used with population samples with light smokers found internal dependence (Storr et al. , 2005); in Germany (John et al. , 2003a; consistencies of approximately that is the two factors do not

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appear to “pick-out” smokers who heightened risk for psychiatric morning) predicts relapse vul- differ in terms of types of de- comorbidities in a large population nerability, as well as, or better pendence. sample in Germany (John et al. , than, much longer multidimen- The HSI is comprised of only 2005). sional instruments (TTURC two items, which limits the Some data indicate that the Tobacco Dependence Phenotype relevance of internal consistency standard scoring method used Workgroup, 2007). Recent popu- estimates. However, zero-order with the FTND (adding up item lation-based research shows that correlations between the two responses) may not produce an a single item on the HSI (item #1) items in the measure indicate optimal scaling of dependence is highly effective in predicting the moderate levels of association level. Latent class analysis likelihood of future cessation (e.g. r’s ≈ 0.30) (TTURC Tobacco suggested that some items are (TTURC Tobacco Dependence Dependence Phenotype Work- particularly important to the Phenotype Workgroup, 2007). group, 2007). assessment of dependence level (those that capture variance due Heritability : In a study of young Validation : The FTND and HSI to morning smoking) and that they adult Australian Twins, HSI- predict both behavioural and are relatively underweighted in the assessed dependence was found biochemical indices of smoking in typical scoring method (Storr et to be highly heritable (71%) Chinese-, English-, French-, and al. , 2005). Therefore, investigators (Lessov et al. , 2004). In addition, German-speaking populations using the FTND may wish to the FTND and HSI were both (e.g. CO, cotinine, lifetime amount explore alternative, empirically- related to the dopa decarboxylase smoked) (Heatherton et al. , 1989, based scoring or cut-score gene, which is involved in the 1991; Kozlowski et al. , 1994; Etter determination methods (e.g. la- synthesis of , nore- et al ., 1999; John et al. , 2003a; tent class analysis, Receiver pinephrine, and (Ma et Huang et al. , 2006). This should Operating Characteristic curves al ., 2005). One haplotype was not be surprising, given that the (Swets et al. , 2000)). significantly related to depen- FTND and HSI directly assess While the FTND certainly can dence in both African-American smoking heaviness. However, it is predict future smoking or likeli- and Euro-American smokers, encouraging to note that smokers hood of cessation, the HSI while another was related to are indeed able to estimate their appears to account for much of dependence only in Euro-Ameri- amount of smoking as indexed by the predictive validity of that can smokers (Ma et al. , 2005). biochemical tests in response to measure (Breslau & Johnson, Additional studies link FTND- single items (e.g. Question #4 on 2000; Heatherton et al. , 1989; defined dependence to particular the FTND, “How many ciga- TTURC Tobacco Dependence genetic variants (Bierut et al. , rettes/day do you smoke?”). The Phenotype Workgroup, 2007). 2007; Gelernter et al ., 2007; FTND has demonstrated an ability Population-based studies con- Saccone et al. , 2007). to predict cessation outcomes in ducted in Australia, Canada, the studies (Camp- UK, and the USA found that the Summary : The FTND has been bell et al., 1996; Westman et al., two HSI items (number of widely used in a number of 1997; Alterman et al., 1999; cigarettes smoked and time to first different countries and a number Patten et al. , 2001; TTURC cigarette in the morning) were the of different languages. It is short Tobacco Dependence Phenotype strongest predictors of quitting and has an accessible reading Workgroup, 2007), and with col- (Hymowitz et al. , 1997; Hyland et level. In addition, while there are lege students in a popu- al. , 2006). Furthermore, recent concerns regarding its structure lation-based study (Sledjeski et research has shown that a single and reliability, it has been found to al ., 2007). In addition, the FTND item on the FTND and HSI (Item predict smoking heaviness and has been shown to index a #1 – latency to first cigarette in the cessation outcome. However, it

