Abstract
Objectives. We sought to determine whether adolescents living in households in which smoking was banned were more likely to develop antismoking attitudes and less likely to progress to smoking compared with those living in households in which smoking was not banned.
Methods. We completed a longitudinal 4-year, 3-wave study of a representative sample of 3834 Massachusetts youths aged 12 to 17 years at baseline; 2791 (72.8%) were reinterviewed after 2 years, and 2217 (57.8%) were reinterviewed after 4 years. We used a 3-level hierarchical linear model to analyze the effect of a household ban on antismoking attitudes and smoking behaviors.
Results. The absence of a household smoking ban increased the odds that youths perceived a high prevalence of adult smoking, among both youths living with a smoker (odds ratio [OR] = 1.56; 95% confidence interval [CI] = 1.15, 2.13) and those living with nonsmokers (OR = 1.75; 95% CI = 1.29, 2.37). Among youths who lived with nonsmokers, those with no home ban were more likely to transition from nonsmoking to early experimentation (OR = 1.89; 95% CI = 1.30, 2.74) than were those with a ban.
Conclusions. Home smoking bans may promote antismoking attitudes among youths and reduce progression to smoking experimentation among youths who live with nonsmokers.
The proliferation of US smoke-free workplace policies and laws over the past decade has been accompanied by increased attention to private household smoking restrictions. The number of US households with comprehensive rules that make homes smoke free in all areas at all times has increased substantially.1 The proportion of US households with smoke-free home rules increased from 43% in 1992 to 1993 to 72% in 2003.2 Even smokers appear to be increasingly adopting such rules, particularly in homes in which they live with a nonsmoking adult.
Although smoke-free home bans are typically implemented to reduce or eliminate environmental tobacco smoke exposure in the household, these bans may have the additional benefit of reducing the initiation of smoking among youths by changing norms about the prevalence and social acceptability of smoking. Very little is known about the specific effect of a household smoking ban on youth smoking behavior or on smoking-related attitudes and norms that may mediate an effect on smoking behavior. In particular, few studies have addressed the independent effect of bans on youths who live with smokers—those who are at the greatest risk for becoming smokers themselves.
Recent studies showed that strong smoking regulations in local restaurants and bars were associated with more negative attitudes among youths toward the social acceptability of smoking in restaurants and bars.3–6 Establishing household smoking bans conveys to youths living within these smoke-free home environments the message that smoking is unacceptable. Some supportive evidence, derived from cross-sectional data, indicates that a household smoking ban is associated with antismoking attitudes and norms. A recent cross-sectional study found that a household ban was associated with a lower perceived prevalence of adult smoking and more-negative attitudes about the social acceptability of smoking, 2 factors that affect the likelihood of smoking initiation.7
Several cross-sectional studies have reported that a smoking ban in the household was associated with a lower likelihood of being in an earlier stage of smoking and a lower current smoking prevalence among adolescents.8–11 Conversely, other studies found no statistically significant association between a household smoking ban and reduced adolescent smoking.12–14 Several factors may account for these conflicting results, including varying sample sizes, age groups, and smoking measures used in these cross-sectional studies.
A critical question is whether antismoking socialization occurs when parents themselves smoke. One study found that a household smoking ban was related to lower levels of smoking onset for children with nonsmoking parents but not for children with 1 or more parent who smoked.15 Another study reported that a household smoking ban was not associated with trying smoking among high school students who had 1 or more parents who were current or former smokers.16 Only 1 study reported an association between a household smoking ban and a reduced likelihood of smoking among 12th graders whose parents were smokers but not among those whose parents were nonsmokers.17 In summary, more evidence supports an association between home smoking bans and lower levels of smoking behaviors among youths who live with nonsmokers.
Current research on household smoking bans has significant limitations. First, these studies rely on cross-sectional data that limit the ability to indicate causality in the relation between home smoking bans and trajectories of attitudes and smoking. Second, most studies have focused on individual-level predictors of attitudes and smoking behaviors, despite evidence that part of the explanation lies within the community context.18 Third, few studies have investigated the unique effects of a household smoking ban among adolescents living in home environments with parental smokers compared with those living with nonsmokers.
In this study, our goal was to improve existing research by (1) using longitudinal data that followed up a cohort of youths and young adults who lived in parental homes over a 4-year period, with a total of 3 repeated observations for each participant; (2) using a multilevel model that simultaneously examined the effects of individual-level and town-level factors; and (3) investigating separately the effects of a household ban on youths who live with at least 1 smoker and youths who live with nonsmokers.
