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Introduction: In adults, chronic exposure to air pollution is associated with elevated blood pressure, but few studies have examined this relationship in youth. We investigated the association between annual ambient concentrations of air pollutants (fine particulate matter [PM2.5] and nitrogen dioxide [NO2 ]) and systolic blood pressure (SBP) among adolescents in Montréal, Canada. Methods: Participants were students aged 15 to 17 years who provided SBP and residential postal code data in 2004/05 through their enrolment in the Nicotine Dependence in Teens study. Annual estimates for 2004 of residential exposure to NO2 and PM2.5 were provided by the Canadian Urban Environmental Health Research Consortium and linked to participants’ residential postal code. Elevated SBP was defined as SBP ≥ 90th percentile adjusted for age, sex and height. Logistic regression was used to estimate odds ratios and 95% confidence intervals (CIs) for each pollutant with respect to elevated SBP, adjusted for relevant confounders. Results: The sample consisted of 508 adolescents (mean age: 16.9, 46% male); 4% had elevated SBP. Although estimates were not statistically significant, there were generally modest positive associations between pollutant levels and SBP. The adjusted prevalence odds ratio of elevated SBP was 1.33 (95% CI: 0.64, 3.05) for every interquartile range (IQR) increase in residential PM2.5 levels (2.1µg/m³ ). Similarly, the adjusted prevalence odds ratio of elevated SBP was 1.17 (95% CI: 0.47, 2.70) for every IQR increase in residential NO2 levels (10.2 ppb). [ABSTRACT FROM AUTHOR]

Introduction: We examined whether factors identified as associated with cannabis use at age 14 to 16 years are also associated with ever use at age 12. Methods: Participants in the AdoQuest study (n = 1852) were recruited in 2005 from among Grade 5 students in 29 French-language elementary schools in Montréal, Canada. Self-report data were collected from participants in Grade 5 (spring 2005) and 6 (fall 2005 and spring 2006) and from parents/guardians in 2006/07. Inclusion in the analytic sample (n = 1076; mean age [SD] = 10.7 [0.5]) required data from participant and parental questionnaires and data on cannabis use in Grade 6 (mean age [SD] = 11.7 [0.4]). We estimated associations between ever use at age 12 with 33 potential correlates, separately in unadjusted and adjusted logistic regression models. Results: Fifty-three participants (4.9%) reported ever use at age 12. Factors associated with higher odds of ever use included older age, identifying as male, lower household income, more weekly spending money, ever tried cigarettes or other tobacco products, ever drank alcohol or binge drank, ever gambled, friends or siblings smoke cigarettes, greater nicotine dependence, higher depressive symptoms and greater impulsivity. Protective factors included higher levels of parental/guardian monitoring and greater self-esteem and school connectedness. Conclusions: Factors associated with cannabis use at later ages are also associated with ever use at age 12. Our findings suggest that surveillance for and interventions to prevent cannabis use are warranted before age 12. [ABSTRACT FROM AUTHOR]

Purpose: The association between stressful life events and depressive symptoms is well-established, but the role of coping style in this association is less clear. We examined whether problem-focused, emotion-focused or avoidant coping style mediated and/or moderated the association in young adults. Methods: Data were drawn from a 20-year longitudinal study that included 1294 students' age 12–13 years recruited in 1999–2000 from ten high schools in Montreal, Canada. Herein we report an analysis that included 782 participants aged 24 years on average with data on covariates collected at age 20. Using VanderWeele's four-way decomposition approach, the total effect of stressful life events on depressive symptoms considering coping styles was decomposed into four components: moderation only, mediation only, mediated interaction, no mediation or moderation. Results: We observed mediation only by emotion-focused coping ( β ^ (95%CI) = 0.15(0.04, 0.24)) suggestive that individuals who experienced more stressful life events also reported greater use of emotion-focused coping and higher levels of depressive symptoms. We found moderation only by problem-focused coping ( β ^ (95%CI) = − 1.51(− 2.40, − 0.53)) and by emotion-focused coping ( β ^ (95%CI) = 1.16(0.57, 1.69). These results suggest that individuals reporting more problem-focused coping experienced fewer depressive symptoms after exposure to stressful life events; those reporting more emotion-focused coping experienced more depressive symptoms. Avoidant coping did not mediate or moderate the association between stressful life events and depressive symptoms. Conclusion: Interventions that aim to reduce depressive symptoms in young adults who experience stressful life events may need to reinforce problem-focused coping and minimize emotion-focused coping strategies. [ABSTRACT FROM AUTHOR]

