Volume 2: No.
4, October 2005
The Cost-Effectiveness of
1% Or Less Media Campaigns Promoting
Low-Fat Milk Consumption
Margo G. Wootan, DSc, Bill Reger-Nash, EdD, Steve Booth-Butterfield, EdD,
Linda Cooper, MSW, LCSW
Suggested citation for this article: Wootan MG, Reger-Nash B, Booth-Butterfield S,
Cooper L. The cost-effectiveness of 1% Or Less media campaigns
promoting low-fat milk consumption. Prev Chronic Dis [serial online] 2005 Oct [date cited].
Available from: URL: http://www.cdc.gov/pcd/issues/2005/
The purpose of our study was to compare the cost-effectiveness of four strategies
using components of 1% Or Less to promote population-based behavior change. 1% Or Less
mass-media campaign that encourages switching from high-fat (whole or 2%) to low-fat
(1% or skim) milk.
Using a quasi-experimental design, campaigns were previously conducted in four
West Virginia communities using different combinations of 1) paid advertising, 2) media
relations, and 3) community-based educational activities. Telephone surveys and supermarket milk sales data were used to measure the campaigns’
Using data from the previously completed studies,
we analyzed the cost of each campaign. We then calculated the cost per person
exposed to the campaign and cost per person who switched from high- to low-fat
The combination of paid advertising and media relations was the most
cost-effective campaign, with a cost of $0.57 per person to elicit a switch from high-
to low-fat milk, and the combination of media relations and community-based educational
was the least cost-effective campaign, with a cost of $11.85 per person to elicit
Population-based campaigns using a combination of paid advertising and media
relations strategies can be a cost-effective way to promote a behavior change in
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Milk and health
Numerous epidemiological studies indicate that diet plays a major role in
premature morbidity and mortality in the United States (1). Poor diet and a lack
of physical activity may eventually overtake smoking as the leading
preventable causes of death (2). Campaigns promoting positive changes in dietary
behavior have great potential for improving the public’s health.
Milk is a good choice for use in a community campaign to improve health
behaviors because it is consumed by so many people and plays an important role
in health and the diet. High-fat milk contributes significant amounts of excess
calories and saturated fat to the American diet, is the third-leading source of
saturated fat in the diet of American adults, and is the leading source of
saturated fat in the diets of children aged older than 2 years (3-6). Saturated
fats raise blood cholesterol levels and increase the risk of coronary heart
disease (1,7). In contrast, skim milk has 40% fewer calories and 5 fewer grams
of saturated fat per cup than whole milk. Only six types of food contribute
about half of the saturated fat consumed by American adults (4), so we chose one
of the items — milk — as the focus of our campaign. (A more recent study found
that seven types of food contribute half of the saturated fat consumed by the
average American .)
1% Or Less campaigns
Mass-media campaigns may be an effective way to address diet-related
population health behaviors, and paid mass-media campaigns have been shown to be a
useful way to deliver a public health message to numerous people (8).
Use of paid television, radio, and newspaper advertising combined with effective
media relations have been shown to significantly affect health behaviors when
a high level of market penetration is achieved (i.e., when the target audience
is repeatedly exposed to the campaign message) (9).
In 1995, The Center for Science in the Public Interest began developing a mass-media
community campaign — 1% Or Less — to encourage one important behavioral
change: switching from high-fat (whole or 2%) to low-fat (1% or skim) milk (10).
The campaign involved three basic components: 1) paid advertising, 2) media
relations, and 3) community-based educational programs. The campaign was
implemented in numerous communities nationwide, and the results of the pilot campaigns have
been published (11-13).
In this study, we assess the cost-effectiveness of various combinations of the
1% Or Less
campaign components in four individual West Virginia communities. We compare the
cost, exposure, and outcomes to the campaign message of the four different
types of campaign combinations: 1) paid advertising, media relations, and
community-based educational activities; 2) paid advertising and media relations;
3) media relations and community-based educational activities; and 4) paid
advertising alone. The paid advertising component consisted of professionally produced, strategically placed television, radio, and newspaper advertising.
Media relations comprised events
designed and implemented to generate coverage by the local news media. The
community-based educational activities included events such as blind milk taste tests in
grocery stores, point-of-purchase signs about the program, school activities
such as poster-design contests, and nutrition seminars conducted by trained
speakers at work sites and for various organizations.