In this longitudinal 4-year, 3-wave study of a representative sample of 3834 Massachusetts youths aged 12 to 17 years at baseline (2001–2002), 2791 (72.8%) were reinterviewed after 2 years (in 2003–2004), and 2217 (57.8%) were reinterviewed after 4 years (in 2005–2006). We used a 3-level hierarchical linear model to analyze individual-level and town-level predictors of antismoking attitudes and smoking behaviors. The main predictor was a complete household smoking ban (yes vs no) assessed 2 years before measurement of the outcome. All analyses were stratified by youth report of family smoking: youths were categorized as living with a smoker if they responded that they have a parent or guardian who smokes cigarettes (1 or more smokers in household). In total, we examined 5 outcomes; the 3 attitudinal outcomes included (1) higher perceived prevalence of adult smoking in town, (2) perceived social acceptability of adult smoking in town, and (3) perceived social acceptability of youth smoking in town. The 2 behavioral outcomes included (1) the progression from nonsmoking to experimentation and (2) the transition from nonestablished to established smoking.
Between January 2001 and June 2002, the Center for Survey Research, University of Massachusetts, Boston, obtained a probability sample of 3834 Massachusetts youths, aged 12 to 17 years, by random-digit dialing. Between January 2003 and July 2004, we attempted to reinterview all youths in the baseline sample. Interviews were completed with 2791 youths, for a follow-up rate of 72.8%. Between January 2005 and July 2006, we attempted to reinterview all youths who responded to the wave-2 survey as well as those wave-1 youths who did not respond to wave 2 but for whom we had contact information. Interviews were completed with 2217 individuals (57.8% of the baseline sample). The analyses were restricted to youths who lived in parental homes, because they are primarily influenced by rules that have been established by other people.10 Of those who completed wave 2, 88.9% (2481) lived with a parent at the time of interview, and of those who completed wave 3, 73.4% (1628) lived with a parent.
At waves 1 and 2, all youths were asked the question, “Some households have rules about when and where people may smoke. When you have visitors who smoke, are they allowed to smoke inside your home?” Youths who lived in a home in which at least 1 adult smoked were asked, “Do smokers in your household smoke inside your home?” Youths were categorized as having a complete household smoking ban if they reported that visitors were not allowed to smoke inside the home and, for those who lived in a home in which at least 1 adult smoked, if they reported a ban on smoking inside the home.
Youths' perception of adult smoking prevalence in their town was based on their response to the following survey item: “About how many of the [TOWN] adults that you know smoke cigarettes?” Respondents who reported “very few” or “less than half” were classified as having a low level of perceived smoking prevalence for the adults in their town, whereas respondents who answered “about half,” “more than half,” or “almost all” were categorized as having a high level of perceived smoking prevalence for the adults in their town.
Two dichotomous measures of the perception of adult disapproval of smoking were assessed. Youth perception of adult disapproval of other adults smoking was based on the response to the following survey item: “How do most [TOWN] adults that you know feel about other adults smoking?” Youths were classified as perceiving adult smoking in general as “socially unacceptable” in their town if they responded that adults “disapprove a lot” or “disapprove a little,” or “socially acceptable” in their town if they responded that adults “don't mind.” Youth perception of adult disapproval of youths smoking was based on the response to the following item: “How do most [TOWN] adults that you know feel about teenagers smoking?” Youths were classified as perceiving youth smoking in general as “socially unacceptable” in their town if they responded that adults “disapprove a lot” or “disapprove a little” as opposed to “don't mind.”
Following Pierce et al.,19 we defined progression to established smoking as having smoked 100 or more cigarettes. This measure has been formally validated20–22 and used in previous studies.20–26 We chose to use progression to established smoking as the sentinel measure of smoking initiation because it avoids the problem of the irregularity of smoking during adolescence.22 It also avoids the problem of unreliable adolescent recall of smoking behavior during the previous 30 days by establishing a defined threshold of total lifetime cigarettes smoked to measure regular smoking behavior.
The experimentation stage of smoking was then defined as the period from trying a cigarette to becoming an established smoker. Thus, the stages of smoking initiation included (1) nonsmoking, (2) experimentation—having tried a cigarette but not smoked 100 cigarettes, and (3) established smoking—having smoked 100 or more cigarettes.
We examined the effect of the following individual-level variables: (1) age group (12–14, 15–17, and 18–21 years), (2) gender, (3) race (non-Hispanic White vs other), (4) presence of at least 1 close friend who smokes, (5) education level of household informant (college graduate or not), (6) household income (≤ $50 000 vs > $50 000), (7) completed only wave-1 and wave-3 interviews, and (8) self-reported smoking status (nonsusceptible never smoker, susceptible never smoker, puffer, experimenter, or current smoker).