Introduction: Most studies modeling adolescent cigarette smoking trajectories use age as the time axis, possibly obscuring depiction of the natural course of cigarette smoking. We used a simulated example and real data to contrast smoking trajectories obtained from models that used time since smoking onset or calendar time (age) as the time axis.Methods: Data were drawn from a longitudinal investigation of 1293 grade 7 students (mean age 12.8 years) recruited from 10 high schools in Montreal, Canada in 1999-2000, who were followed into young adulthood. Cigarette consumption was measured every 3 months during high school, and again at mean ages 20.4 and 24.0. Analyses using time since onset of smoking as the time metric was restricted to 307 incident smokers; analysis using calendar time included 645 prevalent and incident smokers. Smoking status and nicotine dependence (ND) were assessed at mean ages 20.4 and 24.0. Simulated data mimicked the real study during high school.Results: Use of different time metrics resulted in different numbers and shapes of trajectories in the simulated and real datasets. Participants in the calendar time analyses reported more ND in young adulthood, reflecting inclusion of 388 prevalent smokers who had smoked for longer durations.Conclusions: Choosing the right time metric for trajectory analysis should be balanced against research intent. Trajectory analyses using the time since onset metric depict the natural course of smoking in incident smokers. Those using calendar time offer a snapshot of smoking across ages during a given time period.Implications: This study uses simulated and real data to show that trajectory analyses of cigarette smoking that use calendar time (e.g., age) versus time since onset as the time axis metric tell a different story. Trajectory analyses using the time since onset metric depict the natural course of smoking in incident smokers. Those using calendar time offer a snapshot of smoking across ages during a given time period. Choosing the right time metric should be balanced against research intent. [ABSTRACT FROM AUTHOR]

Objective: Body mass index (BMI) is used to identify trajectories of adiposity in youth, but it does not distinguish fat‐ from fat‐free‐mass. There are other inexpensive measures of adiposity which might better capture fat‐mass in youth The objective of this study is to examine differences between sex‐specific trajectories of BMI and other adiposity indicators (subscapular and triceps skinfold thickness, waist circumference, waist‐to‐height ratio) which may better capture fat‐mass in youth. Methods: Data come from four cycles of a longitudinal cohort of 1293 students in Montréal, Canada at ages 12, 15, 17 and 24. Group‐based trajectory models identified sex‐specific adiposity trajectories among participants with data in ≥3 cycles (n = 417 males; n = 445 females). Results: There were six trajectory groups in males and females for all five indicators, except for waist circumference (seven) in both sexes and triceps skinfold thickness (four) and waist‐to‐height ratio (five) in females. Most trajectories indicated linear increases; only the skinfold thickness indicators identified a decreasing trajectory. While all indicators identified a trajectory with high levels of adiposity, they differed in the number and relative size of trajectories pertaining to individuals in lower half of the adiposity distribution. Conclusion: BMI is a satisfactory indicator of adiposity in youth if the aim of the trajectory analysis is to identify youth with excess adiposity, a known risk factor for cardiometabolic outcomes in adulthood. [ABSTRACT FROM AUTHOR]

Introduction: Few interventions target adolescent cigarette smokers to prevent escalation in cigarette use or promote cessation, in part because little is known about co-developing smoking and nicotine dependence (ND). Our objectives were to: (1) estimate developmental trajectories of ND/cravings, withdrawal symptoms, the modified Fagerström Tolerance Questionnaire (mFTQ) and ICD-10 tobacco dependence in incident adolescent smokers; (2) describe concordance in number and shapes of trajectories across the four ND indicators; and (3) classify participants in each ND trajectory according to cigarette smoking trajectories.Methods: Data were drawn from an ongoing longitudinal investigation of 1294 grade 7 students recruited in 1999-2000 in 10 Montreal-area high schools. Group-based joint trajectory models were used to identify distinct subgroups defined by the four ND indicators, in 307 incident smokers.Results: The optimal trajectory model included five groups for ND/craving and four groups for each of withdrawal symptoms, the mFTQ and ICD-10 tobacco dependence. The four ND indicators showed similar developmental patterns and classification into smoking trajectory groups, although some discordance was observed. Smokers in the low-level decreaser group and stable low consumers who exhibited high ND were younger than those in the cigarette-low ND trajectory groups. Moderate or rapid escalators who exhibited no/low ND were less likely to have university-educated mothers and more likely to have parents who smoke.Conclusions: Trajectories were similar across ND indicators, and generally reflected cigarette smoking trajectory shapes. Novice smokers may need education to become self-aware of developing ND symptoms, as well as to learn about alternative courses of action once ND symptoms manifest.Implications: Trajectories of cigarette smoking and ND symptoms have rarely been investigated concurrently. This study provides evidence of high concordance across four distinct ND indicators in the proportion of participants with no/low-level dependence, and with high or increasing ND. Moreover, the development of cigarette smoking is concordant with ND symptom development. Interventions to prevent escalation and promote cessation should target adolescents before first puff to increase self-awareness of developing ND symptoms, as well as to learn about alternative courses of action once ND symptoms are experienced. [ABSTRACT FROM AUTHOR]