Background of analyzed studies
The health goal of the campaigns was to encourage community members (older
than 2 years of age) to switch from high-fat to low-fat milk. The health communications research goal was to understand how the
various combinations of the three 1% Or Less components work in community-based
campaigns. The methodology was approved by the West Virginia University
Institutional Review Board.
A quasi-experimental design was used in communities with
populations ranging from 18,000 to 35,000. Each of the four communities received an intensive
6- to 8-week campaign, and each campaign involved a different combination of the
three 1% Or Less components (Table 1). The campaigns had a rolling field
experiment design. All campaigns were conducted during
February and March for 3 consecutive years beginning in 1996 (Table 1). A matched comparison community for
each campaign community was observed and received none of the campaign messages.
None of the communities had overlapping media markets and thus were not exposed
to the other communities’ 1% Or Less campaign messages. All four communities
had similar demographics, and their campaigns had similar budgets (11-13).
The Clarksburg, Beckley, and Wheeling campaigns all incorporated the paid
advertising component and delivered the 1% Or Less message to television
viewers (and therefore to significantly more people than those actually living in the
cities for which data were collected). The television message was delivered to approximately
278,000 (Clarksburg), 363,000 (Beckley), and 418,000 (Wheeling) viewers (11-13). The Parkersburg campaign, which did not incorporate the paid
advertising component but had extensive local newspaper coverage, delivered the
1% Or Less message to approximately 22,500 community members, which is the
number of people who subscribed to the local daily newspaper.
The first trial was conducted in Clarksburg and included all three 1% Or Less
components (paid advertising, media relations, and community-based educational
activities) (11). The campaign in Wheeling consisted of paid advertising and
media relations (12), and the Parkersburg trial involved a combination of media
relations and community-based educational activities (13). The community trial
in Beckley involved paid advertising only (13). The Parkersburg and Beckley
campaigns were conducted simultaneously and were compared with the same
In each campaign and comparison community, we conducted random-digit–dial
telephone surveys of milk purchasing and consumption habits for approximately
400 adults immediately before the beginning of the campaign (11-13). A panel
design was used. We called the baseline respondents again immediately after the
campaign and were able to reinterview 69% of the respondents in
Clarksburg, 73% in Wheeling, 67% in Parkersburg, and 67% in Beckley. We collected 1 month of fluid milk sales data from all supermarkets in
the campaign and comparison communities for the month immediately before and
the month immediately after (i.e., beginning the day after), 6 months after, and 12 months after the campaigns ended.
In addition, 2 years after the campaign ended in
Wheeling, we collected fluid milk sales data for 1 month. Communities were
not randomly assigned to campaign or control.
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Campaign costs (not including evaluation costs for telephone survey and milk sales data
collection) were determined by adding the
costs of the paid media advertising, personnel salaries, travel, communications,
incentives, and meetings. These data provided a total campaign cost per
community. The costs per person exposed to the campaign and per person who
switched from high- to low-fat milk were determined for each approach based on
the telephone survey responses received at the immediate end of the campaigns.
The primary outcome measures for the study were milk consumption survey
self-reports and supermarket milk sales from the campaign and comparison
communities. We compared precampaign and postcampaign (immediately after the
campaign) milk consumption and sales and compared precampaign and 6 months
postcampaign milk sales.
For self-reported consumption and milk sales, we computed effect sizes (r
and d), comparing changes in campaign communities with changes in
comparison communities (14). Using Cohen’s conventions for interpreting effect
size (14), we defined a small effect as an r from 0.1 to 0.2
or a d from 0.2 to 0.4; a medium effect as an r from
0.3 to 0.4 or a d from 0.5 to 0.7; and a large effect as
an r of 0.5 or greater or a d of 0.8 or greater. However, we did not
compute an effect size for the campaign community, compute an effect size for the
comparison community, and then perform the analysis. Although our computation is
conservative, it allows direct comparisons within each of our campaigns and does
not overly weigh extreme results.