Never smokers were defined as youths who had never puffed on a cigarette, puffers as those who had puffed but not smoked a whole cigarette, experimenters as those who had smoked at least 1 whole cigarette but none within the past 30 days, and current smokers as those who had smoked at least 1 cigarette, including 1 or more within the past 30 days. Never smokers were further classified as either susceptible or not susceptible to smoking on the basis of whether they indicated a firm commitment not to smoke in the future.19,22,24,27,28
In each attitudinal analysis, we controlled for attitudes at baseline of each transition period.
We examined the effect of the following town-level variables (included as continuous variables except when noted): (1) the percentage of each town's voters who voted “yes” on Question 1, a 1992 ballot initiative that increased the cigarette tax and created a statewide tobacco control program, (2) the percentage of White residents in each town, and (3) the percentage of youth (younger than 18 years) residents in each town. The percentage “yes” vote on Question 1 served as a measure of the baseline level of antismoking sentiment in each town before the proliferation of local restaurant smoking regulations, which has been found to correlate with the level of education in the town.29 All town-level variables were obtained from the 2000 US Census, except for the data regarding the Question 1 vote, which was obtained from the Division of Elections within the Massachusetts Office of the Secretary of State.29,30
This data set had clustering at 2 levels. First, observations were clustered within individual respondents. Each respondent could contribute up to 2 observations in the data set. Second, respondents were clustered within towns. Because observations among individuals and among respondents from the same town may be more similar than observations across respondents or across respondents from different towns, we used a multilevel (hierarchical) logistic regression model to examine the relation between absence of a household smoking ban at baseline and the study outcomes. This procedure accounts for correlation of data within individuals and within town “clusters,” reducing the probability of a type-I error that could be introduced if this correlation were ignored.31,32
All town-level variables were time-independent and assessed at the start of the study (modeled at level 3). Time-independent individual-level covariates (entered at level 2) were gender, race, informant education, and household income. The following individual-level covariates could change from survey to survey and were modeled at level 1: the presence of a household smoking ban, age group, presence of a close friend who smokes, and absence of a household smoking ban at baseline. All analyses were stratified by the time-varying covariate of living with at least 1 smoker in the household.
For the baseline sample, survey weights were computed that adjusted for the number of telephones per household and hence for the probability of selection. We made adjustments to the baseline weights with a raking procedure to correct for biased attrition. All analyses were conducted with 2-sided tests and a significance level of .05. Analyses were conducted with HLM 6.0 (Scientific Software International Inc, Lincolnwood, IL).
Our study sample consisted of 2593 unique individuals who reported a smoking ban in their household and lived with a parent, contributing a total of 3949 observations. Of the 3949 observations, 1396 (35.4%) were from youths who lived with at least 1 smoker in the household, and 2553 (64.6%) were from those who lived with nonsmokers. Of the 1396 observations from youths who lived with a smoker, 51.9% reported a complete household smoking ban; of the total 2553 observations from youths who lived with nonsmokers, 89.2% reported a complete household smoking ban (Table 1).
TABLE 1 Baseline Characteristics of Cohort and Presence of a Complete Smoking Ban in Household, by Individual and Contextual Variables Among Youths Living With Smokers or Those Living With Nonsmokers: Massachusetts, 2001–2006
| Lived With Smoker | Lived Only With Nonsmokers | |||
