Frequency and risk factors related to smoking in cars with children present.
Montreuil, Annie ; Tremblay, Michele ; Cantinotti, Michael 等
Tobacco control legislation has been pivotal in reducing exposure
to second-hand smoke (SHS) as well as in changing the social norm that
smoking is an acceptable behaviour in public. (1) While legislation has
been effective in controlling SHS exposure in public places, adoption of
voluntary smoking restrictions in homes has lagged, (2) especially in
homes with smokers--87% of households of non-smokers in Quebec had a
complete smoking ban in 2013, compared to only 53% of households with at
least one smoker. (3) Voluntary smoking restrictions in privately owned
vehicles has also lagged. Seven percent of adults and 14% of adolescents
age 12-17 years in Quebec travel every day or almost every day in cars
in which someone is smoking. (4) SHS exposure is higher in disadvantaged
populations. In 2007-08, 27% of non-smoking adolescents (age 12-17
years) living in deprived neighbourhoods in Quebec reported frequent SHS
exposure in a car, compared to only 16% of those living in more
advantaged neighbourhoods. (5)
SHS exposure in cars can be particularly problematic among
children. (6) The concentration of fine particulate matter (i.e.,
<2.5 micrometres in diameter, referred to as [PM.sub.2.5]) in tobacco
smoke can quickly attain high levels in confined spaces. (7,8) WHO
guidelines state that to prevent illness, the average daily
concentration of [PM.sub.2.5] in the air should not exceed 25
[micro]g/[m.sup.3], and annual mean concentration should remain below 10
[micro]g/[m.sup.3]. (9) Yet Ott et al. (7) reported that smoke from only
two cigarettes smoked inside a car with the air conditioning on and the
windows closed would generate [PM.sub.2.5] concentrations of 42
[micro]g/[m.sup.3] in a 24-hour period, and others have reported similar
findings. (6,10,11) Even with the windows open and the ventilation
turned on, average [PM.sub.2.5] concentrations during a car ride in
which someone is smoking can exceed recommended levels of fine
particulate matter. (10) In Quebec, ambient temperatures during the fall
and winter months are not conducive to window-lowering.
On inhalation, [PM.sub.2.5] penetrates deep into the lungs. (12)
Even if the time spent in a vehicle is relatively short, [PM.sub.2.5]
increases the risk of asthma symptoms in children. (13) Among the 18% of
Quebec adolescents aged 12-17 years with asthma, 27% report that their
asthma attacks were caused by tobacco smoke. (14) However, parents often
underestimate the effects of SHS exposure in cars on their
children's health, even if their child suffers from asthma. (15)
To date, nine of ten provinces in Canada and one territory (Yukon)
have enacted legislation prohibiting smoking in privately-owned vehicles
transporting children. (16) Quebec is the only province in Canada with
no such legislation.
The objective of this study was to estimate the proportion of daily
smokers in Quebec who smoke while travelling in a car in which children
are present, and to compare the characteristics of smokers who do and do
not smoke in cars. Secondary objectives were to describe voluntary
restrictions on smoking in cars, and beliefs about the existence and
potential effectiveness of legislation prohibiting smoking in cars with
children present.
METHODS
In 2011-12, we conducted a cross-sectional survey among daily
smokers age >18 years in Quebec who travelled by car as a driver or
passenger in the presence of children age <16 years, at least once in
the previous month. The sample included smokers of low, moderate and
high socio-economic status (SES) in each of three geographic regions in
Quebec (Montreal metropolitan area, other metropolitan regions, rural
regions). Participant SES was proxied by the material deprivation level
(quintile 1 (least disadvantaged) to quintile 5 (most disadvantaged)) of
the neighbourhood in which the smokers surveyed lived (17) as indicated
by their home postal code. To ensure representation of all deprivation
quintiles across the three geographic regions, an equal number of
participants was targeted in each deprivation quintile in each
geographic region. The survey was conducted by an independent polling
firm. To increase the potential for an acceptable response proportion
and high-quality data, the research team consulted survey experts to
shorten the questionnaire and to improve the wording of the items; they
offered survey-specific training to the interviewers hired by the
polling firm; and they listened unobtrusively to interviews during data
collection to ensure that the survey protocol was respected. The project
received approval from the Comite d'ethique a la recherche du CHUM.
In a randomly selected sample of 37,489 valid telephone numbers,
34,042 households were considered eligible to participate in the study.