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appears that the HSI is a more ICD-10, DSM-III-R (the 1987 cluding Arabic, Chinese, English, efficient predictor of outcome than revision of DSM-II), and DSM-IV French, Russian, and Spanish. is the FTND (using only two items). symptoms of dependence with a The DIS, CIDI, and other diag- FTND and HSI scores have also Flesch-Kincaid Reading Grade nostic interviews comprise a been found to be heritable and Level of 8.1 (see Appendix 4 for series of branching questions that related to specific dependence- items and scoring). To the best of are aimed at eliciting information linked genetic variants. our knowledge, this is the only about features relevant to nicotine published, self-report DSM/ICD dependence. The Diagnostic and Statistical Man - questionnaire of tobacco/nicotine Some aspects of the DSM- ual, International Statistical Classi- dependence. Most of the existing derived interviews and similar fication of Diseases and Related research has utilised the DSM instruments may cause problems Health Problems, 10th Revision and criteria, and that will be the focus in any sample, or when using the the Tobacco Dependence Screener of this Handbook’s review of instrument with culturally diverse diagnostic classifications of tobac- populations. Another important Two different diagnostic systems co dependence. caveat to observe, in regards to are commonly used to diagnose DSM and ICD structured the DSM measure of dependence, tobacco dependence: both are clinical interviews, such as the is that the scoring algorithm used typically considered to be uni- World Mental Health Survey in establishing formal DSM dimensional measures of tobacco Initiative version of the Composite diagnoses does not appear to dependence. One is the Diag- International Diagnostic Interview yield decision rules that agree with nostic and Statistical Manual of (CIDI), or the National Institute of empirical methods, such as latent Mental Disorders, 4th Edition Mental Health Diagnostic Inter- class analysis (Muthen & (DSM-IV) (American Psychiatric view Schedule (DIS), have been Asparouhov, 2006). Thus, the Association, 1995) 1 which is translated into various languages investigator may wish to explore based on an empirically driven, and used in at least 11 population- different methods for item- syndromal medical model, rather based studies (Hughes et al. , weighting and cut-score estimation than on a theoretical model of 2006) in countries including: if a categorical outcome is dependence (see Appendix 2 for Germany (John et al., 2003b desired. In addition, it should be the criteria). The second is the (DSM); John et al ., 2004a (DSM); noted that the tobacco sections of International Statistical Classi- Hoch et al. , 2004 (DSM)), DIS and CIDI are quite long (over fication of Diseases and Related Australia (Pergadia et al ., 2006b 30 items), and were designed to Health Problems, 10th Revision (DSM)), Canada and Taipei be administered either in a face- (ICD-10), an international diag- (Howard et al. , 2003 (DSM)), to-face interview or by a trained nostic classification system that Spain (de Leon et al. , 2002 professional. New technology has was endorsed by the 43rd World (DSM)), Austria (Lesch et al., made it possible to have indivi- Health Assembly in May 1990 and 2004 (DSM & ICD)), Switzerland duals respond to text-based came into use by WHO Member (Angst et al. , 2005 (DSM)), Japan presentations of the questions, but States as of 1994 (see Appendix (Yoshimura, 2000 (ICD)), Korea it is unknown how valid this 3 for the criteria (WHO, 1993)). (Lee et al. , 1990 (DSM)), and the presentation method would be The Tobacco Dependence USA (Breslau et al. , 2004 (DSM); and it would remain quite time Screener (TDS) (Kawakami et al. , Hughes et al. , 2004a (DSM & consuming. 1999) is a 10-item, self-report ICD)). The ICD-10 criteria are questionnaire designed to assess available in 42 languages, in-

1There has been a text revision of the DSM-IV (American Psychiatric Association, 2000), however this revision did not alter any diagnostic criteria for any diagnostic categories, including the diagnosis

