Do researcher-derived classifications of youths' smoking behavior correspond with youths' characterizations of their behavior?

Addictive Behaviors 34 (2009) 984–992

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Addictive Behaviors

Short communication

Do researcher-derived classifications of youths' smoking behavior correspond with youths' characterizations of their behavior? Chizimuzo T.C. Okoli a,b,⁎, Pamela A. Ratner b, Rebecca J. Haines b, Kelli M. Sullivan b,c, Su-Er Guo b,d, Joy L. Johnson b a

British Columbia Centre of Excellence for Women's Health, E311 - 4500 Oak Street, Box 48 Vancouver, BC Canada V6H 3N1 NEXUS, University of British Columbia, 302-6190 Agronomy Road, Vancouver, BC Canada V6T 1Z3 Faculty of Health & Social Development, University of British Columbia-Okanagan, Kelowna, BC Canada V1V 1V7 d School of Nursing, University of Victoria, PO Box 1700, Victoria, BC Canada V8W 2Y2 b c

a r t i c l e

i n f o

Keywords: Adolescent tobacco use Smoking categories Smoking status Youth smoking behavior Measurement

a b s t r a c t Aims: To describe the categories employed by researchers to describe adolescents' smoking behavior and to determine how these various categorizations compare with youths' self-defined smoking status. Study selection: A search of the PubMed and Science Direct databases, limited to articles in the English language, published between January 2002 and November 2007. Data extraction: Employing a mixed methods approach, several categories of youths' smoking status were obtained from a literature review and subsequently reproduced by using responses to detailed questionnaire items. Associations between the researcher-derived smoking categories (from the literature review) and the youths' self-reported smoking status, from survey data, were determined. Results: The categories of smoking status, from the literature review, varied in definition and in the number of categories. The associations between the literature-based categories and the youths' self-reported smoking status were modest. Conclusions: Researcher-derived categories of youths' smoking status may not adequately encapsulate youths' perceptions of their own smoking behavior. There is a need to better describe adolescents' smoking behavior with special consideration of the ways in which adolescents characterize their own smoking behavior. © 2009 Elsevier Ltd. All rights reserved.

1. Introduction With current understanding of the progressive stages of youths' tobacco use (Karp, O'Loughlin, Paradis, Hanley, & Difranza, 2005), there is increasing variation in researchers' classifications of smoking behavior. This problem in classifying youths' smoking behavior has resulted in ever more varied terminology (Mayhew, Flay, & Mott, 2000) and overlapping concepts to describe the various transitional phases of smoking. Without the establishment of proper classifications for youth smoking behavior (Health Canada, 2005), this proliferation of terminology limits meaningful comparisons across study findings. However, to date, few reviews [see Mayhew et al. (2000)] have addressed the various classifications of adolescents' smoking behavior. Recent studies indicate that researcher-derived classifications (i.e., categorizations of youth based on smoking behavior by researchers, but not defined by youths) may disagree with youths' characterizations of their own smoking behavior (Delnevo, Lewis, Kaufman, & Abatemarco, 2004; Rubinstein, Halpern-Felsher, Thompson, & Millstein, 2003). Such disagreements between researchers' classifications and youths' char-

acterizations may result in inappropriate interventions being targeted to youths who do not subscribe to, or identify with, researchers' or healthcare providers' classifications. For example, Leatherdale and McDonald (2006) found that about 52% of students that were categorized as ‘regular smokers’ and 98% categorized as ‘experimenters’ did not actually consider themselves to be smokers. Such divergence between youths' and researchers' definitions of smoking needs to be addressed before appropriately tailored smoking interventions can be targeted to their intended audiences (Backinger et al., 2003). Building on our recent study on the validity of youths' smoking identities (Okoli, Richardson, Ratner, & Johnson, 2008), the purpose of this study was to conduct a comprehensive review of the current literature to: a) describe differences in the operational definitions of the smoking behavior classifications employed by researchers and b) determine how these various classifications compare with youths' self-reported smoking status/identity.

2. Methods ⁎ Corresponding author. Research Associate-Tobacco British Columbia Centre of Excellence for Women's HealthE311 - 4500 Oak Street, Box 48 Vancouver, BC Canada V6H 3N1. E-mail address: [email protected] (C.T.C. Okoli). 0306-4603/$ – see front matter © 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.addbeh.2009.05.012

This study employed a mixed methods approach in two steps: a) a literature review to obtain pertinent researcher-derived categories of youth smoking and b) a reproduction and comparison of these

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categories with youths' self-selected smoking identities derived from an existing survey dataset.

were performed using the Statistical Package for the Social Sciences (SPSS) version 14.