Background: Despite the benefits of physical activity, many Canadian adolescents are inactive and rates of inactivity increase with age. Few studies describe the pattern of change in physical activity as a function of age during adolescence. Methods: Data were drawn from the Nicotine Dependence in Teens Study. The analytic sample included 1206 adolescents who completed a 7-day physical activity recall up to 4 times per year over 5 years. Individual growth models, analyzed using multilevel models for change, were developed separately by sex controlling for season. Results: Physical activity levels through adolescence were best described by a cubic function. Levels increased from age 12 to a peak at approximately age 13.5, decreased to age 16.5, and increased again to age 17. Activity participation was highest in the spring and lowest during fall and winter. Substantial within- and between-subject heterogeneity in the trajectories was evident. Conclusion: Adolescent physical activity follows a complex, curvilinear pattern in both males and females, with considerable variation within- and between-persons. [ABSTRACT FROM AUTHOR]

Objectives: Daily cannabis use can portend problematic use or dependence. We aimed to identify early risk factors for daily cannabis use in young adults.Methods: Data were available in a longitudinal investigation of 1294 grade 7 students age 12 to 13 years at inception recruited in 10 secondary schools in Montreal, Canada, in 1999. Data on daily cannabis use were collected in mailed self-report questionnaires from 878 participants (67.9% of 1294) at age 20. The associations between each of 23 potential risk factors measured in grade 7 and daily cannabis use at age 20 were modeled using logistic regression.Results: At age 20, 44% of participants reported past-year cannabis use; 10% reported daily use. Older age; male sex; higher levels of family stress and other stress; use of alcohol, cigarettes, and other tobacco products; parent(s), sibling(s), and friend(s) smoke cigarettes; higher body mass index; higher impulsivity and novelty seeking; and lower self-esteem increased the odds of daily cannabis use.Conclusions: Children at risk of daily cannabis use as young adults can be identified early. They may benefit from early intervention to prevent problematic cannabis use. [ABSTRACT FROM AUTHOR]

Introduction: Recent studies evidenced that adolescent never-smokers exposed to secondhand tobacco smoke (SHS) endorsed nicotine dependence symptoms. Other studies showed that SHS exposure measured with biomarkers among never-smokers independently predicted withdrawal sensations and prospective smoking initiation. The aim of the present study was to replicate and extend these findings by investigating whether social and pharmacological measures of SHS exposure predicted precursors to smoking among never-smoking adolescents. Methods: Participants included 327 never-smokers aged 11–15 years attending sixth or seventh grade in French language schools in Montréal, Canada. They completed self-report questionnaires measuring their smoking status, social smoke exposure (number of smokers in their environment and number of situations where SHS exposure occurs), and precursors to smoking initiation (smoking expectancies, perceived nicotine dependence, and smoking susceptibility). Each participant provided a saliva sample from which cotinine biomarkers were derived to measure pharmacological exposure to SHS. Results: When predictors were modeled individually, number of smokers predicted perceived nicotine dependence (p ≤ .05), smoking susceptibility (p ≤ .001), and expected benefits (p ≤ .05), whereas number of situations predicted smoking susceptibility (p ≤ .01). When predictors were modeled simultaneously, number of smokers predicted perceived nicotine dependence (p ≤ .01), smoking susceptibility (p ≤ .01), and expected benefits (p ≤ .05). Conclusions: Social smoke exposure was a predictor for smoking precursors. Pharmacological exposure to SHS did not predict smoking precursors, which may be partly attributable to the low cotinine values observed in our sample. Suggestions for improved pharmacological measurement of SHS and implications for public health are discussed. [ABSTRACT FROM AUTHOR]