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Reliability and structure : Data on 2004). Investigators might wish to DSM-IV nicotine dependence the reliability and structure of analyze these item parcels diagnosis is associated with diagnostic interview measures of separately since they may be greater risk of psychiatric comor- nicotine dependence arise from addressing somewhat distinct bidities in adults and youth (Grant studies using face-to-face admi- constructs. et al ., 2004; John et al., 2004a; nistration strategies. Therefore, The TDS, a written ques- Dierker et al. , 2006). In addition, the following conclusions cannot tionnaire assessing the presence DSM diagnoses of nicotine be generalized to a different of diagnostic criteria, has demon- dependence were significantly administration format. There is strated acceptable internal associated with self-rated general evidence that the various consistency in Japanese smokers health in a population sample in structured diagnostic measures (α = 0.74-0.81 ) (Kawakami et al ., Germany (John et al. , 2005). In yield reliable diagnoses as 1999), but was less internally sum, there is substantial evidence assessed by test-retest reliability consistent among smokers in the that DSM/ICD diagnoses are (ĸ = 0.63, Grant et al. , 2004; ĸ = USA ( α = 0.64 ) (Piper et al ., 2008). meaningfully related to smoking 0.88, Hughes et al. , 2004a; ĸ = To date, there have been no heaviness and a variety of health 0.73, Koenen et al. , 2005). One- studies comparing the reliability of outcomes. factor analysis indicated that the interview measures with the Studies have shown that the responses to the CIDI had a paper-pencil measure. Therefore, TDS is associated with the strong single factor structure one cannot assume that the smoking heaviness measures (Strong et al ., 2003); although psychometric data generated by (e.g. number of cigarettes smoked other factor analyses of the the interview-format delivery of per day, CO levels) and years of structured diagnostic items found DSM or ICD items would smoking (Kawakami et al. , 1999; that a two-factor structure was a generalize to a self-administered Piper et al. , 2004). With respect to better fit (Johnson et al. , 1996; format. relapse, one study found that Radzius et al ., 2004; Muthen & Japanese smokers with lower Asparouhov, 2006). Patterns of Validation : Evidence suggests that TDS scores were more likely to covariation that were found the small set of dichotomous DSM quit smoking after a health risk amongst the symptoms could be items can distinguish between appraisal (Kawakami et al ., 1999). best accounted for by two factors light versus heavy smoking However, data from smokers who (Muthen et al. , 2006). The first (Strong et al. , 2003). An epi- participated in smoking cessation accounted for covariance in the demiological study found that the studies in the USA, revealed that “tolerance,” “larger amounts,” and DSM-III-R (as assessed by the the TDS did not predict abstinence “time spent using” items (see DIS), was a significant, though at 1-week or 6-months post-quit Appendix 2). Thus, this factor weak, predictor of cigarette (TTURC Tobacco Dependence seems to be highly related to abstinence over one year, but that Phenotype Workgroup, 2007). sheer amount smoked. The se- the FTND was a better predictor cond factor was related to and that number of cigarettes Heritability : There has been “persistent desired/unsuccessful smoked per day was the best considerable research supporting efforts to cut down or quit,” and predictor (Breslau & Johnson, the heritability of DSM/ICD- “continued use despite emotional/- 2000). Another study showed that diagnosed nicotine dependence. physical problems.” Confidence in DSM-IV diagnoses of nicotine In the Australian Twin sample this solution is bolstered by the dependence predicted heaviness study, analyses revealed that all of fact that it was obtained in three of use and cessation outcome in a the DSM-IV symptoms and diag- separate groups of individuals. It population-based study of college nosed DSM-IV dependence were is also consistent with other recent students (Sledjeski et al ., 2007). meaningfully heritable (45-73%), factor analyses (Lessov et al. , Several studies have shown that and that the DSM-IV criteria of