2.1. Selection of research studies

3. Results

A search of the PubMed and Science Direct databases was conducted to identify published articles that addressed youth smoking behavior (see Appendix). The search was limited to articles assessing the cigarette smoking of adolescents, written in the English language, and published within the last 5 years (January 2002– November 2007). For the purposes of the current study, longitudinal studies were excluded to limit any unnecessary repetition of the smoking categories and to avoid potential, unknown changes in smoking status/identity over time that may occur in longitudinal studies. A total of 564 studies were obtained (see Appendix) through our literature search, of which 66 publications met the inclusion criteria. To organize the youth smoking classifications identified in the literature, the results of our review are presented in the following groupings: 1) Never Smokers vs. Ever Smokers, 2) Nonsmokers vs. Smokers, 3) Nonsmokers/Never Smokers vs. Current Smokers, 4) Ex-smokers/ Former Smokers/Quitters, 5) Experimenters/Experimental Smokers/ Triers, 6) Non-regular Smokers vs. Regular /Established Smokers (see Result section). These groupings were selected to describe the overall differences within and between classifications as they progress from simple, general categorizations to more complex, detailed categorizations of youths' smoking behavior.

3.1. Never smokers vs. ever smokers

2.2. Measures In the survey dataset, the youths' characterizations of their behavior were their responses to the question, “How would you define yourself?” Nine response options were offered: “I am a… ‘nonsmoker', ‘occasional smoker’, ‘irregular smoker’, ‘regular smoker’, ‘heavy smoker’, ‘social smoker’, ‘ex-smoker’, ‘pot smoker’ and ‘other, specify’.” For this paper, we examined the responses related only to tobacco use. Classifications of youths' smoking were obtained from the literature search. Fifty-one smoking categories were obtained from the reviewed articles (see Table 1). Due to insufficient variable information in the survey dataset, we could not replicate all categories found in the published literature. However, where possible, we approximated the operational definitions of the researcher-derived classifications to reconstruct the categories and were able to recreate 38 of the 51 categories. 2.3. Data analysis The data were obtained from the British Columbia Youth Survey on Smoking and Health II; a study involving self-administered questionnaires completed by 8225 adolescents in grades 7–12 in schools in British Columbia, Canada, in 2004 (Hutchinson, Richardson, & Bottorff, 2008; Okoli et al., 2008; Tu, Ratner, & Johnson, 2008). The study was approved by the University of British Columbia Behavioural Research Ethics Board. Of the 8225 students in the original sample, 15.5% had missing responses, gave incongruent responses, reported using tobacco products other than cigarettes, or selected multiple smoking identities. Because the focus of our analysis was on adolescents with a single smoking identity, the present report is based on data obtained from 6950 adolescents (84.5% of the original sample). A contingency coefficient (Pearson's C) was estimated to measure and compare the strength of association between researchers' smoking classifications and the youths' characterizations of their smoking behavior, with higher values indicating a relatively stronger association (see Table 1). The analyses for contingency coefficients

Forty-eight percent (n = 32) of the reviewed studies used the term never smokers, as compared with 16.6% (n = 11) of studies that used the term ever smokers (or ‘life-time smoker’). When comparing the never smoker vs. ever smoker grouping with the youths' self-reported smoking status (n = 11 studies), associations ranged from .49 to .61. 3.2. Nonsmokers vs. smokers Fifty six percent (n = 37) of the reviewed studies used the term nonsmoker (or ‘current nonsmoker’), as compared with 18% (n = 12) of studies that used the term smoker. In comparing the nonsmoker vs. smoker grouping with the youths' self-reported smoking status (n = 8 studies), associations ranged from .45 to .63. 3.3. Nonsmokers/never smokers vs. current smokers Fifty-nine percent (n = 39) of studies used the term current smoker. In comparing the nonsmokers/never smokers vs. current smokers with the youths' smoking identities (n = 15 studies), associations ranged from .44 to .64. 3.4. Ex-smokers/former smokers/quitters Twenty-seven percent (n = 18) of the reviewed studies used either ex-smoker, current nonsmoker, former smoker, quitter, past smoker, or previous smoker to identify youths who had prior experience with smoking but had either ceased, or were not currently engaged in such behavior. Associations between the youths' self-reported smoking status and the research-derived classifications of never/nonsmoker vs. ex-smoker/former smoker/quitter vs. current smoker (n = 6 studies) ranged from .62 to .67. 3.5. Experimenters/experimental smokers/triers Thirty-two percent (n = 21) of the reviewed studies employed the terms, experimenter (n = 10), trier (including ‘tried once’ and ‘tried smoker’, n = 6), or experimental smoker (n = 5) to identify youths who had novice experience with smoking. Associations between the youths' smoking identities and nonsmoker/never smoker, experimenter/ experimental smoker/trier and current smoker (n=3 studies) ranged from .49 to .66. Associations between the youths' smoking identities and nonsmoker/never smoker, experimenter/experimental smoker/ trier, former/ex-/past smoker, and current smoker (n=7) ranged from .66 to .68. 3.6. Non-regular smokers vs. regular/established smokers Twenty percent (n = 13) of the reviewed studies used either nondaily smoker, thirty day ever smoker, situational smoker, social smoker, occasional smoker/current occasional smoker, sporadic smoker, or non-regular smoker to identify youths who were currently engaged in smoking behavior but not on a regular or established basis. Conversely, 33.3% (n = 22) of the studies employed the terms daily smoker, weekly smoker, monthly smoker, established smoker, or regular smoker/current regular smoker to classify those whose smoking was more frequent and persistent. Associations between the youths' smoking identities and the researcher-derived categories including non-regular and regular smoker categories in addition to