Of these, 23,296 households were successfully contacted and a member of
the household accepted to respond to three screening questions to
determine if there was an eligible participant in the household (i.e.,
age [greater than or equal to] 18 years, daily smoker, had travelled in
a vehicle with a person <16 years in the past 30 days), for a
household response proportion of 68%.
If more than one person in a household was eligible, the individual
with the next birthday was selected. (18) Eligible participants were
identified in 1,229 of the 23,296 households (5%). Two thirds (66%) of
persons eligible agreed to participate, but 56 were excluded because
after further verification of the inclusion criteria, they were in fact
ineligible. The final sample size was 754 and the response proportion
was 45%. Public Works and Government Services Canada have issued
guidelines for response targets in telephone surveys
(http://www.tpsgc-pwgsc.
gc.ca/rop-por/rapports-reports/comitephone-panelphone/page06-eng.html).
For surveys of high importance in terms of key policy decisions,
response proportion targets range between 40% and 60%.
One third (31%) of participants lived in metropolitan Montreal, 29%
lived in other metropolitan regions and 30% lived in rural regions
(region of residence was missing for 9% of the sample). Ten percent of
participants were in the first quintile of the material deprivation
indicator; 19%, 18%, 20% and 24% respectively were in the second, third,
fourth and fifth quintiles. Quintile could not be determined for 10% of
the sample due to missing or erroneous postal code data.
Study variables
Number of cigarettes smoked per day was assessed by:
"Currently, how many cigarettes do you smoke each day?"
Smoking in cars was measured by: i) "When you are in a
privately owned vehicle, how often do you smoke?"; ii) "When
you are in a privately owned vehicle in the presence of a person <16
years, how often do you smoke?"; iii) "In general, when you
are in a privately owned vehicle in the presence of a non-smoker age
[greater than or equal to] 16 years, how often do you smoke?"
(Response choices for items i), ii) and iii) were: always; more than
half the time; half the time; less than half the time; never; don't
know (DK)). Participants who answered "always", "more
than half the time", "half the time" or "less than
half the time" were coded 'smoking in cars', while
participants who answered "never" were coded 'not smoking
in cars'. Participants who smoked in cars were asked: "Think
about the last time you smoked in a privately owned vehicle in the
presence of a person <16 years. How long was the ride? (<15
minutes; 15-30 minutes; 30-60 minutes; >1 hour; DK)."
Data on smoking rules inside the car used most often were collected
by: "The next question concerns your own vehicle. If you do not own
a vehicle, think about the one in which you travel most often. Do you or
the owner of the vehicle allow smoking in the vehicle? (yes; no; DK). Do
you or the owner of the vehicle have any rules about smoking inside the
vehicle?" Response choices included yes, no, and DK. Participants
who responded "yes" were asked if any of the following rules
applied (response choices for each item were yes, no, or DK):
"Smoking is not allowed: i) when children <16 years are in the
vehicle; ii) when non-smokers 16 years or older are in the vehicle; iii)
unless the driver is alone; iv) unless the fan, air conditioning or
heating is on; v) unless the windows are open; vi) unless nonsmokers
agree; vii) are there other rules on the use of tobacco inside the car
than those just mentioned?" If the participant answered
"yes" to vii), he/she was asked to specify the rule.
Participants were asked if smoking is allowed in their home and if
there are specific rules about smoking in the home. Response choices for
both items were: yes, no, DK.
Knowledge about legislation prohibiting smoking in cars with
children present was measured by: "To the best of your knowledge,
in the province of Quebec, is smoking allowed in a privately owned
vehicle transporting a person <16 years? (yes; yes, but only with the
windows open; no; I don't know)." Participants who responded
"yes" were coded as 'knowledgeable about the (absence of)
legislation'.
Perception of the effectiveness of legislation prohibiting smoking
in privately owned vehicles transporting children <16 years was
measured by: "Do you think that legislation prohibiting smoking in
privately owned vehicles in the presence of people <16 years would
be: very effective, quite effective, moderately effective, not very or
not at all effective in preventing young people from being exposed to
tobacco smoke?"
