Customize your JAMA Network experience by selecting one or more topics from the list below.
Farkas AJ, Gilpin EA, White MM, Pierce JP. Association Between Household and Workplace Smoking Restrictions and Adolescent Smoking. JAMA. 2000;284(6):717–722. doi:10.1001/jama.284.6.717
Author Affiliations: Cancer Prevention and Control Program, Cancer Center, University of California, San Diego.
Context Recent marked increases in adolescent smoking indicate a need for new
prevention approaches. Whether workplace and home smoking restrictions play
a role in such prevention is unknown.
Objective To assess the association between workplace and home smoking restrictions
and adolescent smoking.
Design, Setting, and Subjects Data were analyzed from 2 large national population-based surveys, the
Current Population Surveys of 1992-1993 and 1995-1996, which included 17,185
adolescents aged 15 to 17 years.
Main Outcome Measures Smoking status of the adolescents surveyed, compared by presence of
home and workplace smoking restrictions.
Results After adjusting for demographics and other smokers in the household,
adolescents who lived in smoke-free households were 74% (95% confidence interval
[CI], 62%-88%) as likely to be smokers as adolescents who lived in households
with no smoking restrictions. Similarly, adolescents who worked in smoke-free
workplaces were 68% (95% CI, 51%-90%) as likely to be smokers as adolescents
who worked in a workplace with no smoking restrictions. Adolescent smokers
were 1.80 (95% CI, 1.23-2.65) times more likely to be former smokers if they
lived in smoke-free homes. The most marked relationship of home smoking restrictions
to current adolescent smoking occurred in households where all other members
were never-smokers. Current smoking prevalence among adolescents in homes
without smoking restrictions approached that among adolescents in homes with
a current smoker but with smoking restrictions.
Conclusions Parents with minor children should be encouraged to adopt smoke-free
homes. Smoke-free workplaces can also augment smoking prevention. These findings
emphasize the importance of tobacco control strategies aimed at the entire
population rather than at youth alone.
Since the health risks of smoking became generally known following the
release of the 1964 surgeon general's report,1
adult smoking prevalence in the United States has declined steadily.2,3 Not only has adult cessation increased,2-4 but initiation of smoking
by adults became rare by 1980,5 when the age
of initiation of regular smoking had shifted from early adulthood to the midteenage
years or younger.6,7 Beginning
in the early 1970s, youth smoking also began to decline. However, in the mid-1980s,
the decline was arrested, and during the early 1990s, adolescent smoking increased
Although there is some indication that adolescent smoking declined slightly
from 1996 to 1998,11 the magnitude of the increase
in the 1990s alarmed many public health professionals and focused attention
on public policy to reduce adolescent smoking. Recent prevention efforts during
the 1990s have emphasized school programs, media campaigns, and enforcement
of laws restricting the sale of cigarettes to youth.
In 1991, we suggested that smoking restrictions in the workplace might
be an important public health strategy for reducing smoking in young adults.12 Hill and Borland13
reported that about a third of adult Australian smokers stated that they first
started smoking regularly at work. Workplace smoking restrictions can reduce
the opportunity to smoke, and thereby interrupt establishment of nicotine
addiction. A number of studies have shown that workplace smoking restrictions
are associated with increased cessation14-18
and reduced cigarette consumption.14,16-26
It is important to determine whether policies restricting smoking in
the workplace might be effective in reducing smoking among adolescents who
work. Although few young adolescents are employed, by midadolescence many
have part-time jobs. While there is evidence of an association between home
smoking restrictions and adult smoking behavior,27-29
there is little information about their potential impact on adolescents. Assuming
such an association, public policy that encourages parents to voluntarily
adopt home smoking restrictions might prove useful for prevention of adolescent
smoking. Two studies showed less smoking experimentation among elementary
school students living in households that restricted smoking30,31;
1 of these studies31 also examined middle school
students and found a similar effect. Only 1 study has examined home smoking
restrictions in relationship to smoking among high school students; it also
included middle school students and analyzed current regular smoking instead
of experimentation, but no significant relationship was demonstrated.32
The objective of this study was to examine whether household and workplace
smoking restrictions are associated with lower rates of adolescent smoking.
We used data from population-based surveys conducted in the 1990s that asked
questions about smoking and included adolescents 15 to 17 years of age. Thus,
we explore the relationship of smoking restrictions to current or former smoking
at the time of the interview.