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Table 1 Associations between researcher-derived classifications of youth smoking behavior and youth self-reported smoking identity (N = 6950). Category and reference

Smoking statusa

Operational definition

Pearson's Cb

1 (Laugesen, Scragg, Wellman, & DiFranza, 2007; Leatherdale, Cameron, Brown, Jolin, & Kroeker, 2006; Lejuez, Aklin, Bornovalova, & Moolchan, 2005; Shakib et al., 2003) 2 (Fernander et al., 2006)

Never smoker Ever smoker

Never smoked a cigarette, not even one puff Has smoked a cigarette, even a puff

.49

Never smoker Ever smoker Former

Has never smoked a whole cigarette Has smoked a whole cigarette Has smoked at least one cigarette in lifetime but not in the past 31 days Has smoked in the past 31 days Has never smoked Has ever smoked Has smoked once or several times Smokes sometimes or every day Has never tried even a puff of a cigarette, and has not smoked in the past 30 days

.61 (never vs. ever)

3 (X. Liu, 2003)

4 (Anderson, Pollak, & Wetter, 2002; Vidrine, Anderson, Pollak, & Wetter, 2005)

5 (Ozge, Toros, Bayramkaya, Camdeviren, & Sasmaz, 2006; Sun et al., 2006)

6 (O'Loughlin et al., 2003)

7 (Breslin & Adlaf, 2002; Geckova, van Dijk, Honcariv, Groothoff, & Post, 2003; Golan et al., 2004) 8 (Winter, de Guia, Ferrence, & Cohen, 2002)

Current smoker Never smoker Ever smoker Experimenter Current smoker Never smoker Nonsusceptible⁎ Susceptible⁎ Ever smoker Experimenter Current smoker Never smoker Life-time smokers Past smoker Current Non-daily smoker Daily smoker Never smoker Ever smoker Former smokers⁎⁎ Current smokers⁎⁎ Triers Sporadic smokers Monthly smokers Weekly smokers Daily smokers Nonsmoker Smoker Nonsmoker Smoker

9 (Wilson et al., 2005)

Nonsmoker Smoker

10 (Jacobsen et al., 2005)

Nonsmoker Smoker Nonsmoker Smoker Nonsmoker Smoker

11 (Caraballo, Giovino, & Pechacek, 2004) 12 (Panter & Reeve, 2002)

13 (Siegel, Alvaro, & Burgoon, 2003)

14 (Al-Haddad & Hamadeh, 2003)

15 (J. Liu et al., 2007)

Nonsmoker⁎ At risk nonsmoker⁎ Smoker Nonsmoker Never smoker Ex-smoker Smoker Nonsmoker Never smoker Former smoker Smoker

.67 (never, former, current)

.49 (never vs. ever)

.49 (never vs. ever) .66 (never, experimenter, current)

Has smoked, even one puff Has tried smoking, but has not smoked in the past 30 days Has tried smoking and has smoked in the past 30 days Has never smoked Has smoked at least once in life-time Has smoked in the past, but not in the past 30 days Has smoked in the past 30 days Smoked in past 30 days but not daily Smoked in past 30 days and daily Have never smoked, not even a puff Has ever smoked, even a puff (Did not smoke in the past 3 months)

.49 (never vs. lifetime) .66 (never, past, current) .69 (never, past, non-daily, daily,) .49 (never vs. ever) .72 (never, trier, sporadic, monthly, weekly, daily)