Objectives: To describe the prevalence and co-occurrence of lifestyle risk factors for chronic disease by family origin.Design: Cross-sectional analysis.Setting: Multiethnic, low-income, urban neighborhoods in Montreal, Canada.Participants: 2033 adults (42.2% male), mean age 39.7 (standard deviation 6.4) yearsOutcome Measures: Smoking, level of physical activity, dietary habits, body mass index.Methods: Subjects completed self-report questionnaires on sociodemographic characteristics, height, weight, and lifestyle behaviors. We tested family origin (based on language first learned in childhood and country of birth) as an independent correlate of co-occurrence (having at least two lifestyle risk factors) in multivariate logistic regression analyses.Results: The prevalence of smoking and poor diet was highest among participants of French Canadian family origin. Although physical inactivity was uniformly high across family origins, it was highest among participants of Portuguese, Italian, and Haitian family origin. Obesity was highest among Europeans. The prevalence of smoking was lowest among Haitians; poor diet was lowest among South Asians; and physical inactivity was lowest among Eastern Europeans. Obesity was lowest among Asians, with the exception that 55.9% of South Asians were overweight or obese. Relative to French Canadians, adults in all other family-origin groups had a lower risk of co-occurrence of lifestyle risk factors. Adults of Asian family origin had the lowest prevalence of co-occurrence of lifestyle risk factors.Conclusion: Variation in the distribution of lifestyle risk factors may explain in part differences in chronic disease morbidity and mortality across ethnic groups. Prevention programs should take differential distribution of lifestyle risk factors by ethnicity into account. [ABSTRACT FROM AUTHOR]

Background: Primary care physicians are potentially important sources of interventions aimed at preventing youth smoking. Yet recent surveys suggest that physician smoking prevention practices are less than optimal. Objectives: To document prevention counseling practices and to identify correlates of these activities in a random sample of general practitioners in Montreal, Quebec. Methods: A cross-sectional mail survey. Results: Of 440 eligible general practitioners (GPs), 337 (77%) completed the questionnaire. General practitioners were more likely to ascertain the smoking status of adolescents (70.9%) than preadolescents (35.7%). Although about half of the GPs offered advice to prevent smoking onset in young adults (48.6%) and adolescents (48.3%), fewer did so for preadolescents (34.4%); only 12.1% advised parents to discuss smoking onset with their children. Correlates of ascertaining smoking status included female sex (odds ratio [OR], 1.90; 95% confidence interval [CI], 1.07-3.41), lower proportion of walk-in patients (OR, 2.73; 95% CI, 1.31-5.80), awareness of the "stage of behavior change'' model (OR, 2.17; 95% CI, 1.18-4.04), and higher self-efficacy (OR, 4.12, 95% CI, 2.00-8.69). Correlates of provision of prevention advice included more hours spent in direct patient care (OR, 1.93; 95% CI, 1.13-3.34), favorable beliefs and attitudes (OR, 1.73; 95% CI, 1.06-2.83), and higher self-efficacy (OR, 4.32; 95% CI, 2.25-8.44). Conclusions: Our results point to the need for renewed efforts to enhance preventive efforts in primary care settings. Intervention programs for GPs should emphasize overcoming unfavorable beliefs and attitudes and low self-efficacy. Future research should evaluate the effect of brief prevention counseling adapted to increasingly busy practices. [ABSTRACT FROM AUTHOR]

Presents information about Physicians Taking Action Against Smoking, an intervention program to optimize smoking cessation counselling by Montreal general practitioners (GP). Program description; Results of monitoring the smoking cessation counselling practices of GPs; Interpretation; Conclusion that an integrated, theory-based program to prove physicians' counselling practices could be a key component in a comprehensive strategy to reduce tobacco consumption.