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tolerance, withdrawal, and dif- outcomes as well as the and ≥ 0.83 for the full scales. ficulty quitting were the most diagnostic measures (e.g. John et Factor analysis suggested a highly heritable symptoms of al. , 2004a). In terms of the unidimensional structure for the nicotine dependence for both men prediction of likelihood of future CDS-12. and women (Lessov et al ., 2004). cessation, it is unclear that diag- A study of twin fathers, using the nostic measures possess any Validation: The CDS scales were Vietnam Era Twin Registry, found incremental validity relative to significantly correlated with that paternal DSM diagnosis of briefer measures, such as the number of cigarettes smoked per nicotine dependence was sig- HSI. The diagnostic scales have day (whether a smoker was a nificantly associated with offspring relatively high reading levels, daily or occasional smoker), DSM diagnosis of nicotine which may hinder their use with strength of urges during the last dependence (Volk et al., 2007). certain populations (even if quit attempt, and cotinine level However, one study found that administered orally). (Etter et al. , 2003b). Curiously, the DSM nicotine dependence was CDS-5 was more strongly not related to familial liability to Cigarette Dependence Scale correlated with cotinine levels than smoking persistence, because was the CDS-12. This was familial density of persistence was Th e Cigarette Dependence Scale probably due to the fact that the not associated with smoking (CDS) is another unidimensional question about smoking heavi- persistence among nicotine- tobacco dependence measure ness (Question #2) determined a dependent daily smokers (John- (Etter et al. , 2003b). This assay greater portion of total scale son et al. , 2002). Other genetics was developed using smokers’ variance in the 5-item version. In research has linked DSM- reports of signs that they believed one study, none of the three diagnosed nicotine dependence indicated to cigarettes. dependence measures (i.e. the with the CYP2E1 genotype, which Both a 5- and 12-item version of FTND, CDS-5, or CDS-12) was a codes for a protein that meta- the CDS were developed (see significant predictor of relapse bolizes and tobacco Appendix 5). The items overlap likelihood (Etter et al ., 2003b); smoke nitrosamines, and is somewhat with the Fagerström however, only a third of potential implicated in creating metabolic tests (e.g. they both assess respondents participated in the cross-tolerance between alcohol number of cigarettes smoked per follow-up study, which might have and tobacco (Howard et al., 2003). day and time to first cigarette in the produced considerable response morning). The Flesch-Kincaid bias. In a second study, the CDS- Summary : There is evidence that Reading Grade Levels were 4.9 for 12 weakly predicted smoking diagnostic measures effectively the CDS-12 and 6.8 for the CDS-5. abstinence at 1-month post-quit, index smoking heaviness, smo- but in a counterintuitive direction king-related health and mental Reliability and structure : To date, (e.g. higher CDS-12 scores health risks, and likelihood of only two published studies have predicted abstinence) (Etter, future cessation. There is also reported data on the two versions 2005). strong evidence of heritability of of the CDS, using data collected DSM-diagnosed nicotine depen- via the mail or Internet (Etter et al., Heritability: To date, no data dence. It is unclear whether 2003b; Etter, 2005). The CDS-12 regarding heritability or genetics paper-pencil versions of such had strong internal consistency, have been published using the measures (the TDS) are com- the CDS-5 was within the CDS. parable to the interview versions acceptable range, and both scales of such measures. Moreover, were slightly skewed toward Summary : While the CDS scales there is evidence that the FTND higher values. Test-retest cor- do index smoking heaviness well, may predict cessation and health relations were ≥ 0.60 for all items there is little evidence that they

