Legislative smoking bans for reducing secondhand smoke exposure ...

Northern Ireland. Similar legislation restricting smoking further in
the hospitality sector has been implemented in Italy, Spain, Malta
and France. Smoking ban legislation is usually preceded and often
followed by public awareness activities, as well as interventions to
promote smoking cessation such as those outlined in NICE 2007.
Smoking bans and restrictions may have the potential to affect
a large number of individuals in a population at minimal cost
and to create a supportive environment for those who want to
quit, thereby helping people who continue smoking to reduce
their tobacco consumption. Fichtenberg 2002, in a review of the
effects of totally smoke-free workplaces on daily consumption and
smoking prevalence, estimated that such policies reduced smoking
prevalence by 3.8%. An earlier review, however, although detecting
reduced daily consumption in totally smoke-free work sites, was
not able definitively to separate this effect from possible secular
trends (Chapman 1999). The stable long-term effect of bans and
restrictions remains an open question.
O B J E C T I V E S
The overall objective is to assess the extent to which smoking bans
or restrictions reduce tobacco consumption, smoking prevalence,
and exposure to secondhand smoke.
Primary objectives:
Does the imposition of bans or restrictions have an effect on exposure
to secondhand smoke?
Does the imposition of bans or restrictions reduce tobacco consumption
and smoking prevalence in the area affected by the ban
or policy?
Secondary objective:
What effect does the imposition of bans or restrictions have on
the smoking-related morbidity and mortality of those affected by
the ban or restriction?
M E T H O D S
Criteria for considering studies for this review
Types of studies
We considered studies that report smoking bans which have been
implemented as a result of legislation. The smoking ban must
operate at national, state or community level. We do not include
in this review settings-based bans, such as in workplaces, where
smoking has been partially or comprehensively restricted, though
not necessarily as a result of national or state-level legislation.
The minimum standard was having a ban explicitly in the study
and a minimum of six months follow up for measures of smoking
behaviour. We searched for randomized controlled trials, quasi-experimental
studies (i.e. non-randomized controlled studies), controlled
before-and-after studies and interrupted-time series, as defined
by the Cochrane Effective Practice and Organization of Care
Group (EPOC 2009 ) and uncontrolled pre- and post-ban data.
Types of participants
Smokers and nonsmokers exposed to comprehensive or partial
smoking bans. The bans must be implemented by legislation or
policy-making, and may affect populations at a local, regional, or
national level.
Types of interventions
Legislative bans which either ban smoking completely (comprehensive)
or restrict it to designated areas (partial). For controlled
studies, the intervention setting may be compared to settings without
smoking bans or with less restrictive policies. The ban may be
implemented at national, regional or local level.
Types of outcome measures
The primary outcome measures are:
1. Measures of exposure to secondhand smoke among those affected
by the ban, including:
a) measurement of biological markers of exposure in physiological
fluids e.g. cotinine, or in expired air
b) self-reported exposure to SHS
2. Measures of smoking behaviour among those affected by the
ban, including:
a) prevalence of tobacco use
b) tobacco consumption
c) cessation rates
The secondary outcome measure is:
Measures of health outcomes relating to morbidity and mortality,
e.g. cardiac admissions, respiratory health, and pulmonary function.
In studies with longer follow up, measures of the incidence
of lung cancer and cardiovascular disease may also be available.
We preferred biochemically verified smoking cessation over self
report, and sustained or prolonged cessation over point prevalence
cessation. We preferred biochemical verification of exposure
to environmental tobacco smoke over self-reported perceptions.
However, we did not exclude studies which did not verify these
measures biochemically. In order to assess sustained impact, we
included studies which reported outcomes such as smoking behaviour
at least six months after the start of the smoking restriction
Legislative smoking bans for reducing secondhand smoke exposure, smoking prevalence and tobacco consumption (Review)
Copyright © 2010 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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