Longitudinal studies are needed to increase understanding of the causes of childhood obesity. To identify 1- and 2-year predictors of excess weight gain among preadolescents, the authors conducted a prospective cohort study of fourth- and fifth-grade students in 16 elementary schools located in multiethnic, low-income neighborhoods in Montreal, Quebec, Canada, that were participating in the evaluation of a school-based heart health promotion program. Subjects included 2,318 children aged 9–12 years with baseline and 1-year follow-up data and 633 children aged 9–11 years with baseline and 2-year follow-up data. One-year predictors of highest decile of change in body mass index (BMI) identified in logistic regression analyses included baseline BMI of 90th percentile or more (odds ratio (OR) = 2.66, 95% confidence interval: 1.80, 3.94) in boys and baseline BMI of 90th percentile or more (OR = 2.34, 95% confidence interval: 1.46, 3.76), no sports outside school (OR = 1.90, 95% confidence interval: 1.18, 3.06), and playing video games everyday (OR = 2.48, 95% confidence interval: 1.04, 5.92) in girls. Two-year predictors included baseline BMI of 90th percentile or more (OR = 3.26, 95% confidence interval: 1.52, 7.01), no sports outside school (OR = 2.14, 95% confidence interval: 0.96, 4.77), and least active (OR = 2.18, 95% confidence interval: 1.01, 4.71) in boys; only baseline BMI of 90th percentile or more (OR = 2.22, 95% confidence interval: 1.02, 4.81) was significant in girls. Results suggest the need for interventions to promote increased physical activity in children. Am J Epidemiol 2000;152:739–46. [ABSTRACT FROM PUBLISHER]

To investigate the association between the neighborhood built environment and trajectories of body mass index (BMI) in youth. Data were collected in a prospective study of 1293 adolescents in Montreal. Built environment variables were obtained from public databases for road networks, land use, and the Canadian Census. Anthropometric data were collected when participants were ages 12.5, 15 and 17 years. We undertook hierarchical cluster analysis to identify contrasting neighborhood types based on features of the built environment (e.g., vegetation, population density, walkability). Associations between neighborhood type and trajectories of BMI z-score (BMIz) were estimated using multivariable linear mixed regression analyses, stratified by sex. We identified three neighborhood types: Urban , Suburban , and Village. In contrast to the Urban type, the Suburban type was characterized by more vegetation, few services and low population density. Village and Suburban types were similar, but the former had greater land use diversity, population density with more parks and a denser food environment. Among girls, living in Urban types was associated with decreasing BMIz trajectories. Living in Village types was associated with increasing BMIz trajectories. No associations were observed among boys. Neighborhoods characterized by greater opportunities for active living appear to be less obesogenic, particularly among girls. • Three neighborhood types were identified based on features of the built environment. • Neighborhoods had varying levels of vegetation, services and walkability. • Greater walkability and variety of services led to decreasing BMI in girls. [ABSTRACT FROM AUTHOR]

Objectives. This study evaluated the impact of a 4-year, community-based cardiovascular disease prevention program among adults aged 18 to 65 years living in St-Henri, a low-income, inner-city neighborhood in Montreal, Quebec. Methods. Awareness of and participation in the program were monitored in 3 independent sample telephone surveys. Self-reported behaviors were compared in St-Henri and a nearby comparison community before and after program implementation in both a 3-year repeat independent sample survey and a 5-year longitudinal cohort telephone survey. Results. Awareness of the program reached 37.4%, but participation was low (2%-3%). There were no secular declines in smoking or high-fat diet; physical inactivity increased in both communities. There were no statistically significant program effects detected in the independent sample surveys, although physical inactivity increased more in the comparison community than in St-Henri. In the longitudinal cohort sample, there was a small, statistically significant increase favoring St-Henri in frequency of cholesterol checkups. Conclusions. Despite careful adaptation of the program to the local social context, there were few community-wide program effects. However, several component interventions showed promise in terms of community penetration and impact. (Am d Public Health. 1999;89: 1819-1826) [ABSTRACT FROM AUTHOR]