Socio-demographic data included age, sex, highest level of
education completed (elementary; high school; CEGEP; university), annual
household income (ten categories from CAD <$10,000 to [greater than
or equal to] $200,000;DK), employment status (coded 'currently
employed' if self-employed or employed; 'not currently
employed' if student, on parental leave, sick or on strike,
unemployed, retired, homemaker, other, DK), number of persons age <18
years living in the household, and any adult non-smokers living in
household (yes, no).
Data analysis
The data were analyzed in simple frequency distributions and
cross-tabulations. We used multivariable logistic regression to identify
independent socio-demographic correlates of: i) whether participants
smoke in cars; ii) whether they smoke in cars when children age <16
years are present; and iii) knowledgeable about legislation prohibiting
smoking in cars when children are present. All data analysis was
conducted using SPSS 19.
RESULTS
Over half of participants were female, most were between age 18 and
44 years, 19% had a university degree, and 74% were currently employed
(Table 1). Compared to a representative sample of adults who smoked
daily in the province of Quebec, our sample of daily smokers who
recently travelled in a car with a child <16 years had higher
proportions of females, participants age 35-44 years, participants whose
highest level of education was high school and participants currently
employed (Table 1). Proportionately fewer were age [greater than or
equal to] 55 years, reported that their highest level of education was
elementary school and had an annual household income <$60,000. Three
quarters (75%) lived with one or more persons <18 years; 54% lived
alone or with other smokers; and 46% lived with at least one non-smoker.
Participants smoked 14-15 cigarettes per day on average. Half (48%)
indicated that smoking was completely prohibited at home, 28% indicated
that smoking was permitted at home but only under certain conditions,
and 24% indicated that there were no smoking restrictions at home.
One third of participants (36%) never smoked when travelling by car
and 64% smoked at least occasionally (Table 2). However, 76% reported
that they never smoked when travelling in a car in the presence of
children age <16 years, while 23% did smoke on occasion. Sixty-six
percent reported that they never smoked in a car in the presence of
non-smokers [greater than or equal to] 16 years.
Among those who smoked at least occasionally in the presence of
children, 40% indicated that the last time this happened, the trip was
<15 minutes;23% reported that the trip was 15-30 minutes, 21%
reported that it was 30-60 minutes and 16% reported that the trip was
more than one hour.
One third of participants (34%) reported that smoking was
prohibited in their car or in the car in which they travelled most
frequently; 30% reported that smoking was always permitted, and 36%
reported that smoking was permitted but only in certain circumstances
(Table 3). The most frequently reported restrictions were: in the
presence of children, only if a window was open, only if non-smokers
agreed and only with nonsmokers [greater than or equal to] 16 years.
Half of participants thought that it was illegal to smoke in cars
in the presence of children, even though there is currently no such
legislation in Quebec. Thirty-seven percent knew that it was not
illegal; 8% thought that smoking was permitted, but only with the
windows open; and 5% did not know or did not respond to the question.
Knowledge about legislation prohibiting smoking in cars with
children present was linked to smoking behaviour in cars. Twelve percent
of smokers who thought there was such legislation in effect reported
smoking in a car with children present, compared to 32% of smokers who
knew that there was no such legislation.
Among participants who travelled in cars with children, 42% thought
that legislation prohibiting smoking in cars would be very effective in
protecting children from SHS;19% thought it would be quite effective;
14%, somewhat effective; 11%, not very effective and 12% thought it
would be not at all effective.
Multivariable logistic regression analyses suggested that females
were less likely than males to smoke in cars (OR 0.57, 95% CI
0.41-0.80), but there was no difference by sex in the likelihood of
smoking in cars when travelling with children (Table 4). Smokers aged
[greater than or equal to] 55 years were less likely than younger
participants to smoke in cars (OR 0.23, CI 0.13-0.39) and to smoke in
cars when children were present (OR 0.26, CI 0.12-0.54). Participants
who reported that smoking was prohibited at home were less likely than
those who permitted smoking at home, to smoke in cars (OR 0.24, CI
0.17-0.35) and in the presence of children (OR 0.16, CI 0.10-0.25).
Education was not related to smoking in cars in general, but university
graduates were less likely than less educated smokers to expose children
to smoke in cars (OR 0.31, CI 0.16-0.57). Annual household income and
living with a nonsmoker were not related to smoking in cars or to
smoking in cars in the presence of children.