(Smoked in the past 3 months) Smoked 1–2 times in lifetime Smoked ≥3 times in lifetime, but not monthly, weekly, or daily Smoked ≥1 times in each of the past 2 or more months, but not weekly or daily Smoked ≥1 times each week but not daily Smoked every day Does not smoke more than one cigarette per day Smokes one or more cigarettes a day “Never” smokes or has smoked only one cigarette in the past 12 months Has smoked more than one cigarette in the previous 12 months. Has never tried smoking Has tried smoking, smoked a whole cigarette, smoked ≥ 1 day in the past month Has not smoked more than 2 cigarettes in lifetime Smokes daily Has not smoked any cigarettes in the past 5 days Has smoked one or more cigarettes in the past 5 days Has never smoked or did not smoke within the last 30 days Has smoked 100 or more cigarettes in lifetime and has smoked in past 30 days Has not smoked 100 cigarettes in lifetime and has not smoked in past 30 days Has not smoked 100 cigarettes in lifetime and has not smoked in past 30 days Has smoked in the past 30 days Never smoked and ex-smokers combined Has never smoked Has smoked, but was not smoking at the time of the study. Was smoking any amount of tobacco at the time of study Never smoker and former smoker combined Has smoked no more than 2 cigarettes in lifetime and none in the past month Has smoked regularly in the past, but has not smoked in past 3 months Currently smokes monthly or has smoked in the past 30 days

.54

.63

.49

.66 (n = 6018)c .58 .45

.64 (n = 6870)c

NR

.66 (n = 6709)c

.66 (never, former, smoker, n = 6709)c

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Table 1 (continued) Category and reference

Smoking statusa

Operational definition

Pearson's Cb

16 (Patten et al., 2003)

Nonsmoker

Has smoked none or less than 100 cigarettes in lifetime Never inhaled the smoke of a cigarette Has smoked greater than 1 but less than 100 cigarettes

.58 (nonsmoker vs. smoker)

Never smoker Experimenter Smoker

17 (Zbikowski, Klesges, Robinson, & Alfano, 2002) 18 (Kalesan, Stine, & Alberg, 2006)

19 (Taylor, Conard, Koetting O'Byrne, Haddock, & Poston, 2004) 20 (Baer Wilson & Nietert, 2002; Camenga, Klein, & Roy, 2006; Johnson et al., 2004; Kitsantas, Moore, & Sly, 2007; Pokorny, Jason, & Schoeny, 2004; Tyc et al., 2004; Tyc, Lensing, Klosky, Rai, & Robinson, 2005) 21 (Duhig, Cavallo, McKee, George, & Krishnan-Sarin, 2005)

Has smoked more than 100 cigarettes and has smoked in the past 30 days Former smokers Has smoked greater than 100 cigarettes in lifetime but none in the past 30 days Current smokers Has smoked greater than 100 cigarettes and smoked in the past 30 days Never smoker Has never smoked (not even a puff) Current smoker Smokes one or more cigarettes per month Never smoker Has never puffed, has no intention to smoke, and has not smoked every day for 30 days Current Smoker Has smoked cigarettes every day for 30 days Current Has never smoked and does not smoke regularly Nonsmoker or occasionally Current Smoker Smokes regularly or occasionally Nonsmoker Has not smoked in the last 30 days Current smoker Has smoked in the last 30 days

.66 (never, experimenter, former, current)

Nonsmoker Current smoker

22 (Morris, Zhang, & Bondy, 2006)

Nonsmoker Current smoker

23 (Bratberg, Nilsen, Holmen, & Vatten, 2007) 24 (Bush et al., 2007)

Nonsmoker Current smoker Nonsmoker Nonsusceptible⁎ Susceptible⁎ Current Smoker

25 (Centers for Disease Control and Prevention, 2006)

26 (Miller, Burgoon, Grandpre, & Alvaro, 2006; Primack, Gold, Land, & Fine, 2006; Primack et al., 2006)

27 (Kitsantas et al., 2007)

28 (Aloise-Young, Cruickshank, & Chavez, 2002)

29 (Huebner et al., 2005)

30 (Caraballo, Yee, Gfroerer, Pechacek, & Henson, 2006)

Nonsmoker

Has never been a daily smoker and has not used tobacco in the past 6 months Has smoked cigarettes on at least 1 day in the past month Has not smoked 100 cigarettes in lifetime and has not smoked in past 30 days Has smoked 100 cigarettes in lifetime and smoked in the past 30 days Has never smoked cigarettes or has stopped smoking Has ever smoked and smokes daily or occasionally Has not smoked 100 cigarettes in lifetime and has not smoked in past 30 days

Has smoked 100 cigarettes in lifetime and smoked in the past 30 days Has not smoked part or a whole cigarette in the last 30 days

Nonsusceptible⁎ Susceptible⁎ Current Smoker Nonsmoker

Has smoked part or a whole cigarette in the past 30 days Has not smoked in the past 30 days