| Household Smoking Ban | No Household Smoking Ban | Household Smoking Ban | No Household Smoking Ban | |
| Total, no. (%) | 724 (100) | 672 (100) | 2276 (100) | 277 (100) |
| Attitudinal outcome variables | ||||
| Perceived prevalence of adult smoking in town, no. (%) | ||||
| Low (fewer than half) | 391 (54.0) | 239 (36.0) | 1703 (74.9) | 183 (65.5) |
| High (half or more) | 329 (46.0) | 425 (64.0) | 566 (25.1) | 92 (34.5) |
| Social acceptability of smoking by adults in town, no. (%) | ||||
| Unacceptable | 410 (54.5) | 271 (42.1) | 1646 (73.2) | 148 (53.7) |
| Acceptable | 311 (45.6) | 395 (57.9) | 615 (26.8) | 129 (46.3) |
| Social acceptability of smoking by youths in town, no. (%) | ||||
| Unacceptable | 672 (92.9) | 599 (90.0) | 2177 (96.1) | 257 (93.3) |
| Acceptable | 49 (7.1) | 66 (10.0) | 91 (3.9) | 20 (6.7) |
| Behavioral outcome variables | ||||
| Progression to established smoking, no. (%) | ||||
| No | 578 (87.5) | 490 (85.8) | 2053 (93.3) | 233 (91.3) |
| Yes | 81 (12.5) | 84 (14.2) | 147 (6.7) | 20 (6.7) |
| Progression from nonsmoking to experimental smoking, no. (%) | ||||
| No | 434 (77.9) | 369 (76.8) | 1722 (84.9) | 175 (78.9) |
| Yes | 122 (22.1) | 114 (23.2) | 299 (15.1) | 47 (21.1) |
| Individual-level time-varying covariates (level 1) | ||||
| Age group, y, no. (%) | ||||
| 12–14 | 294 (38.9) | 274 (40.5) | 936 (41.3) | 116 (40.2) |
| 15–17 | 373 (52.8) | 353 (52.7) | 1196 (52.0) | 148 (55.0) |
| 18–21 | 57 (8.3) | 45 (6.8) | 144 (6.7) | 13 (4.8) |
| Baseline smoking status, no. (%) | ||||
| Nonsusceptible never smoker | 203 (28.7) | 203 (31.1) | 956 (42.0) | 104 (38.0) |
| Susceptible never smoker | 251 (33.8) | 183 (27.5) | 882 (39.1) | 98 (35.5) |
| Puffed | 102 (13.9) | 97 (13.4) | 184 (8.3) | 20 (7.2) |
| Smoked whole cigarette | 79 (10.8) | 72 (11.1) | 147 (6.1) | 28 (9.6) |
| Smoked in past 30 d | 89 (12.8) | 117 (16.9) | 107 (4.5) | 27 (9.7) |
| Presence of close friend who smokes, no. (%) | ||||
| No | 428 (59.0) | 354 (53.4) | 1680 (74.2) | 196 (70.5) |
| Yes | 295 (41.0) | 318 (46.6) | 595 (25.8) | 80 (29.5) |
| Participated in 4-y follow-up (wave 1 to wave 3), no. (%) | ||||
| No | 700 (96.7) | 640 (95.6) | 2221 (97.7) | 266 (96.0) |
| Yes | 24 (3.3) | 32 (4.4) | 55 (2.3) | 11 (4.0) |
| Individual-level covariates (level 2) | ||||
| Gender | ||||
| Boy | 370 (50.9) | 327 (50.3) | 1173 (51.5) | 164 (59.6) |
| Girl | 354 (49.1) | 345 (49.7) | 1103 (48.5) | 113 (40.4) |
| Race/ethnicity | ||||
| Non-Hispanic White | 570 (79.8) | 555 (82.7) | 1862 (82.3) | 244 (88.3) |
| Other | 153 (20.2) | 110 (17.3) | 397 (17.8) | 31 (11.8) |
| Household income, $, no. (%) | ||||
| ≤ 50 000 | 222 (37.9) | 246 (44.7) | 357 (18.7) | 55 (23.6) |
| > 50 000 | 343 (62.1) | 297 (55.3) | 1532 (81.3) | 189 (76.4) |
| Informant education, no. (%) | ||||
| Not college graduate | 491 (68.1) | 476 (73.0) | 1008 (45.0) | 160 (58.3) |
| College graduate | 219 (31.9) | 175 (27.0) | 1234 (55.0) | 113 (41.8) |
| Town-level covariates (level 3) | ||||
| “Yes” vote on Question 1,a mean (%) | 724 (49.6) | 672 (47.9) | 2276 (51.9) | 277 (49.9) |
| White residents, mean (%) | 724 (88.0) | 672 (86.6) | 2276 (88.4) | 277 (89.2) |
| Residents who are youths, mean (%) | 724 (24.7) | 672 (24.4) | 2276 (24.7) | 277 (24.7) |
Note. Table entries are weighted percentages.
a Question 1 was a 1992 ballot initiative that increased the cigarette tax and created a statewide tobacco control program.
For the multivariate analyses of the attitudinal outcomes, our study sample consisted of 942 unique participants (contributing a total of 1394 observations) who lived with a smoker and 1728 unique participants (contributing a total of 2634 observations) who did not live with a smoker.
Youths living in households that lacked a complete household smoking ban were more likely to perceive a high prevalence of adult smoking in their town compared with youths who lived in households with a complete smoking ban (Table 2). The relation existed both for youths who lived with a smoker (odds ratio [OR] = 1.56; 95% confidence interval [CI] = 1.15, 2.13) and for youths who lived with nonsmokers (OR = 1.75; 95% CI = 1.29, 2.37).