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Changes in low-fat milk sales
The Clarksburg campaign included paid advertising, media relations, and
community-based educational activities, which increased low-fat milk sales from
18% to 41% (Table 2). The low-fat milk sales were still higher (33%) 1 year
after the campaign ended. Wheeling’s campaign involved paid advertising and
media relations and increased the low-fat milk sales from 29% to 46%, a change
that was sustained at 42% 2 years after the campaign ended. Analysis shows that
the increases in low-fat milk sales were statistically significant in the
Clarksburg and Wheeling campaigns (Table
3) (Table 4). Smaller increases in low-fat
milk sales were documented after the Parkersburg campaign, which used media
relations and community-based educational activities, and after the Beckley
campaign, which only used paid advertising. The increases were not significant.
Tables 3 and 4 provide the descriptive statistics for low-fat milk sales in
each of the four communities. The treatment effect for the precampaign to
postcampaign (the day after the campaign ended) increase in low-fat milk sales
(expressed as r) ranged from 0.01 (for the paid advertising campaign in
Beckley) to 0.64 (for the Clarksburg campaign, which used paid advertising, media
relations, and community-based educational activities) (Table 3), with a mean of 0.41. The average d effect size was 1.01 (z = 2.89,
P = .002), which is a large effect. Increases in sales of low-fat milk in
campaign communities were an average of 1 standard deviation larger than in
comparison communities. No statistically significant between-group heterogeneity
was found (χ2 <1.00); that is, no statistically significant
differences were found between campaigns, in spite of the large differences in
effect sizes. However, given the wide range of effect size results (0.02 in
Beckley to 1.67 in Clarksburg), the lack of statistically significant
heterogeneity may be a result of the small sample size.
The precampaign to 6-month postcampaign effect (r) for low-fat milk
sales ranged from 0.01 (Beckley) to 0.59 (Clarksburg) (Table 4). The average d
effect was 0.84 (z = 2.89, P = .002), which is also a large
effect. Increases in low-fat milk sales in campaign communities were an average
of 80% of a standard deviation larger than in comparison communities. Assessment of
between-group heterogeneity revealed no differences (χ2
Self-reported switching to low-fat milk
The treatment effect across the four 1% Or Less campaigns as measured by
survey respondents who reported switching from high- to low-fat milk ranged
from 13% (Beckley) to 38% (Clarksburg) (Table 5). In Clarksburg, 38% of respondents who reported
consuming whole or 2% milk before the campaign reporting drinking 1% or fat-free
milk immediately after the campaign (P <.001). In Wheeling, 34% switched from
high- to low-fat milk after the campaign (P <.001). In Parkersburg,
20% (P <.001) switched, and in Beckley, 13% (P
Expressed as an r effect, the switching rates range from 0.10
(Beckley) to 0.39 (Wheeling),
with a mean of 0.25. The average weighted d effect size was 0.53 (z
= 3.03, P <.001), a medium effect (Table 6). These results indicate that
self-reported switching in campaign communities was approximately half a
standard deviation greater than in the comparison communities. A test for
heterogeneity indicated significant heterogeneity between the different
campaigns (χ23 = 8.606;
= .02) measured at
the survey sample. Although the average effect was significant, results suggest
a discernable difference in the effectiveness of the various campaigns.
Campaign exposure was assessed by asking telephone survey respondents about
their awareness of the 1% Or Less message. The last column of Table 5 shows
percentages of self-reported exposure to the campaigns in the four campaigns. We
computed a linear contrast among the four effects (weights of 3, 1, −1,
and −3), producing a significant effect
(z = 3.161;
= .003). We also explored the possibility of nonlinear effects
(weights 1, −1, −1, 1) and found a smaller but still significant
effect (z = 2.12, P
We used several comparisons to explore patterns of nonlinearity. The
strongest pattern suggests that campaigns in Clarksburg and Wheeling resulted in
greater changes in low-fat milk consumption than in Parkersburg and Beckley (z =
2.72, P = .003) (Table 6). No
reliable difference between the effects of the
Clarksburg and Wheeling campaigns (z <1.00) was found, nor was a
reliable difference found between the Parkersburg and Beckley results.
The cost of each campaign is shown in
Table 7. Overall costs of each campaign
were similar, ranging from $43,000 (Wheeling) to $61,000 (Clarksburg). In
contrast, the number of people exposed to each campaign varied widely. As a
result, the approximate cost per person exposed to each campaign ranged from
$0.10 (Wheeling) to $2.27 (Parkersburg).