Older participants age [greater than or equal to] 55 years were
less likely than younger participants to know that there was no
legislation prohibiting smoking in cars in Quebec (OR 0.58, CI
0.34-0.98), whereas participants whose annual household income was
[greater than or equal to] $80,000 were more likely to know that such
legislation is not in effect in Quebec (OR 1.98, CI 1.05-3.74). Sex,
education and living with a non-smoker at home were not related to
knowledge about legislation prohibiting smoking in cars with children
present.
DISCUSSION
Quebec is the only province in Canada where legislation prohibiting
smoking in cars in the presence of children has not been enacted. In
2012-13, 34% of students in grade 6 to 12 in Quebec were exposed to
tobacco smoke in a car in the previous week compared to 17% of students
in the other provinces. (19) To date, there are no publications
describing barriers and facilitators to the implementation and
enforcement of this kind of legislation in other provinces. In Ontario,
300 notifications of violation were issued during the first nine months
after implementation in 2009 (personal communication, Ontario Campaign
for Action on Tobacco). Media coverage of these first notifications did
not report any problematic incidents or negative reactions among
smokers. In Ontario, Newfoundland and Prince Edward Island, police
officers are responsible for enforcing this law, which specifies that
the officer's estimate of the age of a child is sufficient proof of
his/her age. (20-22) Police officers are more likely to issue a
notification if they are permitted to stop a vehicle to verify
compliance with the law, compared to when they stop a car for another
reason (i.e., driving above the speed limit). Police being allowed to
stop a car to verify compliance apparently increases respect for the
law. (23)
In Quebec, population support for legislation prohibiting smoking
in cars with children present is high, even among smokers--84% of
smokers and recent former smokers agree that smoking should be
prohibited in cars when children are present. (24) Although the reasons
for the lack of legislation in Quebec are not clear, it may be that
decision makers perceive that targeting privately owned vehicles is an
intrusion on individual rights and/or they may anticipate difficulties
with enforcement of the legislation. (25-27)
The proportion of smokers who smoke in cars is similar to the
proportion reported in 2007 shortly after introduction of legislation in
Quebec that prohibited smoking in public places. (24) While it is
possible that participants in this current study did not report
accurately, these data would suggest many smokers are aware of the
impact of smoking in cars on the health of children and choose to reduce
this risk by not smoking in these circumstances. On the other hand,
fully 32% of smokers who knew that it was not illegal, did smoke in cars
when children were present, and our data on time in cars with smoking
suggest that many children may have had a biologically important dose of
exposure. That any smoker continues to smoke in cars when children are
present suggests that preventive intervention including legislation is
warranted.
Legislation that obliges people to behave in a certain way may seem
coercive or draconian (at least when first implemented) to persons who
are not aware of, or who minimize the dangers of their own behaviour. If
such legislation is implemented in Quebec, it will be important to
accompany it with education about the dangers of SHS in cars.
Half of smokers thought that legislation to prohibit smoking in
cars with children present was already enacted, perhaps because of
confusion with adoption of similar legislation in other provinces. This
suggests that such legislation may be relatively easy to implement in
Quebec, as well as effective. Indeed, Nguyen (28) reported that
legislation in Canada reduced exposure to SHS among children travelling
in cars, with no notable increase in smoking at home.
Limitations
Limitations of this study include that the data were based on
self-report, which could have resulted in misclassification. In
particular, the proportion of smokers who reported smoking in cars when
children were present may be underestimated because of social
desirability bias. The sampling frame required an equal number of
participants who smoked daily in each deprivation quintile. Therefore,
the prevalence of smoking in cars with children present is likely
underestimated since smokers in advantaged quintiles (more of whom are
university-educated and less likely to smoke) are over-represented.
Non-response among persons eligible to participate may also have
affected prevalence estimates.
CONCLUSION
The current study, carried out in 2011-12 in the province of
Quebec, provides evidence that approximately 23% of smokers smoke in
cars when children are present. Many smokers thought that legislation
prohibiting smoking in cars with children present was already in effect,
and most thought that such legislation would be effective. Overall these
data provide evidence that legislation prohibiting smoking in cars with
children present is needed in Quebec and that it would be effective. In
particular, if smokers are unable or unwilling to provide a smoke-free
environment in cars for children, it may be that this kind of
legislation is essential to assure that Quebec children are protected
from the health effects of exposure to SHS.