To assess the association between childhood body fatness and epithelial ovarian cancer (EOC), and whether this association differs by type of EOC. Using data from a population-based case-control study (497 cases and 902 controls) in Montreal, Canada conducted 2011–2016, we examined the association between childhood body fatness and EOC, overall and separately for invasive vs. borderline EOCs. A figure rating scale was used to measure body fatness at ages 5 and 10. Multivariable logistic regression was used to estimate adjusted odds ratios (aORs) and 95% confidence intervals (95% CI). Quantitative bias analyses were conducted to assess the impact of exposure misclassification and non-participation. The aOR (95% CI) of overall EOC for high vs. low body fatness was 1.07 (0.85–1.34) at age 5 and 1.28 (0.98–1.68) at age 10. The associations were stronger for invasive EOC, specifically the endometrioid histological type. For borderline cancers, the aORs were below the null value with wide confidence intervals. Bias analyses did not reveal a strong influence of non-participation. Non-differential exposure misclassification may have biased aORs towards the null for invasive cancers but did not appear to have an appreciable influence on the aORs for borderline cancers. Childhood body fatness may be a risk factor for invasive EOC in later adult life. Our study highlights the potential importance of examining early life factors for a comprehensive understanding of EOC development. • Few studies have examined the link between childhood body fatness and epithelial ovarian cancer (EOC) risk. • High childhood body fatness is positively associated with invasive EOC. • Quantitative bias analyses suggested minimal distortion of the estimates by selection bias or information bias. • The findings support that early-life exposures may influence later-life risk of EOC. [ABSTRACT FROM AUTHOR]

• 52% of 244 11th grade smokers reported past-year smoking at age 31. • 30 % of < monthly & 50 % of monthly 11th grade smokers smoked at age 31. • Only 29 (12%) reported past-year abstinence consistently at ages 20, 24 and 31. • Predictors of smoking at age 31 = smoking frequency/intensity & longer time since onset. • Perceived nicotine addiction predicted past-year smoking at age 31. Quitting smoking by the mid-30 s conveys important health benefits. Yet, although many smokers attempt to quit, few succeed. Identification of the characteristics of adolescent smokers most likely to continue smoking between ages 30 and 40 could help target early cessation efforts. Our objectives in this study were to (i) describe the course of smoking in a population-based sample of high school smokers into their 20 s and 30 s, and (ii) identify distal predictors of past-year cigarette smoking at age 31. Data at ages 17 (in 11th grade), 20, 24 and 31 were drawn from a 20-year longitudinal study of students ages 12–13 at inception, from 10 high schools in Montréal, Canada. Associations between 11 smoking-related characteristics measured in 11th grade and past-year smoking at age 31 were estimated in multivariable logistic regression models. Among 244 11th grade smokers (67.4% female; 41% daily smokers), past-year smoking was reported by 71% at age 20, 68% at age 24, and 52% at age 31. Only 12% reported abstinence at ages 20, 24 and 31. Females were less likely than males to smoke at age 31. Parental smoking while the smoker was in 11th grade, use of other tobacco products, longer time since smoking onset, weekly or daily smoking, monthly cigarette consumption, and perceived nicotine addiction predicted past-year smoking at age 31. In addition to preventive interventions, cessation programs targeting novice smokers in high school as soon as they begin smoking, are warranted. [ABSTRACT FROM AUTHOR]

Background: Nicotine dependence (ND) symptoms can occur soon after first puff, so that stopping smoking becomes difficult well before 100 cigarettes lifetime is attained. Yet some surveillance systems do not monitor ND symptoms and 100-cigarettes lifetime is used in at least one surveillance system to define current smokers. To assess whether these features limit interpretation of grade-specific data in surveillance, we described smoking and ND symptoms across grade in incident vs. prevalent smokers, and in smokers according to 100-cigarettes lifetime.Methods: Data were available in an investigation of 1294 grade 7 students from 10 Montreal-area high schools followed every 3 months from grade 7 to 11. Analyses described cigarette consumption, 100-cigarette lifetime consumption, cravings, withdrawal symptoms, mFTQ nicotine dependence and ICD-10 tobacco dependence by grade among past 3-month smokers.Results: Despite low cigarette consumption, 21-30% of grade 7 smokers reported ND symptoms. This increased to 27-44% in grade 8 and remained stable thereafter despite increased cigarette consumption. In grade 7, 10% of all smokers had not attained the 100-cigarette milestone but were already dependent. In grade 8, 9, 10 and 11, these proportions were 12%, 8%, 6% and 6%, respectively.Conclusions: ND symptoms should be monitored in youth surveillance systems since they tell a different "story" than cigarettes and their appearance may represent a critical "point-of-no-return." Interventions for incident smokers are needed across grades to stop smoking before ND manifests. Without a shift in focus toward incident rather than established smokers, many children who try cigarettes will become addicted. [ABSTRACT FROM AUTHOR]