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predict likelihood of cessation 6). The Flesch-Kincaid Reading item scale. The internal con- effectively, or that they index other Grade Level is 7.7. This reading sistency for the NDSS total scale, health outcomes of level is somewhat elevated relative the NDSS-T, is good (Shiffman et importance. Further, there is little to other self-administered scales, al. , 2004); however, data show evidence that they possess which may reflect the fact that that the internal consistencies of incremental validity relative to some items contain unusual words individual subscales are prob- other measures, such as the and require integration of more lematic (Piper et al ., 2006). Prin- diagnostic measures or the FTND. than one sentence or statement. cipal components analysis re- Overall, this measure is promising For instance, the item, “My vealed a 5-factor structure for the in that it can be used with paper- smoking pattern is very irregular NDSS (Shiffman et al. , 2004) as pencil administration and it has throughout the day. It is not predicted by the underlying theory. good reliability, but a meaningful unusual for me to smoke many Significant differences in the evaluation must await additional cigarettes in an hour, then not have scores on the subscales between validity research. another one until hours later,” White and African-American involves three negatives over its smokers suggest the scale may Multidimensional Measures of two sentences. In addition, some operate differently in subpopu- Tobacco Dependence questions are double-barrelled, lations, although there were no such as “It’s hard to estimate how ethnic differences in the total Nicotine Dependence Syndrome many cigarettes I smoke per day NDSS score (Shiffman et al ., Scale because the number often 2004). A more recent study, using changes.” If a person answers no, the 19-item questionnaire with the The Nicotine Dependence Syn- it is unclear whether the answer Finnish Twin Cohort Study drome Scale (NDSS) (Shiffman et refers to difficulty of estimation per population, found that a 3-factor al. , 2004) is a 19-item multi- se, or because the number of structure (priority/drive, continuity/ dimensional scale based on cigarettes smoked per day does stereotypy, and tolerance) best fit Edwards and Gross’ 1976 theory not change. Some items may be the data, with the internal of the significantly influenced by cultural consistencies of the three factors syndrome. The NDSS was factors, such as eating in ranging from 0.83 to 0.92 (Broms intended to complement, not re- restaurants that are smoke-free or et al. , 2007). place, traditional dependence experiences during air travel. measures, such as the DSM- These features may make the Validation : Much of the initial based assessments, and there- NDSS somewhat less appropriate validation work was done with the fore there is little content overlap than some other measures for 30- and 23-item NDSS, prior to its between the NDSS and the uni- individuals of modest reading being refined to the 19-item dimensional measures. The abilities or educational status. The version. These results indicated NDSS assesses five dimensions NDSS has been translated into that the NDSS-T predicted time to of nicotine dependence: “Drive” Finnish (Broms et al., 2007). lapse and time to relapse, but no reflects , withdrawal, and individual subscale predicted smoking compulsions; “Priority” Reliability and structure : To date, lapse or relapse (Shiffman et al. , reflects preference for smoking four studies of adult smokers have 2004). However, new data over other reinforcers; “Tolerance” generated data on the NDSS; one suggest that the NDSS subscales reflects reduced sensitivity to the study has reported on the NDSS are significantly, though modestly, effects of smoking; “Continuity” in adolescents aged 12-18 (Clark related to cigarettes smoked per reflects the regularity of smoking et al ., 2005). day (r = 0.12-0.26) and that the rate; and “Stereotypy” reflects the Psychometric data discussed Tolerance and Continuity sub- invariance of smoking (Appendix here are based on the revised 30- scales are modestly related to CO

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level (r = 0.12 and 0.13, smoking heaviness measures, different smoking dependence respectively) (Piper, et al ., 2008). other dependence measures, and motives: Affiliative Attachment, In samples of treatment-seeking smoking cessation likelihood Automaticity, Behavioral Choice/ smokers, the NDSS Priority and (Broms et al., 2007; Piper et al., Melioration, Cognitive Enhance- the Stereotypy subscales were 2008). The majority of this re- ment, Craving, Cue Expo- found to predict cessation out- search has been done on clinical sure/Associative Processes, Loss comes for up to 6-months populations and it is not known of Control, Negative Rein- post-quit (TTURC Tobacco how well these results would forcement, Positive Reinforce- Dependence Phenotype Work- generalize to population-based ment, Social and Environmental group, 2007; Piper, et al. , 2008). samples. There is evidence that Goads, Taste and Sensory The NDSS Drive, Tolerance, and the various subscales of the Properties, Tolerance, and Weight the total score were found to measure are differentially related Control (see Appendix 7 for the predict heaviness of smoking and to various dependence criteria items and scoring). The Flesch- cessation outcome in a popu- (Shiffman & Sayette, 2005; Broms Kincaid Reading Grade Level is lation-based sample of college et al ., 2007; TTURC Tobacco 4.6; however, balanced against students (Sledjeski et al ., 2007). In Dependence Phenotype Work- this easy reading level is the fact Finnish smokers, the NDSS was group, 2007). This suggests that that the total scale is quite long. significantly correlated with both some of the subscales possess Therefore, investigators might FTND and DSM-IV, as assessed discriminative validity with respect wish to use individual, theoretically by the CIDI measures of de- to different dimensions or aspects targeted subscales in epide- pendence (Broms et al ., 2007). of dependence. However, there is miologic research (subscales The NDSS subscales accounted evidence that the NDSS is not range from 4-7 items) (Lerman et for 51% of the variance in self- able to predict the major de- al ., 2006). Finally, relatively subtle reported difficulty abstaining pendence criteria of smoking psychological concepts are ad- among “chippers” (light/non-daily heaviness or cessation likelihood dressed in this measure, such as smokers) (Shiffman & Sayette, better than shorter measures thinking of cigarettes as a friend or 2005), with the Drive subscale (TTURC Tobacco Dependence experiencing a loss of control, and having the strongest relation ( β = Phenotype Workgroup, 2007). In this may affect the validity of such 0.61 ), relative to the other scales addition, the marginal reliabilities items in some cultures. There are (β = 0.13-0.28 ). of some of the subscales, and the English and Spanish versions of reading level and complexity of the WISDM (D.W. Wetter, Heritability : In the Finnish cohort, some of the items, may dis- personal communication, Decem- NDSS was found to have a courage use in large popu- ber 12, 2006). significant heritability estimate of lation-based samples. While all subscales assess 0.30, relative to a heritability dependence, it should be noted estimate of 0.40 for the FTND Wisconsin Inventory of Smoking that some of the subscales (i.e. (Broms et al ., 2007). Dependence Motives Cue Exposure/Associative Proce- sses, Social/Environmental Goads, Summary : Like the CDS, the The Wisconsin Inventory of and Taste/Sensory Properties) NDSS is a relatively new scale Smoking Dependence Motives represent early-onset motives, and it is not yet possible to draw (WISDM) (Piper et al. , 2004) is a which are present for all smokers firm conclusions about its validity 68-item measure developed to even at modest levels of smoking relative to other dependence assess the discrete motivational experience, while other subscales instruments. In its favour is the basis of dependence. This mea- represent late-onset motives (i.e. fact that some of its subscales sure has 13 theoretically-based Affiliative Attachment, Automa- have been shown to predict subscales designed to tap ticity, Behavioral Choice/ Melio-