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Received: March 23, 2015
Accepted: June 12, 2015
Annie Montreuil, PhD, [1,2], Michele Tremblay, MD, [1,3] Michael
Cantinotti, PhD, [4] Bernard-Simon Leclerc, PhD, [3,5] Benoit Lasnier,
MSc, [1] Joanna Cohen, PhD, [6,7] Jennifer McGrath, PhD, [8] Jennifer
O'Loughlin, PhD [3,9]
[1.] Institut national de sante publique du Quebec, Montreal, QC
[2.] Departement de psychologie, Universite du Quebec a Montreal,
Montreal, QC
[3.] Departement de medecine sociale et preventive, Universite de
Montreal, Montreal, QC
[4.] Departement de psychologie, Universite du Quebec a
Trois-Rivieres, Trois-Rivieres, QC
[5.] CSSS de Bordeaux-Cartierville-St-Laurent, Montreal, QC
[6.] Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
[7.] Dalla Lana School of Public Health, University of Toronto,
Toronto, ON
[8.] Department of Psychology, Concordia University, Montreal, QC
[9.] Centre de recherche du Centre Hospitalier de l'Universite
de Montreal, Montreal, QC
Correspondence: Annie Montreuil, PhD, Institut national de sante
publique du Quebec, 190 Cremazie Est, Montreal, QC H2P 1E2, Tel:
514-864-1600, ext. 3529, E-mail: annie.montreuil@inspq.qc.ca
Sources of support: This project was funded by the Canadian
Institutes of Health Research (CIHR) and the Institut national de sante
publique du Quebec through a financial contribution from the Quebec
Ministry of Health and Social Services. J. McGrath holds a CIHR New
Investigator Award and Operating Grant (MOP97879). J. O'Loughlin
holds a Canada Research Chair in the Early Determinants of Adult Chronic
Disease.
Acknowledgements: The authors thank Erika Dugas for assistance with
preparation of the manuscript and Yan Kestens for his contribution to
the research protocol submitted for funding.
Conflict of Interest: None to declare.
Table 1. Comparison of selected characteristics of the current
sample of smokers age [greater than or equal to] 18 years with
those of a same-aged provincially representative sample of
smokers. Quebec, 2011-12
Study sample Provincial sample of
(N = 754) % adult daily smokers
([dagger]) (CCHS 2011-12) %
Male 42 55 *
Age, years
[less than or equal to] 34 33 32
35-44 35 16 *
45-54 19 23 *
[greater than or equal to] 55 13 29 *
Highest level of education completed
Elementary 7 23 *
High school 47 26 *
CEGEP 27 47 ([double dagger])
University 19
Missing 1 4 *
Annual household income
<$20,000 11 16 *
$20-$39,999 18 23 *
$40-$59,999 19 23 *
$60-$79,999 14 16
[greater than or equal 20 22
to] $80,000
Missing 18 --
Currently employed 74 66 *
Notes: CEGEP (College d'enseignement general et
professionnel; General and vocational college): In
Quebec, students graduate from high school after
completing grade 11 and attend CEGEP for a 2-year
pre-university program or a 3-year technical
program. CEGEP is equivalent to grade 12 and the
first year of a university undergraduate program
in other Canadian provinces.
CCHS = Canadian Community Health Survey.
([dagger]) Totals may not add to 100% because of
rounding.
([double dagger]) Combines CEGEP and University.
* Significantly different from the study sample (p
< 0.05).
Table 2. Frequency of smoking in privately owned
vehicles in general, when children age <16 years
are present, and when non-smokers age 16 years or
older are present, among daily smokers who travel
regularly [at least once in past 30 days] by car
in the presence of children age <16 (N = 754),
Quebec, 2011-12
Smoke In general When children When non-smokers
(N = 754) % age <16 years age [greater than
are present or equal to] 16
(N = 754) % years are present
(N = 754) %
Never 36 76 66
Less than half 24 13 18
the time
Half the time 18 6 7
More than half 8 1 4
the time
Always 14 3 4
Missing 0.3 0.1 1.5
Table 3. Smoking restrictions inside car used most often
among daily smokers who travel regularly in cars with
children age <16 years (N = 754), Quebec, 2011-12
Smoking permitted %
Never 34
Always 30
Not permitted in certain circumstances * 36
When people age <16 years are in the vehicle 27
Unless the windows are open 23
Unless non-smokers agree 21
When non-smokers age [greater than or equal to]16 18
years are in the vehicle
Unless driver is alone 12
Unless the fan, air conditioning, or heating is 8
turned on
Other 7
* Participants could check all that apply.