Nonsusceptible⁎ Susceptible⁎ Current Smoker Nonsmoker

Has smoked in the past 30 days Has not smoked in past month

Non-intentional Intentional Current smoker Situational smoker Established smoker Nonsmoker Current nonsmoker Current smoker Never smoker Former smoker Current smoker Never smoker Non-susceptible Susceptible Previous smoker Current smoker

Does not intend to smoke in the next year Intends to smoke in the next year Has smoked in the past 30 days Has smoked less than five or more cigarettes per day on six or more days in the past month Has smoked five or more cigarettes per day on six or more days in the past month Has never smoked Has smoked but not in the previous 30 days Has smoked in the previous 30 days Has never smoked a cigarette Has smoked at least one cigarette in lifetime but not in the past 30 days Has smoked in the past 30 days Never smoked cigarettes in lifetime

.69 (n = 5127)c .54

NR

.64

NR

.44

NR .44 (Nonsmoker vs. Current smoker)

.64 (Nonsmoker vs. Current smoker)

.64 (Nonsmoker vs. Current smoker)

.64 (Nonsmoker vs. Current smoker)

.66

.66

.66 (never, previous, current)

Has smoked one or two cigarettes in lifetime but not in the previous month Has smoked all or part of a cigarette in the previous month (continued on next page)

988

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Table 1 (continued) Category and reference

Smoking statusa

Operational definition

Pearson's Cb

31 (Patten et al., 2004)

Nonsmoker

Has smoked none or less than 100 cigarettes in lifetime

.62 (nonsmoker, former smoker, current smoker)

Never smoker Experimenter Former smoker Current smoker 32 (Leatherdale, Manske, & Kroeker, 2006)

Never smoker Occasional smoker Regular smoker

33 (Murnaghan, Sihvonen, Leatherdale, & Kekki, 2007)

Never smoker Occasional smoker Regular smoker Nonsmoker Occasional smoker Regular smoker Nonsmoker Occasional smoker Daily smoker Non-smoker

34 (Skalle & Rise, 2006)

35 (Griesbach, Amos, & Currie, 2003)

36 (Victoir, Eertmans, Van den Broucke, & Van den Bergh, 2006)

Never smoker Experimenter

37 (Yakir et al., 2007)

Occasional smoker Daily smoker Non-smokers Current smokers Past smokers

38 (Brook, Morojele, Brook, Zhang, & Whiteman, 2006)

39 (Reynolds, Karraker, Horn, & Richards, 2003)

40 (Wen et al., 2007)

Occasional smoker Nonsmoker Experimental smoker Regular smoker Never smoker Trier Current smoker Never smoker Experimental smoker Regular smoker

41 (Poorasl, Vahidi, Fakhari, Rostami, & Dastghiri, 2007)

Never smoker Experimenter

42 (Lai, Ho, & Lam, 2004)

Established smoker Never smoker Experimental smoker

43 (Szabo, White, & Hayman, 2006)

Current smoker Non-susceptible nonsmoker Susceptible nonsmoker Experimental smoker Current smoker

Has never smoked Has smoked less than 100 cigarettes in lifetime Has smoked 100 or more cigarettes in lifetime but none in the past 30 days Has smoked 100 or more cigarettes in lifetime and has smoked in past 30 days Has never smoked a cigarette, not even a puff Has smoked more than once in the past 30 days but not every day or almost every day Has smoked every day or almost every day in the past 30 days Has never smoked or has only tried smoking once Smokes less than weekly Smokes every week Has never smoked Seldom smokes or has quit smoking Smokes every day, 3–5 times a week, or 1–2 times a week Does not smoke currently Smokes less than once a week or at least once a week but not every day Smokes every day Does not smoke — “I do not smoke” Has never touched a cigarette Has smoked at least once

.66 (never, experimenter, former, current)

.73 (n = 5076)c

.71 (n = 5076)c

NR

.68 (n = 6899)c

.70 (non-, occasional, daily, n = 6508)c .71 (never, experimenter, occasional, daily, n = 6512)

Smokes occasionally, but not every day Smokes every day Had never smoked a single cigarette during their lifetime Smoked on a regular basis at the time of testing Smokes on a regular basis but had been fully abstinent for a minimum of 6 months Smoked from time to time but not on a regular basis Has never tried smoking Has tried a few puffs but smokes less than a few cigarettes per week Smokes a few cigarettes/week to greater than a pack/day Had not tried smoking even one cigarette Had tried cigarettes for the first time during the past 6 months Had smoked every week for at least 6 months Has never smoked cigarettes, even one or two puffs Has smoked cigarettes, even one or two puffs but has not smoked at least once per week over 3 months' duration Has smoked cigarettes, even one or two puffs and has smoked at least once per week over 3 months' duration Has never tried a cigarette, not even a few puffs Has smoked less than 100 cigarettes in lifetime, even just a few puffs Has smoked greater than 100 cigarettes in lifetime, irrespective of current smoking status Has never smoked Has not smoked in the past 30 days (including individuals who had tried smoking in the past and some who used to smoke previously but no longer do) Has smoked in the past 30 days Has never smoked and is certain not to smoke Has never smoked but is uncertain about smoking in the future, or had had a puff of a cigarette and was certain not to smoke again Has had a puff of a cigarette and is uncertain of not smoking again or has smoked fewer than 100 cigarettes in lifetime and has not smoked in the preceding week Has smoked during the previous 7 days or has smoked more than 100 cigarettes and smoked in the previous month