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ration, Cognitive Enhancement, WISDM (TTURC Tobacco Depen- subscales may code for biological Craving, and Tolerance), which dence Phenotype Work-group, diversity so as to permit genetic are present only in individuals who 2007). mapping. smoke at a moderate daily rate or The various WISDM subscales have at least moderate smoking show different patterns of relations Summary : Like the CDS and the experience (Piper et al. , 2004). with the dependence criteria. For NDSS, the WISDM is a relatively instance, the Tolerance subscale new scale and it is too soon to Reliability and structure : To date, was the best predictor of CO level, draw firm conclusions about its only one study has published data but the Craving, Cue Exposure/ validity relative to other depen- on the WISDM (Piper et al. , 2004). Associative Processes, and dence instruments. However, data Across two different samples all Tolerance subscales were the reveal that some of its subscales 13 subscales had strong internal best predictors of DSM-IV depen- predict smoking heaviness consistencies that were evident dence when entered together into measures and smoking cessation across gender and across Whites a multiple regression equation likelihood (Piper et al. , 2008). and African-Americans. A new (Piper et al ., 2004). One study There is also evidence that the study found that the internal found that although the total score various subscales of the measure consistency of the subscales was not a significant predictor of are differentially related to various ranged from 0.74-0.94 with the relapse after controlling for dependence criteria (TTURC total scale having a Chronbach’s treatment, the combination of Tobacco Dependence Phenotype alpha of 0.96 (Piper et al ., 2008). Automaticity, Behavioral Choice/- Workgroup, 2007; Piper et al ., Factor analytic strategies indi- Melioration, Cognitive Enhance- 2008), suggesting that this mea- cated that the WISDM-68 is ment, and Negative Reinforce- sure is able to capture different multidimensional, although some ment subscales all predicted dimensions or aspects of depen- scales hit on related or over- relapse by the end of treatment in dence. However, there is evi- lapping dimensions of depen- a multivariate model (Piper et al. , dence that the WISDM is not able dence. Thus, it is safe to say that 2004). Data from two different to predict the major dependence some of the subscales are tapping smoking cessation trials found that criteria of smoking heaviness or the same underlying dimensions. WISDM Automaticity and Tole- cessation likelihood better than rance were predictive of outcome shorter measures (TTURC Validation : The total WISDM was at 6-months post-quit (TTURC Tobacco Dependence Phenotype correlated with smoking heaviness Tobacco Dependence Phenotype Workgroup, 2007). Some WISDM (cigarettes per day r = 0.63; CO r Workgroup, 2007). subscales have been related to = 0.55) (Piper et al ., 2004). Data various dependence-linked gene- also indicated that WISDM Total Heritability : There is evidence that tic components. It is important to predicted outcome at both 1-week the Taste/Sensory Properties note that the WISDM research has and 6-months post-quit (TTURC subscale was significantly related been done on clinical populations Tobacco Dependence Phenotype to a genetic variant that deter- and it is not known how well these Workgroup, 2007). Thus, there is mines sensitivity to bitter tastes results would generalize to evidence that the whole scale is (the phenylthiocarbamide (PTC) population-based samples. meaningfully related to the major haplotype) (Cannon et al. , 2005). dependence criteria. However, as Data have also revealed a Summary : with the NDSS, it appears that significant relation between the some shorter measures, such as WISDM Tolerance subscale with Assessment of cigarette-induced the HSI, predict smoking heavi- the ratio of 3-hydroxycotinine to nicotine dependence is an ness and cessation likelihood as cotinine (Piper et al. , 2008). These important goal for three reasons. well or better than the longer data suggest that some WISDM First, the human and economic

