Reviewer: 1
Comments to the Author
The study hypothesized that new packet warning labels that were novel or
contained the newest news for smokers would result in the greatest attention
to the pack warning labels and increase basic beliefs about smoking related
illnesses. It was also hypothesized that visceral images would have the
greatest impact. The authors also wanted to determine the effectiveness of
selected warning labels to influence consumer recall and overall awareness of
disease caused by smoking. Specific hypotheses were not given for these latter
purposes. The aim of the study is appropriate, but there are several details
the authors need to address before this manuscript is ready for publication.
Summary
1.
The sentence “This study explores their impact on smokers’ beliefs.” is
not adequate. Beliefs in what? Change in beliefs? In addition, a purpose of
this study is to evaluate whether visceral images would have the greatest
impact.
Response: This has been expanded to be explicit that it is exploring smokers’
beliefs about smoking-related illnesses. A further sentence has been added
explaining that the study examines the varying impact of different types of
warnings, and notably those with visceral images.
2.
The statement about recall being high is somewhat meaningless without
information on the timing of recall and the actual type of recall that was
being assessed.
Response: The timing and type of recall being assessed has been added.
3.
You say “three independent cross-sectional omnibus surveys” were
considered in the analysis, but the paper actually considered four years of
data. This is a big oversight.
Response: This typographical error has been remedied and the years of the
surveys have been added.
4.
To say that “some have greater impact than others,” is too vague.
Response: the details of those with greatest impact have been added to the
subsequent sentence.
Introduction
5.
Page 2, lines 38-42, unclear and ambiguous.
Response: An extra sentence has been added to spell out the implications of
this sentence within the context of this study
6.
Page 2, line 44, the terms “awareness and knowledge” are used. Is this
supposed to be the same as belief (see Summary)?
Response: This is supposed to mean belief and hence the term “belief” has been
substituted.
7.
Page 7, line 4, the term “basic knowledge and beliefs” is used. Later
they refer to “awareness of health effects” and earlier “awareness and
knowledge” or just “beliefs” were used. This change in terms is confusing.
Response: All these instances of changing terminology have been removed and
the term “belief” is used universally.
8.
The hypothesis is that novel or new information about smoking will
result in the greatest attention to the pack warnings. What is new or novel to
one person may not be to another. How will this issue be addressed?
Response: A new paragraph explaining how newness or novelty is assessed has
been added to the end of the methods section. Newness or novelty is measured
at the population level. It may be the case that some smokers may have been
exposed to information in the past about messages that are classified here as
“new”, but this study is one of average population impact of population-based
communication.
9.
In general, the Introduction is a lengthy literature review that could
be shorted. Some of this information could fit better in the Discussion.
Response: A substantial section of the introduction has been removed.
Methods
10.
How do you know that the surveys were representative? Response rates
were 70% or less, and the response rate for 2008 was not even given. In
addition, on page 10 it says that only 9% of the respondents were male.
Response: Data were weighted by household size, age, gender and local
government area, so that estimates would reflect the South Australian
population.
The response rate for the 2008 study has been added.
49% of the respondents were male. This typographical error has been fixed.
New analyses have been undertaken and included to look for biases between
samples
11.
The Statistical Analysis section is not adequate. What statistical
analyses will be performed and was SUDDAN used to take into account the
complex sampling scheme?
Response: The statistical analyses were originally done using SPSS. They have
now been completely redone using STATA v10.0. Like SUDAAN, STATA provides
survey estimating tools which account for this survey design. The survey
estimating tools adjust the standard errors to account for the design which
involved clustering by Australian Census District, stratification
(metropolitan vs rural) and data that are weighted to the population. Interyear and intra-year differences between proportions were analysed using
Pearson chi-square statistics which are then converted in to F-statistics to
account for survey design.
Results
12.
Data on 2008 were reported, but thus far, nothing is mentioned about
there being 2008 data (i.e., in the Summary and Methods). Also, does paragraph
1 represent the smoking population?
Response: Information about the 2008 sample has been added to the Summary and
the Methods.
Paragraph 1 represents the South Australian population as a whole. A phrase
has been added to make this more explicit.
13.
Paragraph 1. In the 2005 survey, only 9% of the total population
sampled was male. Also, about 16% of the total population was classified as
smokers. Representation is an issue and generalizability of the results
problematic for this year.
Response: In 2005, 49% of the population was male; this was a typographical
error which has been fixed.
In 2005, 18.7% were smokers - with 16.5% smoking manufactured cigarettes. The
proportion of manufactured cigarettes is not significantly different to the
proportion of smokers of manufactured cigarettes in the following years.
Discussion
14.