NR

NR

NR

NR

.62

.66

.67 (n = 6694)c

c

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989

Table 1 (continued) Category and reference

Smoking statusa

Operational definition

Pearson's Cb

44 (Peters et al., 2006)

Nonsmoker Quitter

Has never smoked even part of a cigarette Used to smoke regularly but quit over 12 months ago or quit within the last 12 months Has smoked part of a cigarette or smoked a few times Currently smokes about 1 cigarette every other week, up to, smoke more than a pack a day

NR

Experimenter Current smoker 45 (Castrucci, Gerlach, Kaufman, & Orleans, 2002)

46 (Kaufman et al., 2002)

Non-susceptible never smoker⁎ Susceptible never smoker⁎ Experimenter Former smoker Current smoker Never smoker

Has never smoked a cigarette but taken at least one puff Has smoked a cigarette but not in the past 30 days Has smoked a cigarette and has smoked in the past 30 days

former, current

Has never smoked a cigarette nor tried or experimented with smoking, even a few puffs

.68 (never, former, experimenter, current) .71 (never, former, experimenter, non-regular, regular)

Non susceptible⁎ Susceptible⁎ Former smoker⁎⁎ Nonsmoking intender Smoking intender Experimenter Current smoker⁎⁎ Non-regular smoker Regular smoker 47 (Grimshaw et al., 2003)

Never smoker Ex-smoker Tried smoker

48 (Sasco, Merrill, Benhaim-Luzon, Gerard, & Freyer, 2003)

49 (Ellison et al., 2006)

Current occasional smoker Current regular smoker Never smoker Former smoker Occasional smoker Regular smoker Never smoker Trier Former smoker Current smoker Social smoker

50 (Leatherdale & McDonald, 2006)

Regular smoker Never Smoker Nonsusceptible⁎ Susceptible⁎ Tried Once Experimental Regular smoker

51 (Panday, Reddy, Ruiter, Bergström, & de Vries, 2007)

Established smoker Never smoker Nonsmoking decider Quitter Trier Monthly smoker Weekly smoker

.68 (nonsmoker = nonsusceptible + susceptible, experimenter,

(Has previously smoked a cigarette but not in the past 30 days) Not intending to smoke in the next year Intends to smoke in the next year Has never smoked a whole cigarette but has tried smoking (Has smoked in past 30 days) Has smoked 1–99 cigarettes in life time and smoked in the last 30 days Has smoked more than 100 cigarettes during lifetime and has smoked in the past 30 days Has never tried a cigarette Does not smoke cigarettes at all nowadays and has smoked at least one cigarette every day sometime in the past Has tried smoking but has never smoked at least one cigarette every day Smokes nowadays but does not smoke at least one cigarette every day

NR

Smokes at least one cigarette every day Has never smoked or has tried only one time Has smoked, but does not smoke now Smokes from time to time, but less than one cigarette/ week Smokes weekly Never smoked in lifetime Has smoked less than 100 times in lifetime but not in the past 30 days Has smoked more than 100 times in lifetime but not in the past 30 days Has smoked in the past 30 days Has smoked on at least one, but no more than 21 days of the previous 30 days Has smoked on at least 22 days of the previous 30 days Has never smoked a cigarette, not even a puff

NR

.68 (never, trier, former, current) .71 (never, trier, former, social, regular)

.71 (n = 6417)

Has tried a puff of only 1 or 2 cigarettes and did not smoke in the past 12 months Has smoked more than once, smoked less than monthly, and has smoked less than 100 cigarettes in lifetime Has smoked more than once, smoked in the past month, and has smoked more than 100 cigarettes in lifetime Smokes everyday or almost everyday Never smoked, not even one puff Tried smoking less than once a week but not smoking anymore

NR

Quit smoking after having smoked at least once a week Tried smoking once in a while but not monthly Smoking at least once a month, but not weekly Currently smoking cigarettes weekly or more (continued on next page)