We combined data from 6 monthly Current Population Surveys (CPSs) conducted
in 1992-1993 and 1995-1996 that contained a special Tobacco Use Supplement.33 The CPSs are conducted continuously by the US Census
Bureau for labor force monitoring; they cover the civilian, noninstitutionalized
population aged 15 years or older.34 The CPS
is a probability sample based on a stratified sampling scheme of clusters
of households, and typically surveys about 56,000 households containing approximately
110,000 persons each month. The labor force interviews are conducted with
an adult household member who responds for all eligible household members.
In contrast, the special Tobacco Use Supplement was individually administered
to each household member aged 15 years or older. Response rates for the CPS
Labor Force Core Questionnaire were over 93% for the 6 monthly surveys, while
the self-response rates for the Tobacco Use Supplement were over 84%. About
a quarter of the interviews were conducted in person with the remainder conducted
by telephone. We restricted the main analyses to the 17,185 teenaged self-respondents
who were 15 to 17 years of age when surveyed.
Smoking Status. Tobacco Use Supplement respondents were asked, "Have you smoked at least
100 cigarettes in your entire life?" Those responding "no" were classified
as never-smokers, while those responding "yes" were classified as smokers.
Smokers were asked, "Do you now smoke cigarettes every day, some days, or
not at all?" Respondents who answered "every day" or "some days" were classified
as current smokers while those who answered "not at all" were considered former
Household Smokers. Adolescent respondents were divided into 3 groups, depending on the
presence of current, former, and never-smokers aged 15 years or older in the
household. For this purpose, the smoking status of the other household members
was used even if obtained by proxy report. Adolescents in the first group
lived with never-smokers only; adolescents in the second group lived with
at least 1 former smoker but no current smokers; and adolescents in the third
group lived with at least 1 current smoker.
Home Smoking Restrictions. To determine the level of household smoking restrictions, respondents
were asked, "Which statement best describes the rules about smoking in your
home?" Response choices were: (1) no one is allowed to smoke anywhere, (2)
smoking is allowed in some places or at some times, or (3) smoking is permitted
anywhere. These responses were designated as smoke-free, partial ban, and
no smoking restrictions, respectively.
Workplace Smoking Restrictions. Employment status and workplace smoking restrictions were used to assign
each adolescent respondent to one of 5 categories. The workplace policy questions
were asked only of adolescents who worked in either the public or private
sectors and worked indoors but not in someone's home. Indoor workers were
asked, "Which of these best describes your place of work's smoking policy
for indoor public or common areas such as lobbies, rest rooms, and lunch rooms?"
and "Which of these best describes your place of work's smoking policy for
work areas?" Response choices for both questions were: (1) not allowed in
any (public/work) areas, (2) allowed in some (public/work) areas, and (3)
allowed in all (public/work) areas. Those who answered that smoking was "not
allowed in any public areas" and "not allowed in any work areas" were classified
as working in smoke-free workplaces. Those who only answered that smoking
was "not allowed in any work areas" were classified as working under a work-area
ban. The remaining indoor workers were classified as working under a partial
work-area ban. Depending on employment status, the remaining adolescents were
classified as either other workers (mostly outdoor workers or workers in someone's
home) or nonworkers.
School Enrollment and Hours Worked. School enrollment was ascertained by proxy or self-response for persons
16 to 24 years of age. In 1992-1993 the survey asked, "Last week was ( . .