We estimated how much it cost in each campaign to cause one person to switch
from high- to low-fat milk. The wide variation in the number of people exposed
coupled with differences in switching rates among the campaigns contributed to a
wide range in cost. The cost to cause one person to switch from high- to low-fat
milk ranged from $0.57 (through the paid advertising and media relations
campaign in Wheeling) to $11.85 (through the community-based educational
activities and media relations campaign in Parkersburg). The combination of paid
advertising and media relations in Wheeling cost approximately $0.10 per person
exposed, whereas the Parkersburg campaign (which involved media
relations and community-based educational programs) cost $2.27 per person
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All campaigns effectively encouraged people to switch from high- to low-fat
milk, but the most cost-effective campaign was the Wheeling campaign combination of paid
advertising and media relations. In Wheeling, 34% of high-fat milk drinkers
switched to low-fat milk, with a cost of $0.57 per person (Table 7). In
addition, statistical analyses show that switching from high- to low-fat milk was not
significantly enhanced by the addition
of community-based educational programs, and the costs and complexity of the
campaigns were greatly reduced when they were not included.
Overall, the results of our analysis of the previous campaigns suggest that the combination of paid
advertising and media relations and the combination of paid advertising, media
relations, and community-based educational programs are more cost-effective than the
combination of media relations and community-based educational programs or paid
advertising only. The effect sizes were significantly larger in the two
communities that received a campaign combination of paid advertising and media relations. In addition, the two campaigns were more cost-effective,
with an estimated cost per person who switched of $0.57 (Wheeling) and $0.73
(Clarksburg), compared with $1.56 for the paid advertising only (Beckley) and $11.85 for the media relations and community-based educational activities
combination (Parkersburg) (Table 7). We designed the four campaigns so that they
would roughly cost the same amount because the communities were approximately
the same size (i.e., were all small, rural cities).
Media relations enhanced the impact of paid advertising. The campaign with paid
advertising only resulted in approximately 13% of high-fat milk drinkers
switching to low-fat milk, compared with 34% in the campaign in which paid
advertising was reinforced by media relations (Table 5).
The level at which community members were exposed to the campaign message is
a likely contributing factor in the varying effectiveness levels of the four 1%
Or Less campaigns. A linear relationship was found between campaign exposure and
the percentages of people switching from high- to low-fat milk. Survey data
suggest that some communities had high exposure rates, with 84% in Wheeling and
90% in Clarksburg (Table 5). In other studies, lower exposure campaigns also had
less impact (15).
We suggest that health educators change their approach. Although paid
media-based campaigns may seem expensive to traditional health educators, our
study suggests that paid media-based campaigns are more cost-effective than
traditional approaches because of lower personnel and material costs, broader
exposure, and greater message reinforcement. Public health organizations may
perceive community-based educational programs as more cost-effective because staff
costs are already incorporated into their budgets, whereas discretionary funding
for advertising is not. However, in the 1% Or Less campaigns, we found the
traditional community-based educational program approach to be the least
means of switching people to low-fat milk. Furthermore, it is inappropriate to
consider overall campaign costs only. The more relevant variable is cost per
person who switched.
Several public health publications state that mass media cannot effectively
cause population-based health behavior changes. For example, the National Cancer
Institute’s publication Making Health Communication Programs Work (15)
and the National Cholesterol Education Program’s Communications Strategy
for Public Education (16) argue that health communications alone cannot
produce behavior changes; however, the claims are not directly substantiated by any
or data. In sharp contrast, the food industry uses mass media as a
primary means of influencing food choices, spending about $26 billion per year
in advertising and promotions (17).