990

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nonsmoker/never smoker, former/ex-/past smoker, experimenter/ experimental smoker/trier (n = 4 studies), ranged from .69 to .72. 4. Discussion Mismatches between smoking categorizations used by researchers and youths' definitions of their own smoking behavior could potentially result in faulty study conclusions and misdirected smoking prevention or cessation interventions (Leatherdale & McDonald, 2006). Our present study indicates that the literature about adolescents' smoking behavior not only contains inconsistent nomenclature but also employs smoking behavior classifications that do not wholly match youths' characterizations of their own smoking behavior. Although there were conceptual similarities within the youth smoking classifications described in the literature, some marked differences existed in their operational definitions, with significant overlap between some categorizations. For example, a never smoker defined in Category 15 (see table) may have been classified in other studies as an ever smoker (Categories 1–6), or smoker (Category 9). Moreover, there was an increasing strength of association between the researcher-derived classifications of smoking status and the youths' characterizations of their smoking behavior as the number of categories within a classification scheme increased. For example, whereas the strongest association between a two-category researcher-derived classification and the youths' characterizations of their own behavior was .64 (Categories 20, 25–27), the association between a 6-category researcher-derived classification and the youths' responses was .72 (Category 6). This suggests that using more sophisticated or multifaceted classifications of the youths' smoking may better match their self-reported smoking identities. 5. Recommendations The intent of this study was not to promote or denounce any existing classifications of youth smoking behavior; rather, we sought to describe the degree to which classifications of adolescents' smoking behavior vary in the literature, and correspond with youths' characterizations of their behavior. Our findings are limited by the smoking categories we obtained from the published literature and the classifications that could be replicated from the variables in our existing database. In addition, differences in youths' smoking identities by age, gender, ethnic identity, or other substance use were not examined. Thus, the recommendations from our findings should be taken with these potential confounding factors in consideration.

Based on our findings, we offer the following recommendations: 1. Consensus for the classification and operational definition of youths' smoking behavior need to be established, specifically in the context of tobacco use prevention and cessation programs. Mermelstein (2003) noted that if smoking cessation interventions are to be effective, ‘smokers’ have to acknowledge their smoking behavior, self-identify as a smoker, and have some realization that messages about and interventions for smoking apply to them. In a similar fashion, we would argue that for effective smoking cessation interventions for youth, interventionists must achieve some consensus to define youths' smoking behavior, recognize how youth self-identify as smokers, and design messages in a way that permit youths to recognize that the programs are for them. 2. Research addressing adolescents' smoking behavior may be advanced if researchers included questions about the perceived smoking status/identity of the target group. For example, if a researcher is interested in classifying youth into the categories of nonsmoker, experimental smoker, and current smoker, regardless of the operational definitions used to derive these categories, an accompanying question (e.g., “How would you describe your smoking status…?” with response choices of “nonsmoker,” “experimental smoker,” or “current smoker”) should permit the youth to self-select their smoking status/identity affiliation. Studies may also indicate how well (by using some measure of agreement such as a kappa statistic or Pearson's C) the classifications used by researchers match youths' characterizations of their own smoking behavior. 6. Conclusions and future directions Despite advances in understanding adolescents' smoking behavior, future studies are needed to refine the classifications and operational definitions of the various behaviors observed. Kishchuk, Tremblay, Lapierre, Heneman, & O'Loughlin (2004) highlighted that smoking cessation programs often face the challenge of recruiting participants from a population that may not perceive the need for intervention. Hence, effective smoking cessation interventions for youth should take into consideration the characteristics of the individual adolescent and the macro-environment surrounding adolescents' smoking (Mermelstein, 2003). The findings of our review suggest the need for consensus in the research community to better describe adolescents' smoking behavior with special consideration of the ways in which adolescents self-identify their smoking behavior. Future studies addressing the greater macro-environment surrounding adolescents' smoking in relation to the development and changes in smoking identity could enhance our understanding of youths' smoking behavior. Such an understanding can improve the ways in