TABLE 2 Adjusted Odds Ratios (ORs) for Perceived Smoking Prevalence and Acceptability of Smoking Among Youths Living With a Smoker and Those Living With Nonsmokers: Massachusetts, 2001–2006
| Higher Perceived Prevalence of Adult Smoking in Towna | Social Acceptability of Smoking by Adults in Townb | Social Acceptability of Smoking by Youths in Townc | ||||
| Lived With Smoker, OR (95% CI) | Lived With Nonsmokers, OR (95% CI) | Lived With Smoker, OR (95% CI) | Lived With Nonsmokers, OR (95% CI) | Lived With Smoker, OR (95% CI) | Lived With Nonsmokers, OR (95% CI) | |
| Main time-varying predictor variable (level 1) | ||||||
| Presence of a complete smoking ban in household | ||||||
| Yes (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| No | 1.56* (1.15, 2.13) | 1.75* (1.29, 2.37) | 1.55* (1.21, 1.99) | 1.53* (1.26, 2.22) | 1.66 (0.93, 2.98) | 1.04 (0.58, 1.89) |
| Individual-level time-varying covariates (level 1) | ||||||
| Age group, y | ||||||
| 12–14 (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| 15–17 | 0.76** (0.59, 0.99) | 0.93 (0.74, 1.18) | 0.93 (0.71, 1.23) | 1.09 (0.88, 1.35) | 1.59** (0.97, 2.60) | 2.20* (1.40, 3.48) |
| 18–21 | 0.65 (0.40, 1.05) | 0.66 (0.41, 1.09) | 0.97 (0.59, 1.60) | 0.86 (0.76, 1.73) | 0.81 (0.37, 1.92) | 0.82 (0.45, 2.56) |
| Self-reported baseline smoking status | ||||||
| Nonsusceptible never smoker (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Susceptible never smoker | 0.92 (0.68, 1.26) | 0.92 (0.74, 1.15) | 0.86 (0.61, 1.21) | 1.12 (0.89, 1.42) | 0.84 (0.42, 1.68) | 0.75 (0.42, 1.33) |
| Puffed | 1.02 (0.60, 1.75) | 1.04 (0.72, 1.51) | 1.29 (0.88, 1.91) | 1.34 (0.84, 2.15) | 1.37 (0.63, 2.98) | 0.65 (0.25, 1.67) |
| Smoked whole cigarette | 0.91 (0.57, 1.47) | 1.53 (0.98, 2.41) | 1.15 (0.73, 1.80) | 1.04 (0.67, 1.63) | 2.21 (0.99, 4.94) | 0.87 (0.35, 2.18) |
| Smoked in past 30 d | 1.43 (0.84, 2.45) | 1.47 (0.73, 2.96) | 1.45 (0.85, 2.48) | 1.54 (0.99, 2.38) | 1.86 (0.88, 3.93) | 1.64 (0.72, 3.74) |
| Presence of close friend who smokes | ||||||
| No (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 1.63* (1.15, 2.30) | 1.06 (0.79, 1.42) | 1.25 (0.92, 1.69) | 1.44* (1.13, 1.83) | 1.18 (0.70, 2.01) | 1.38 (0.84, 2.29) |
| Participated in 4-y follow-up (wave 1 to wave 3) | ||||||
| No (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 1.58 (0.73, 3.41) | 0.76 (0.40, 1.44) | 0.81 (0.43, 1.51) | 1.10 (0.55, 2.18) | 2.59** (0.89, 5.22) | 3.52* (1.53, 8.12) |
| Baseline attitude | 4.09* (2.98, 5.64) | 4.14* (3.26, 5.27) | 2.78* (2.03, 3.80) | 3.06* (2.41, 3.90) | 1.64 (0.77, 3.50) | 3.37* (1.48, 7.70) |
| Individual-level covariates (level 2) | ||||||
| Gender | ||||||
| Boy (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Girl | 0.81 (0.59, 1.10) | 0.97 (0.77, 1.23) | 0.94 (0.74, 1.20) | 0.79** (0.64, 0.97) | 0.84 (0.56, 1.25) | 0.59** (0.39, 0.91) |
| Race/ethnicity | ||||||
| Non-Hispanic White (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| Other | 1.60** (1.07, 2.38) | 1.50** (1.06, 2.11) | 0.92 (0.63, 1.35) | 1.61* (1.18, 2.20) | 1.64 (0.97, 2.76) | 1.60** (0.95, 2.72) |
| Household income, $ | ||||||
| ≤ 50 000 (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| > 50 000 | 0.61* (0.44, 0.84) | 0.62* (0.45, 0.86) | 0.88 (0.64, 1.22) | 1.10 (0.85, 1.44) | 1.16 (0.74, 1.81) | 0.87 (0.51, 1.50) |
| Informant education | ||||||
| Not college graduate (Ref) | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 |
| College graduate | 0.57* (0.41, 0.80) | 0.90 (0.68, 1.20) | 0.83 (0.60, 1.15) | 0.90 (0.72, 1.12) | 0.68 (0.43, 1.08) | 0.76 (0.48, 1.18) |
| Town-level covariates (level 3)d | ||||||
| Percentage “yes” vote on Question 1e | 0.55* (0.45, 0.67) | 0.55* (0.46, 0.64) | 0.85** (0.70, 1.03) | 0.72* (0.63, 0.81) | 0.96 (0.67, 1.35) | 0.72* (0.53, 0.96) |
| Percentage of residents who are White | 0.96 (0.86, 1.08) | 1.03 (0.93, 1.13) | 0.87** (0.78, 0.97) | 1.12** (1.01, 1.24) | 0.99 (0.84, 1.19) | 1.15 (0.92, 1.44) |
| Percentage of residents who are youths | 1.05 (0.71, 1.54) | 0.78 (0.56, 1.07) | 1.11 (0.78, 1.58) | 0.95 (0.72, 1.27) | 0.61 (0.34, 1.10) | 0.38 (0.21, 0.69) |
Note. CI = confidence interval.