Evidence is mounting that properly designed mass-media campaigns can produce
significant and positive results (8,11-13,18). We subsequently used a media-based
approach to promote walking (18). The group exposed to an 8-week media campaign
on walking demonstrated a 14% net increase in 30 minutes of moderate-intensity
daily walking compared with a control community. The Centers for Disease Control
and Prevention’s (CDC’s) VERB campaign uses paid advertising, public relations
activities, and community events to encourage children aged 9 to 13 years to be
physically active (19). The results from the first year of this national media
campaign show measurable increases in activity levels in key segments of the target audience, including among girls and among
children from low-income families (20). Media-based tobacco campaigns have also
had positive results (21-23). Effective campaigns that reach broad audiences may
be even more cost-effective for promoting nutrition-related behavior change than
for decreasing tobacco use because everyone obviously needs to eat, whereas not
everyone uses tobacco. Furthermore, the overwhelming majority of Americans
(approximately 88%) do not follow federal dietary recommendations (24); perhaps
the enormous spending for advertising by the fast-food industry plays a role in
Health educators need to join forces with social marketing specialists and
sophisticated media production firms to produce high-quality, effective
materials. The original 1% Or Less message was designed by public health,
nutrition, marketing, and advertising specialists. In our study, we chose an
advertising firm (Zimmerman & Markman, Los Angeles, Calif) to design and
produce our television, radio, and print advertisements. After the materials
were produced, we worked with a professional media buyer to strategically place
the advertisements in a way that would best reach a target audience within the
Strategic placement of advertisements can result in delivery of a high-impact
message and reach the intended target audience. In contrast, health educators
using advertisements without professional assistance may spend their time and
resources producing public service announcements that result in little market
penetration (25). We know of no effective nutrition education campaigns that
effectively used public service announcements to produce a significant
communitywide behavior change.
Without market penetration (i.e., if campaigns do not reach their intended
target), campaigns have little possibility of success. The
costly and unsuccessful COMMIT trial failed to promote smoking cessation among
heavy smokers — the campaign target (26). Overall, telephone survey respondents
reported little knowledge of the COMMIT
campaign. (However, in certain communities with more market penetration,
the campaign impact was greater.) Although market penetration is a necessary
condition for behavioral change, market penetration alone will not result in
Our study has implications for primary prevention of heart disease and
obesity. Switching from whole to skim milk could result in 5 fewer pounds of fat
being consumed by a person in a year. (Because we had individual respondent data from precampaign and postcampaign
surveys that were only 3 months apart, we did not anticipate any measurable
changes in participants’ body weight.)
The generalizability of the 1% Or Less low-fat milk campaign results is
limited by the small number of communities and the lack of random assignment. In
addition, the campaigns were conducted at the community level, whereas the
telephone survey results were analyzed at the individual level. Our community
campaign had survey ecological and survey population measures. No indication
shows that a secular trend altered the communities in a way that might have
affected the outcomes. The four campaigns and outcome measures spanned
Finally, the campaigns were implemented in small-city markets. We are unsure how successful the
1% Or Less campaign would be in
large media markets. We successfully promoted our campaigns as newsworthy and
achieved coverage on television news programs and the front page of local
newspapers in media markets of 278,000 to 418,000 individuals. Although the
campaigns were prominent news items in small media markets, generating news
coverage in substantially larger media markets would be more difficult.
Additional 1% Or Less campaigns need to be tested in the media markets of larger
Despite these limitations, the data are compelling. The pretest-to-posttest
design and measurement of self-reported behavior and communitywide sales provide
consistent data with relatively good control (27). The results suggest that
dietitians and other health educators should consider the combination of paid
advertising and media relations as a central dietary change strategy. The
approach might be used as a cost-effective way to promote other dietary changes
such as eating more fruits and vegetables or whole grains, switching from butter
or stick margarine to lower fat tub margarine, or choosing reduced-fat cheese
instead of full-fat cheese.
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This study was funded in part by a grant from the Office of Epidemiology and
Health Promotion of the West Virginia Bureau for Public Health. The authors
acknowledge George Kelley, DA, FACSM, and Ken Simon, EdD, for their review of
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Corresponding Author: Bill Reger-Nash, EdD, Associate Professor, West
Virginia University, Department of Community Medicine, One Medical Center Drive, Morgantown, WV
Telephone: 304-293-0763. E-mail: firstname.lastname@example.org.
Author Affiliations: Margo G. Wootan, DSc, Center for Science in the Public Interest, Washington, DC; Steve
Booth-Butterfield, EdD, Department of Community
Medicine, West Virginia University, Morgantown, WVa; Linda Cooper, MSW, LCSW,
Department of Community Medicine, West Virginia University,
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