Table 1 (continued) Category and reference

Smoking statusa

Operational definition

Pearson's Cb

Notes to Table 1: ⁎A Nonsmoker has not smoked 100 cigarettes in life time, has not smoked in past 30 days and answered “definitely not” to the following three questions: (a) Intend to smoke a cigarette within the next year, (b) Would smoke a cigarette offered from a friend, and (c) Might try a cigarette soon. An At-risk nonsmoker did not answer ‘definitely not’ to all three questions. ⁎A non-susceptible never smoker responded ‘definitely not’ to all of the following questions: (1) Do you think you might smoke in response to an offer for a cigarette from one of your best friends? (2) Do you think you might smoke any time during the next 30 days? (3) Do you think you might smoke a cigarette any time during the next year? A susceptible never smoker provided responses other than ‘definitely not’ to any of the three susceptibility questions. ⁎A non-susceptible nonsmoker either answered ‘no’ to question 1 and ‘definitely not’ to 2 & 3, or only answered ‘definitely not’ to questions 2 & 3 of the following: 1) “Do you think you will try a cigarette soon?” 2) “If one of your best friends were to offer you a cigarette, would you smoke it?” and 3) “Do you think you will be smoking one year from now?” A susceptible nonsmoker answered ‘yes’ to the first question and anything other than ‘definitely not’ to questions 2 and 3. ⁎A non-susceptible nonsmoker responded ‘definitely not’ to both of the following: 1) “If one of your best friends offered you a cigarette, would you smoke it?” and 2) “At any time during the next 12 months, do you think that you will smoke a cigarette?” A susceptible nonsmoker responded either “definitely yes”, “probably yes”, or “probably not” to the two questions. ⁎⁎ These are auxiliary terms created to supplement the operational definitions (i.e., they were not provided by the authors of the paper; although the authors of the paper provided operational definitions for classification purposes). NR = Not reproducible. a Non italicized smoking status categories are the main categories used in the study, whereas italicized categories represent secondary categories used in the study. b Pearson's C statistic is used to measure the association between the literature based smoking status categories and the smoking identities selected by youth in our database. c These associations should be interpreted with caution due to missing data that can affect the comparison of these categories with other smoking status categories.

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which researchers define youth smoking and advance a consensus in the use of formative taxonomies and classifications of youth smoking behavior.

Appendix (continued) A (continued) Search 8

Acknowledgements

9

This research was supported, in part, by a Canadian Institutes of Health Research (CIHR) operating grant (grant # 62980). Dr. C.T.C. Okoli was supported by a CIHR Strategic Training Program in Tobacco Research Postdoctoral Fellowship through the Integrated Mentor Program in Addictions Research Training (IMPART) and a Michael Smith Foundation for Health Research (MSFHR), NEXUS Research Unit Post-doctoral Traineeship. Dr. P. A. Ratner is a Senior Scholar funded by the MSFHR. Dr R. Haines was supported by a CIHR Strategic Training Program in Tobacco Research Postdoctoral Fellowship through the IMPART program. K. Sullivan was supported by Social Science and Health Research Council (SSHRC) Doctoral Fellowship and a CIHR Strategic Training Program in Tobacco Research doctoral traineeship through the IMPART program. Dr. S.E. Guo is an assistant professor at the University of Victoria. Dr. J. L. Johnson was supported by a CIHR Investigator Award.

991

10 11 12 13

14 #1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR #11 OR #12 OR #13 OR #14

Terms OR ex-smoker AND youth social smoker AND adolescents OR social smoker AND youth occasional smoker AND adolescents OR occasional smoker AND youth irregular smoker AND adolescents OR Irregular smoker AND youth regular smoker AND adolescents OR regular smoker AND youth heavy smoker AND adolescents OR heavy smoker AND youth experimental smoker AND adolescents OR experimental smoker AND youth experimenters AND adolescents OR experimenters AND youth

Results 61 11

0 35 16 12

328

References Appendix A

PUBMED search results (limits: adolescents 13–18, Jan 1 2002–Nov 30 2007, English Language). Search

Terms

1

current[All Fields] AND smoker [All Fields] nonsmoker[All Fields] OR non-smoker [All Fields] former[All Fields] AND smoker [All Fields] (EX[All Fields] AND SMOKER [All Fields]) OR EX-SMOKER[All Fields] SOCIAL[All Fields] AND SMOKER[All Fields] occasional[All Fields] AND smoker [All Fields] irregular[All Fields] AND smoker [All Fields] regular[All Fields] AND smoker [All Fields] heavy[All Fields] AND smoker [All Fields] experimental[All Fields] AND smoker [All Fields] experimenters[All Fields] AND (“smoking”[MeSH Terms] OR smoking [Text Word])

2 3 4 5 6 7 8 9 10 11

Results

#1 OR #2 OR #3 OR #4 OR #5 OR #6 OR #7 OR #8 OR #9 OR #10 OR #11

88 77 18 20 72 7 1 26 16 11 22

236

Science Direct search (limits: N2001 and pub-date b 2008). Search

Terms

1

current smoker AND adolescents OR current smoker AND youth nonsmokers AND adolescents OR nonsmokers AND youth non-smoker AND adolescents OR non-smoker AND youth none smokers AND adolescents OR none smokers AND youth former smoker AND adolescents OR former smokers AND youth ex smoker AND adolescents OR ex smoker AND youth ex-smoker AND adolescents

2 3 4 5 6 7

Results 75 63 52 3 9 11 11

(continued on next page)

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