. ) attending or enrolled in a high school, college or university?" and for
those 15 years or older employed in the previous week, "How many hours did
( . . . ) work last week at all jobs?" In 1995-1996, the questions changed
slightly: "Last week, was ( . . . ) enrolled in a high school, college or
university?" and "How many hours per week did ( . . . ) usually work at the
main job?" and "How many hours per week did ( . . . ) usually work at other
The public-use data files for the 6 surveys included a weighting variable
for self-respondents that ensures estimates from the combined sample for each
year (ie, 1992-1993, 1995-1996) are representative of the 1990 US population
by sex, age, race/ethnicity, and region. Besides adjusting for demographic
differences in nonresponse, the weights also take into account the sampling
χ2 Procedures were used to assess differences among percentages
(Yates-adjusted for 2 × 2 tables, and Mantel-Haenszel when a graded
response was expected). A result was considered significant for these tests
Logistic regression analyses included variables for age and school enrollment,
sex, ethnicity, survey year, the smoking status of other household members,
household smoking restrictions, and workplace smoking restrictions as independent
variables in 2 analyses with different dependent variables: (1) ever-smoking
and (2) in a nested analysis, cessation. For all percentages and odds ratios,
95% confidence intervals (CIs) were computed. Variance estimates were inflated
by a factor of 1.29 (design effect) to account for the deviation of the sample
design from a simple random sample of the US population.34
There were 1813 current and 386 former smokers, which we grouped as
ever-smokers. The total number of never-smokers was 14,986. Table 1 shows that the percentage (95% CI) of adolescents (15-17
years old), who lived in smoke-free households increased significantly from
47.8% (±1.1%) in 1992-1993 to 55.0% (±1.3%) in 1995-1996. This
was true regardless of the smoking status of other household members, but
adolescents living with current smokers were less likely to live in smoke-free
homes at either time. While the percentage of adolescents who worked outside
the home increased from 22.8% (±0.9%) to 27.2% (±1.2%) from
1992-1993 to 1995-1996, the percentage of adolescent in-door workers in smoke-free
workplaces increased from 22.7% (±1.9%) to 40.0% (±2.4%). The
mean (SD) for hours worked during the previous week by employed adolescents
was 16.0 (9.6), which indicates that most adolescents were part-time workers.
Table 2 shows the likelihood
that an adolescent was a smoker according to age and school enrollment, household
composition, and level of smoking restrictions. While most of the 16- and
17-year-olds were enrolled in school, 4.2% (95% CI, ± 0.7%) of the
16-year-olds and 9.4% (95% CI, ± 1.0%) of the 17-year-olds had dropped
out. The odds ratios were adjusted for demographics (sex, race/ethnicity,
survey year) not shown and the remaining variables in the analysis. Older
adolescents were more likely to be smokers than younger adolescents and drop
outs were particularly likely to be smokers. Adolescents living with current
smokers were 3 times as likely to be smokers than those living with never-smokers,
but those living with at least 1 former smoker (and no current smokers) were
only about 1.66 (95% CI, 1.37-2.01) times more likely to be smokers. Adolescents
living in smoke-free homes were 0.74 (95% CI, 0.62-0.88) times as likely to
be smokers as those living in homes with no smoking restrictions; partial
bans had no significant effects on adolescents not smoking. In addition, adolescents
who worked indoors in a smoke-free workplace were 0.68 (95% CI, 0.51-0.90)
times as likely to be smokers than those who worked indoors with a partial
work-area ban. Nonworking adolescents were 0.77 (95% CI, 0.63-0.95) times
as likely to be smokers as indoor workers with a partial work-area ban.
Adolescents who live in smoke-free homes are half as likely to be smokers
as those living in homes with no restrictions, regardless of their school
enrollment status (Figure 1). Further,
adolescents enrolled in school who work in smoke-free workplaces are significantly
less likely to be smokers than other workers and those working under a partial
indoor ban (Figure 2), but workplace
restrictions appear to have little effect on dropouts.
Table 3 shows the likelihood
that an adolescent smoker was in cessation when interviewed according to age
and school enrollment, household composition, and levels of smoking restrictions.
Again, the odds ratios are adjusted for other demographics and the remaining
variables in the analysis. The likelihood of cessation was 1.60 (95% CI, 1.09-2.33)
times higher for adolescents living with a former smoker (but no current smokers)
compared with those living with a current smoker, but adolescents living with
only never-smokers did not show significantly increased cessation.
Adolescents living in smoke-free households were 1.80 (95% CI, 1.23-2.65)
times more likely to be in cessation than those living in households with
no restrictions on smoking. Partial smoking restrictions were not significantly
associated with cessation. Unlike ever-smoking, cessation was not significantly
related to workplace smoking restrictions.
Adolescents living with a current smoker had the highest smoking prevalence
(Figure 3). Prevalence was about
the same for adolescents living with a current smoker under either a partial
smoking ban or in a smoke-free home, but was lower compared with those with
no household smoking restrictions (P = .02). In households
with a former smoker (but no current smokers), there was no significant relationship
between smoking restrictions and prevalence (P =
.09). When adolescents lived only with never-smokers, however, the level of
home smoking restriction was highly associated with prevalence (P<.001). Note that prevalence for the group with no home smoking
restrictions was only slightly higher than prevalence in households with at
least 1 former smoker, and it approached the level for adolescents living
with a current smoker in households with only a partial restriction.