Probably the most convincing argument that the graphic warnings were
effective is that recognition of cigarette packages as sources of anti-smoking
ads doubled with the introduction of the new warnings. Also, control groups
not used in the campaign experienced little change with each year. However,
not all graphic warnings experienced a dramatic increase in recall or
awareness. The study recognizes the difference, and hypothesizes as to whether
or not differences in the individual advertisements are the cause, but the
data does not address this. The claim that graphic warnings are effective in
increasing the awareness of adverse health effects is a fairly liberal
interpretation. Awareness could have increased in certain areas because of
natural interest or concern in the subject matter.
Response: In the first paragraph of the discussion, the phrase “contributed
directly to increased awareness” has been changed to “coincided with increased
awareness”. Other sources of increased awareness and chance are now
acknowledged in the discussion as potential other causes before making the
case (using the arguments that the reviewer notes).
Reviewer: 2
Comments to the Author
This is a timely study of graphic warning messages on cigarette packaging,
useful to jurisdictions considering such legislation. However, it also
evidences the need to keep messaging fresh, if the impact is to be maintained
over time. Overall, the paper is well presented and the argument well made. It
is solidly situated within existing cross-disciplinary literature and
international policy on tobacco control, and is relevant to researchers and
policy-makers.
My main issue is with the methods section. This section feels less assured
than the rest: for example, the opening line states that data were collected
from "independent cross-sectional surveys", but surely they are linked in some
way and, in the context of this study, should be considered a series?
Otherwise, this seems to contradict the insistence (elsewhere) that knowledge
and beliefs are being studied "over time" (and if they're to support the
"cause and effect" statement page 13, line 40-42). Is this a separate survey,
or are you using the data from ABS? The former, I'm sure, but a little more
clarity would help. And on page 8, line 6, what sort of interviews?
Structured, semi-structured? Also, whilst I may have missed this, where (page
8, line 12/13) does this Sth Australian Health Omnibus Survey come from, and
what's its relationship to this study and to the sampling just described? This
part of the section seems in all to be rather glossed over, and if we're to
trust the rest, I'd like to feel a little more secure that it's a study based
on sound research methods.
Response:
Several minor changes have been made to the methods section to try to be
clearer about the tool (the South Australian Health Omnibus Surveys) and its
methodology.
The data were collected in the South Australian Health Omnibus Survey. The
surveys are connected via their shared methodology, but each year an
independent sample on the order of 3000 participants is drawn from a
population of 1.5m.
Changes “over time” refer to changes in the South Australian population,
measured through cross-sectional surveys, not changes in a cohort.
Significance testing was done for independent samples.
A clarifying phrase about the sample/methodology has been added to the
paragraph containing the “cause and effect” statement on (former page 13,
lines 40-42).
Interviews were structured – this has been noted in the Methods-sample
section.
Page 8, lines 40-42 - What about smokers of hand-rolled cigarettes? Any?
Response: There were smokers of loose tobacco; smokers of hand-rolled
cigarettes and also pipes make up the difference between all smokers and
smokers of manufactured cigarettes. These smokers are not the subject of the
current study because the graphic warning labels legislation applied
differently to loose tobacco and manufactured cigarettes. Smokers of loose
tobacco were too few in number to allow any meaningful analyses.
Page 10, line 10: Query on the 9% male figure - seems very low, so is this
right? And, although you say these data reflect Sth A population, you offer no
comparisons by which to judge that statement.
Response: 49% of the sample was male. This typographical error has been fixed.
As noted in the Methods-Sample section, data in the South Australian Health
Omnibus Survey are weighted to reflect the South Australian population.
Finally, some additional detailed comments on the text follow - most are
hardly vital, but they may help clarification and ease of reading?
Page 4, line 28: "The authors" I assume refers to Borland et al, but could be
mistaken for referring back, comparatively, to this paper's authors?
Response: “The authors” has been replaced with Borland et al (2009)
Page 6, line 1: Is "for example" right? The example that follows appears to
refer to a previously unseen image, rather than used in previous social
marketing campaigns.
Response: This example is right, but the term “others have not” has been added
to the end of both the previous sentences for clarity.
Page 6, after "insert table 1 here": There may be some benefit in clarifying
the references to "new". Do you mean new as in new legislation on graphic
warnings, or new as in previously unseen images (as opposed to seen as part of
social marketing campaigns)?
Response: We mean new system of graphic warnings. A clarifying phrase has been
added.
Page 12, line 26: "Female smokers were also MORE likely..?"
Response: Done
Page 12, line 32/33: "No significant differences in recall..." yet you've just
said in previous paragraphs that there were differences. Is there a some
element missing in this sentence - diffs between what and what?
Response: This statement is about the lack of differences across sub-groups. A
clarifying phrase has been added.