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costs of cigarette-induced, nico- dependence measures accounts public health outcomes. However, tine dependence is significant. for a large proportion of variance the relative lack of validity Second, only a portion of cigarette in outcomes in cessation information on these scales may smokers are “dependent” (as likelihood. This is no doubt due to mean that researchers should use defined by traditional instruments), the fact that cessation likelihood is these instruments only in the and those who are dependent are affected by countless situa- context of exploratory research. indeed distinguishable from other tional/environmental factors, and They might be most appropriate smokers on the basis of factors, other person factors. In addition, if for research addressing etiology such as likelihood of future one uses a brief measure, such as and cultural or population-based cessation and amount smoked the HSI, it is important to differences in smoking deter- daily. Finally, cigarette-induced recognize that it does not tap all minants. nicotine dependence may serve to dependence factors. It also does moderate individuals’ responses not appear to predict certain core Measures of smokeless to different tobacco control pro- features of dependence well, such tobacco-induced nicotine grammes and policies, as well as as withdrawal, and it may be dependence the proximal and distal effects of inappropriate in populations that these interventions. do not smoke daily or have Like cigarettes, smokeless tobac- It is important to note that there significant restrictions on smoking co (ST) products contain nicotine, is considerable evidence that the (e.g. restrictions that constrain although the levels vary con- various measures of nicotine smoking in certain contexts or siderably across products (Hatsu- dependence are not highly related times of day). kami et al ., 1992; IARC, 2007b). to one another, and can have very There may be situations when Data on patterns of use of ST different relations with validity there is a need to assess support the conclusion that many measures (Hughes et al., 2004a; particular, relatively discrete, users are nicotine dependent Piper et al. , 2006). Thus it is facets of nicotine dependence. (Henningfield et al. 1997; IARC, critical that investigators select For example, identifying specific 2007b). Many ST users experi- measure(s) that are psycho- tobacco dependence mechanisms ence withdrawal symptoms upon metrically sound, appropriate for may facilitate: identification of a abstinence (Hatsukami et al. , the intended population, and more proximal phenotype (Can- 1992; 1999). Studies have used a target the constructs in which the non et al. , 2005), identification of biomarker of nicotine uptake, researchers are interested. If the specific dependence dimensions cotinine, to show that daily users goal is to assess a central core of with which one could create of ST exhibit levels of nicotine nicotine dependence as a pre- treatment algorithms, monitoring absorption that are equivalent to dictor of cigarette use cessation of the development of tobacco daily cigarette smokers (Gritz et likelihood, or as an index of dependence, or identification of a al. , 1981). associated health risks, then the specific group of dependent Dependence on smokeless FTND or HSI appear best suited tobacco users for whom a policy is tobacco has often been assessed for this purpose (Tables 3.22 and particularly effective or ineffective. with questionnaires derived from 3.23). These instruments are brief If this is the goal of the research, FTND, with the addition of specific and have relatively impressive then a multifactorial measure (i.e. items, in particular, swallowing the predictive validities, and their the NDSS and the WISDM-68, tobacco juice (Boyle et al. , 1995; reading level should make them and their subscales) would be Ebbert et al., 2006). In three appropriate for a broad range of optimal, despite the fact that there different samples, use of ST within populations. However, it is is little evidence for incremental 30 minutes of waking and important to note that none of the validity in predicting important swallowing the tobacco juice were