The results from these national surveys strongly suggest that smoke-free
workplaces and homes are associated with significantly lower rates of adolescent
smoking. Further, even after adjustment for the presence of smokers in the
household and school enrollment, smoke-free homes have a greater association
with lower rates of smoking prevalence than smoke-free workplaces. In addition,
smoke-free homes were associated with an increased likelihood of smoking cessation
in adolescent smokers. Complete rather than partial bans on smoking in the
home and in the workplace produced the most significant associations.
Because only about 25% of adolescents are employed, smoke-free homes
should affect adolescent smoking more than smoke-free workplaces. Although
a smoke-free workplace was associated with a significantly reduced likelihood
of an adolescent becoming a smoker, it may not completely counter the influence
of the increased income a job provides. Adolescents with more spending money,
either from employment or other sources, are more likely to smoke, and smoke
more on average than adolescents with less discretionary spending money.35
It is well-known that adolescents of parents who smoke are more likely
to become smokers.36-39
Our results were adjusted for the smoking status of other household members,
generally the parents. We previously showed that adolescents whose parents
had quit smoking were only about two thirds as likely to be smokers as those
with a parent who still smoked.40 Further,
adolescent smokers whose parents had quit were twice as likely to be former
smokers when surveyed than those with a parent who still smoked. Finally,
the earlier in the adolescent's life that parents quit, the lower the risk
of their adolescent smoking. Adult smokers (18 years or older) who lived or
worked under smoke-free conditions were more likely to be actively trying
to quit and were more likely to be in cessation for at least 6 months when
surveyed than were those reporting no home or workplace smoking restrictions.28 Thus, smoke-free homes and workplaces may also have
an indirect effect on adolescent smoking by encouraging parental cessation.
Adoption of a smoke-free home policy sends a message to family members
that smoking is not condoned, while the lack of such a policy may send the
opposite message. Adolescents who lived in households without a complete ban
where all of the other members were never-smokers were nearly as likely to
be current smokers as adolescents who lived in households with a current smoker
and at least partial household smoking restrictions. Public health policy
should continue to educate the population concerning the dangers of secondhand
smoke and stress that adopting smoke-free homes is something concrete that
parents can do to influence their children not to smoke.
Tobacco control efforts should also continue to encourage smoke-free
workplace ordinances throughout the United States. Besides protecting nonsmokers
from secondhand smoke and encouraging smoking cessation among adults, smoke-free
workplaces may be an important strategy for reducing the percentage of adolescents
who become smokers. Adolescents who experiment with smoking and spend a significant
amount of their time at work where smoking is prohibited may not be as likely
to progress to established smoking. However, longitudinal studies are needed
to establish this link.
There are some limitations to the present study. It is not longitudinal.
Thus, the results, while suggestive of important associations, are not definitive.
Smoking status is by self-report, and it is not validated by biochemical assay;
however, studies of adolescents have shown that there is stability of self-reported
substance use and that questionnaires provide reliable data.41
Second, telephone surveys of adolescents often produce lower smoking prevalence
estimates than school surveys.7 The CPS measure
of smoking (at least 100 cigarettes in one's lifetime) may be less sensitive
to underreporting. Adolescents who have smoked a fair amount are probably
less inclined to try to hide it from parents (they likely already know) or
to be embarrassed about it with the interviewer. Finally, there is the issue
of reporting discrepancy regarding home smoking restrictions by adolescents
compared with household adults. Household adults also were asked about household
smoking restrictions, and the agreement among parents and adolescents was
high (81%). When there was a household consensus, about the same percentage
of adults reported more restrictive smoking policies (9%) as less restrictive
policies (10%) when compared with the adolescent. Perceived policy is probably
more important than actual policy set by household adults; if adolescents
think there are smoking restrictions, it is likely that they will act accordingly.
In summary, our findings suggest an important role for smoke-free homes
and workplaces in reducing adolescent smoking. More importantly, they stress
the importance of targeting tobacco control interventions to the entire population
for primary prevention rather than emphasizing special programs aimed only
at adolescents. As the prevalence trends in the mid-1960s and early 1970s
for adults and adolescents indicate, it is likely that another downturn in
adolescent smoking would follow a significant further decline in adult smoking.