a Perceived prevalence of adult smoking in town was coded as 0 (lower perception of smoking prevalence; reference category) and 1 (higher perception of smoking prevalence). Analyses were on the basis of 942 individuals living in 234 towns, contributing a total of 1391 observations for youths living with smokers, and on 1728 individuals living in 280 towns, contributing a total of 2631 observations for youths living without smokers.
b Social acceptability of smoking by adults in town was coded as 0 (perceived adult disapproval of adult smoking; reference category) and 1 (no perceived disapproval of adult smoking). Analyses were on the basis of 942 individuals living in 234 towns, contributing a total of 1394 observations for youths living with smokers, and on 1720 individuals living in 280 towns, contributing a total of 2619 observations for youths living without smokers.
c Social acceptability of smoking by youths in town was coded as 0 (perceived adult disapproval of youth smoking; reference category) and 1 (no perceived disapproval of youth smoking). Analyses on the basis of 941 individuals living in 234 towns, contributing a total of 1393 observations for youths living with smokers and analyses on the basis of 1725 individuals living in 280 towns, contributing a total of 2628 observations for youths living without smokers.
d Odds ratio associated with each 10-percentage-point increase in variable.
e Question 1 was a 1992 ballot initiative that increased the cigarette tax and created a statewide tobacco control program.
*P < .01; **P < .05.
Youths living in a household without a household smoking ban also were more likely to consider adult smoking to be socially acceptable than were youths who lived in homes with a smoking ban. The magnitude of effect of the household smoking ban was similar for youths who lived with a smoker (OR = 1.55; 95% CI = 1.21, 1.99) and for those who did not live with a smoker (OR = 1.53; 95% CI = 1.26, 2.22; Table 2).
A clinically important, although not statistically significant, effect of a complete household smoking ban was seen on the perceived social acceptability of youth smoking for youths who lived with a smoker (OR = 1.66 for absence of household smoking ban vs presence of household smoking ban; 95% CI = 0.93, 2.98). However, a complete household smoking ban had no effect on perceived youth smoking prevalence in town among youths who lived with nonsmokers (OR = 1.04; 95% CI = 0.58, 1.89; Table 2).
For analysis of the behavioral outcomes, overall progression to established smoking for youths who lived with a smoker was based on 1241 observations (wave 1 to wave 2: 738; wave 2 to wave 3: 451; wave 1 to wave 3: 52), and analysis of overall progression to established smoking for youths who did not live with a smoker was based on 2541 observations (wave 1 to wave 2: 1604; wave 2 to wave 3: 872; wave 1 to wave 3: 65). Analyses of progression from nonsmoking to experimentation for youths who lived with a smoker were based on a total of 1042 observations (wave 1 to wave 2: 631; wave 2 to wave 3: 370; wave 1 to wave 3: 41), and analyses of progression to experimentation for youths who did not live with a smoker were based on 2318 observations (wave 1 to wave 2: 1469; wave 2 to wave 3: 784; wave 1 to wave 3: 65). Sample sizes for the analyses of the transition from nonsmoking to experimentation were slightly smaller than for overall progression to established smoking because transition from nonsmoking to experimentation included only those observations for nonsmoking youths at baseline of the transition period.
The lack of a complete household smoking ban had no effect on progression to established smoking, either for youths who lived with a smoker (OR = 1.38; 95% CI = 0.92, 2.07) or for youths who lived with nonsmokers (OR = 1.08; 95% CI = 0.61, 1.93; Table 3).