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Construct Tobacco Dependence

Measure 1 Fagerström Test of Nicotine Dependence (FTND) – 6 items

Source Heatherton et al ., 1991

Variation It is possible to change the wording of the items to be culturally appropriate or to reflect non-cigarette tobacco use. However, these changes may affect the reliability and validity of the data obtained.

Validity • Predicts both behavioural (e.g. lifetime amount smoked) and biochemical (e.g. CO, cotinine) indices of smoking in multiple countries • Predicts cessation • Evidence of linkage to specific dependence-linked genetic variants

Comments This measure is recommended as an assessment of dependence’s ability to predict cessation and heavy use • Brief and well-known • Strong predictive validity of heavy use and cessation • Internal consistency is modest, which may reflect a 2-factor structure • Some items may be influenced by smoking restrictions in the environment • Has been translated into a number of different languages

Measure 2 Heaviness of Smoking Index (HSI) – 2 items from the FTND: number of cigarettes smoked per day and time to first cigarette in the morning

Source Kozlowski et al. , 1994

Variation It is possible to change the wording of the items to be culturally appropriate or to reflect non-cigarette tobacco use. However, these changes may affect the reliability and validity of the data obtained.

Validity • Predicts both behavioural (e.g. lifetime amount smoked) and biochemical (e.g. CO, cotinine) indices of smoking in multiple countries • Predicts cessation – the HSI appears to be the strongest predictor of cessation, accounts for much of the predictive validity of the FNTD • Highly heritable (71%) and linked to specific dependence-linked genetic variants

Comments This measure is recommended as the most efficient measure to assess dependence’s ability to predict cessation. • Brief • Using this measure may only involve the addition of item (time to first cigarette) if number of cigarettes per day is already being collected • Strong predictive validity of heavy use and cessation • Items may be influenced by smoking restrictions in the environment • Has been translated into a number of different languages

Table 3.22 Measures of Cigarette-Induced Nicotine Dependence

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Construct Tobacco Dependence

Measure Fagerström Test of Nicotine Dependence (FTND) – 6 items

Sources Boyle et al. , 1995; Ebbert et al ., 2006

Variation It is possible to change the wording of the items to be culturally appropriate or to reflect non-cigarette tobacco use. However, these changes may affect the reliability and validity of the data obtained.

Validity • Predicts both behavioural (e.g. lifetime amount smoked) and biochemical (e.g. CO, cotinine) indices of smoking in multiple countries • Predicts cessation • Evidence of linkage to specific dependence-linked genetic variants

Comments This measure is recommended as an assessment of dependence’s ability to predict cessation and heavy use • Brief and well-known • Strong predictive validity of heavy use and cessation • Internal consistency is modest, which may reflect a 2-factor structure • Some items may be influenced by smoking restrictions in the environment • Has been translated into a number of different languages

Table 3.23 A Measure of Smokeless Tobacco-Induced Nicotine Dependence

the variables most consistently to provide a means for identifying measures of cigarette and smoke- associated with cotinine level ST users who are nicotine depen- less tobacco nicotine depen- (Boyle et al. , 1995) (see Appendix dent. dence. For cigarette smoking, the 8 for the items and scoring). 2-item Heaviness of Smoking Summary and recommenda- Index is recommended for use in Summary : tions population level studies. If only a single item measure is possible, Like cigarettes, smokeless to- Nicotine dependence is an the use of “time to first cigarette in bacco can result in nicotine important construct to assess as a the morning” is recommended. dependence. While less research moderator for the effects of For smokeless tobacco, the has been done to validate self- tobacco control programmes and FTND-ST appears to be a useful report measures of ST-induced policies. In this section the measure of nicotine dependence. nicotine dependence, question- evidence was reviewed on the naires derived from FTND appear validity of various proposed

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