Table 4. Odds ratios (OR) and 95% confidence intervals (CI)
for smoked in privately owned vehicles, smoked in privately
owned vehicles transporting children age <16 years, and
knowledge about legislation prohibiting smoking in cars with
children present according to potential socio-demographic
correlates (N = 754), Quebec, 2011-12
Smoked in privately
owned vehicle (n = 746)
% OR (95% CI)
Sex
Male 70.0 Ref.
Female 60.1 0.57 ** 0.41 -0.80
Age, years
[less than or 68.5 Ref.
equal to]34
35-44 66.8 0.69 0.46-1.03
45-54 64.1 0.52 ** 0.32-0.84
[greater than 47.4 0.23 *** 0.13-0.39
or equal
to]55
Highest completed level of education
Elementary or 65.7 Ref.
high school
CEGEP 66.5 1.04 0.71-1.54
University 57.6 0.83 0.53-1.29
Annual household income
<$20,000 66.3 Ref.
$20-$39,999 66.7 1.30 0.69-2.44
$40-$59,999 66.7 1.31 0.69-2.48
$60-$79,999 62.7 1.05 0.53-2.07
[greater than 63.4 1.38 0.71 -2.72
or equal
to]$80,000
Missing 60.7 1.04 0.55-1.96
Adult non-smoker lives in household
No 64.7 Ref.
Yes 63.9 1.10 0.78-1.55
Smoking prohibited at home
No 75.0 Ref.
Yes 52.8 0.24 *** 0.17-0.35
Nagelkerke's 0.153
Pseudo
[R.sup.2]
Smoked in privately owned
vehicle with children age <16
years (n = 747)
% OR (95% CI)
Sex
Male 20.5 Ref.
Female 25.6 1.32 0.89-1.96
Age, years
[less than or 19.8 Ref.
equal to]34
35-44 27.2 1.39 0.87-2.22
45-54 31.2 1.35 0.79-2.31
[greater than 11.3 0.26 *** 0.12-0.54
or equal
to]55
Highest completed level of education
Elementary or 28.5 Ref.
high school
CEGEP 22.2 0.64 0.41-1.00
University 11.1 0.31 *** 0.16-0.57
Annual household income
<$20,000 35.0 Ref.
$20-$39,999 28.6 0.93 0.49-1.79
$40-$59,999 23.1 0.81 0.41 -1.58
$60-$79,999 17.5 0.65 0.30-1.39
[greater than 17.0 0.99 0.47-2.09
or equal
to]$80,000
Missing 23.7 0.80 0.41 -1.58
Adult non-smoker lives in household
No 26.7 Ref.
Yes 19.6 0.89 0.59-1.33
Smoking prohibited at home
No 36.8 Ref.
Yes 8.9 0.16 *** 0.10-0.25
Nagelkerke's 0.245
Pseudo
[R.sup.2]
Knowledge about legislation
prohibiting smoking in cars
with children present (n =
748)
% OR (95% CI)
Sex
Male 41.6 Ref.
Female 33.6 0.74 0.54-1.02
Age, years
[less than or 37.9 Ref.
equal to]34
35-44 37.5 0.82 0.56-1.19
45-54 40.8 0.99 0.63-1.55
[greater than 27.8 0.58 * 0.34-0.98
or equal
to]55
Highest completed level of education
Elementary or 35.3 Ref.
high school
CEGEP 37.3 1.01 0.70-1.45
University 41.7 1.19 0.78-1.82
Annual household income
<$20,000 31.3 Ref.
$20-$39,999 37.6 1.41 0.77-2.58
$40-$59,999 35.4 1.25 0.68-2.28
$60-$79,999 42.7 1.62 0.85-3.08
[greater than 47.1 1.98 * 1.0-3.74
or equal
to]$80,000
Missing 25.9 0.78 0.41-1.46
Adult non-smoker lives in household
No 35.2 Ref.
Yes 39.2 1.10 0.80-1.53
Smoking prohibited at home
No 38.7 Ref.
Yes 35.2 0.68 * 0.48-0.94
Nagelkerke's 0.053
Pseudo
[R.sup.2]
Notes: Participants with missing data were not included in
the multivariable analysis. The model included all variables
in the table concurrently.
* p < 0.05; ** p <0.01; *** p <0.001.