TABLE 3 Adjusted Odds Ratios (ORs) for Overall Progression to Established Smoking and Transition From Nonsmoking to Experimentation Among Youths Living With a Smoker and Those Living With Nonsmokers: Massachusetts, 2001–2006
| Overall Progression to Established Smokinga | Transition From Nonsmoking to Experimentationb | |||
| Lived With Smoker, OR (95% CI) | Lived With Nonsmokers, OR (95% CI) | Lived With Smoker, OR (95% CI) | Lived With Nonsmokers, OR (95% CI) | |
| Main predictor variable (level 1) | ||||
| Presence of a complete smoking ban in household | ||||
| Yes (Ref) | 1.00 | 1.00 | 1.00 | 1.00 |
| No | 1.38 (0.92, 2.07) | 1.08 (0.61, 1.93) | 0.99 (0.73, 1.37) | 1.89* (1.30, 2.74) |
| Individual-level time-varying covariates (level 1) | ||||
| Age group, y | ||||
| 12–14 | 1.00 | 1.00 | 1.00 | 1.00 |
| 15–17 | 0.83 (0.52, 1.31) | 1.72** (1.11, 2.65) | 0.93 (0.86, 1.02) | 2.20* (1.65, 2.93) |
| 18–21 | 0.69 (0.32, 1.49) | 0.86 (0.44, 1.67) | 0.98 (0.35, 2.71) | 1.22 (0.69, 2.17) |
| Baseline smoking status | ||||
| Nonsusceptible never smoker | 1.00 | 1.00 | 1.00 | 1.00 |
| Susceptible never smoker | 1.43 (0.72, 2.85) | 1.96** (1.10, 3.48) | 0.92 (0.64, 1.30) | 1.24 (0.93, 1.67) |
| Puffed | 5.51* (2.71, 11.20) | 4.95* (2.27, 10.82) | … | … |
| Smoked whole cigarette | 12.95* (6.03, 27.77) | 19.41* (9.92, 37.99) | … | … |
| Smoked in past 30 d | 43.14* (17.35, 107.3) | 49.08* (23.20, 103.8) | … | … |
| Presence of close friend who smokes | ||||
| No | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 1.90* (1.27, 2.84) | 2.34* (1.08, 2.52) | 1.93* (1.38, 2.70) | 2.26* (1.64, 3.12) |
| 4-y follow-up period (wave 1 to wave 3) | ||||
| No | 1.00 | 1.00 | 1.00 | 1.00 |
| Yes | 3.78* (1.81, 7.85) | 4.17* (1.28, 13.59) | 1.89 (0.77, 4.65) | 2.81* (1.39, 5.67) |
| Individual-level covariates (level 2) | ||||
| Gender | ||||
| Boy (Ref) | 1.00 | 1.00 | 1.00 | 1.00 |
| Girl | 0.72 (0.48, 1.09) | 0.43* (0.29, 0.63) | 0.90 (0.65, 1.26) | 0.80 (0.63, 1.03) |
| Race/ethnicity | ||||
| Non-Hispanic White (Ref) | 1.00 | 1.00 | 1.00 | 1.00 |
| Other | 1.17 (0.62, 2.21) | 1.24 (0.69, 2.25) | 0.98 (0.61, 1.57) | 0.80 (0.47, 1.36) |
| Household income, $ | ||||
| ≤ 50 000 (Ref) | 1.00 | 1.00 | 1.00 | 1.00 |
| > 50 000 | 0.81 (0.49, 1.31) | 1.46 (0.82, 2.60) | 1.14 (0.76, 1.72) | 1.72** (1.10, 2.68) |
| Informant education | ||||
| Not college graduate (Ref) | 1.00 | 1.00 | 1.00 | 1.00 |
| College graduate | 0.79 (0.48, 1.32) | 1.08 (0.69, 1.70) | 1.18 (0.80, 1.72) | 0.95 (0.69, 1.31) |
| Town-level covariates (level 3)c | ||||
| Percentage “yes” vote on Question 1d | 0.89 (0.68, 1.17) | 1.24 (0.96, 1.59) | 1.01 (0.83, 1.24) | 1.09 (0.92, 1.30) |
| Percentage of residents who are White | 1.31* (1.08, 1.58) | 1.12 (0.88, 1.44) | 1.15 (0.96, 1.36) | 1.01 (0.88, 1.18) |
| Percentage of residents who are youths | 0.77 (0.40, 1.46) | 0.86 (0.53, 1.41) | 0.79 (0.51, 1.24) | 0.88 (0.65, 1.21) |
Note. CI = confidence interval. Ellipses indicate not applicable.
a Progression to established smoking is defined as having smoked 100 cigarettes in one's lifetime. Analyses on the basis of 858 individuals living in 229 towns, contributing a total of 1241 observations for youths living with smokers, and analyses on the basis of 1672 individuals living in 276 towns, contributing a total of 2538 observations for youths living without smokers.
b Analyses on the basis of 731 individuals living in 211 towns, contributing a total of 1042 observations for youths living with smokers, and analyses on the basis of 1538 individuals living in 268 towns, contributing a total of 2315 observations for youths living without smokers.
c Odds ratio associated with each 10-percentage-point increase in variable.
d Question 1 was a 1992 ballot initiative that increased the cigarette tax and created a statewide tobacco control program.
*P < .01; **P < .05.
Among youths who lived with nonsmokers, the absence of a complete household smoking ban increased the odds of transitioning from nonsmoking to experimentation (OR = 1.89; 95% CI = 1.30, 2.74; Table 3). However, the absence of a complete household smoking ban had no effect on the transition from nonsmoking to experimentation among those who lived with a smoker (OR = 0.99; 95% CI = 0.73, 1.37; Table 3).
To the best of our knowledge, this was the first longitudinal study to examine the effects of household smoking bans on adolescents' attitudes about the acceptability of smoking, perceptions of smoking prevalence, and likelihood of initiating smoking and to assess these relations separately among youths who lived with a smoker and those who lived with nonsmokers. We used a hierarchical, repeated measures model and found that, among youths who did and did not live with a smoker, having a home smoking ban significantly increased the odds that adolescents would have negative attitudes about the social acceptability of smoking. Having a home smoking ban reduced the odds that an adolescent would begin to experiment with cigarettes but only in homes that did not contain smokers. The presence of a household smoking ban did not reduce progression to established smoking, regardless of whether a smoker lived in the home.
These findings provide support for the hypothesis that household smoking bans provide parents with an antismoking measure that contributes to antitobacco socialization of their children.10 Even in the presence of parental smoking, prohibiting smoking in the home and clearly communicating household smoking rules may lower youths' perception of smoking prevalence and attitudes about the social acceptability of smoking.
We found no effect of a complete household smoking ban on overall progression to established smoking among adolescents. This result was unexpected, but it is consistent with Fisher et al.'s recent study findings.14 Because parental disapproval and negative parental attitudes toward smoking have been shown to decrease the likelihood of adolescent smoking, we expected a household smoking ban to reduce progression to established smoking, but it did not. We examined several alternative measures of smoking initiation (data not shown) and found no effect of household smoking bans on smoking initiation, regardless of whether a youth lived in a household with a smoker.
We did find that a household smoking ban reduced early experimentation with cigarettes but only among youths who lived with nonsmokers. Reducing experimentation with smoking may require that youths live in a home with a consistent message—nonsmoking parents who ban smoking entirely in the home. Household antismoking restrictions may be effective only when they match parental behavior.16,33
These results have several important public health policy implications. First, this study found an effect of a complete household smoking ban on perceived smoking prevalence and the perceived social acceptability of smoking above and beyond a host of individual- and town-level predictors. Thus, household smoking bans may be an effective intervention to promote antismoking attitudes, particularly among those who are at the greatest risk for exposure to smoking.
Second, these findings confirm the potential moderating effect of parental smoking. Contrary to our expectations, we found an effect of a complete household ban on the transition from nonsmoking to early experimentation only among those who lived with nonsmokers. The fact that a family member smokes may be a more important determinant of adolescent smoking than are the arrangements made to restrict smoking in the household.12
The primary potential threat to the validity of our findings is the relatively high rate of loss to follow-up in the study. Although not unusual for a telephone survey that followed up participants for 4 years, the follow-up rates of 73% at wave 2 and 58% at wave 3 do introduce the possibility of a differential loss to follow-up bias.18 Analyses of the baseline differences between youth respondents to either wave 2 or wave 3 and those who failed to respond did indicate that responders were significantly more likely to report having a home smoking ban. To help correct for biased attrition, we used variables that were significantly related to having a smoking ban (including parental education and youth smoking status) in an iterative raking procedure to create adjustments to the baseline weights.
A second limitation of this research is that it relied on youth report of home smoking policies. Although youth reports may be less accurate than parental reports, they measure youth perception, which may be more important than actual household restrictions.12
The evidence presented in this article supports the conclusion that the presence of complete household smoking bans significantly increases the likelihood that youths will develop antismoking attitudes and decreases the likelihood of youth smoking initiation by impeding the progression from nonsmoking to early cigarette experimentation among youths living with nonsmokers. This study supports the notion that home smoking bans have the potential to promote antismoking norms and to prevent adolescent smoking.
Acknowledgments
This work was supported by the Flight Attendant Medical Research Institute and the National Cancer Institute's State and Community Tobacco Control Interventions Research Grant Program (grant 2R01 CA86257).
Human Participant Protection
This study was approved by the institutional review boards of the University of Massachusetts Boston (survey administration and data collection site) and the Boston University Medical Center (data analysis site for the study described in this article).
