PONE-D-23-09747Seatbelts and Raincoats, or Banks and Castles: Investigating the Impact of Vaccine MetaphorsPLOS ONE

Dear Dr. Flusberg,

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Reviewers' comments:

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Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: This manuscript is a well-written research study assessing vaccine attitudes of study participants following review and rating of metaphorical and literal responses to 5 common vaccine questions. There are some concerns regarding interpretation of the study findings that should be addressed prior to publication of this manuscript.

Major concerns:

1) Regarding section ‘3.2. Explicit ratings of the health messages (page 19 starting at line 333)’

a. Only significant differences are reported of participant ratings of how understandable, informative, or persuasive the metaphor or literal response is. A table summarizing all ratings data (understandable, informative, persuasive) and p-values for each of the 5 questions is much needed in order to be able to interpret the study findings.

b. Within this section, a broad conclusion is made that metaphorical messages are similar to literal messages, even though there is data indicating significant differences between metaphor and literal ratings. Page 19, line 339-343: The authors state, “These results indicate that people’s explicit judgments about the efficacy of the messages were roughly equivalent for all the messages targeting a given question, with a few minor exceptions. In other words, participants tended to perceive metaphor-framed messages as similar in terms of effectiveness when compared to comparable literal descriptions that do not include an extended explanatory metaphor.” It is not appropriate to refer to the significant differences found for question 1 and 5 as “similar” with “a few minor exceptions.” Given that the statistical differences are unique to each of the 5 questions that address different aspects of vaccine hesitancy, they should be interpreted separately, and these sentences should be revised.

c. The interpretation of the ratings of the 5 questions is presented as a conclusion in the abstract. Last sentence of abstract and page 35, line 677: “(2) Metaphors neither enhance nor reduce this effect relative to comparable literal passages.” Given the significant differences in ratings between the metaphor and literal messages, this conclusion is incorrect and warrants revision in line with the suggested revisions to section 3.2.

2) In this study, the authors investigated the impact of explanatory metaphors on vaccine attitudes assessed by a Vaccine Attitude Measures tool. A general conclusion was made that “metaphors are comparable to literal passages.” Their conclusion is contradictory to other studies that have shown positive correlations between patient receipt of a vaccine following a conversation with a physician who used a metaphor. This difference in study outcomes was never addressed in the publication and warrants a brief discussion.

Reviewer #2: I enjoyed this article and learned a lot from the authors’ careful study design and relevant findings. I think that this study would be of great interest to PLOS ONE readers, and I hope to see it published. The study was well designed, and I was especially interested in the original part of the study design that asked participants to “explain it to a friend” and answer vaccine-related questions in their own words. The findings are useful in contributing to a better understanding of how audiences and readers engage different types of vaccine-related information and how information and beliefs and decisions influence one another or not.

As I wrote above, I was most interested in the findings related to the authors’ method of asking participants to then answer a similar question as if it were posed by a friend. This participatory design -esque angle to vaccine and other forms of public health communication is original and exciting. I was very interested to learn about if and how participants used the metaphors that had just been modeled for them, and I wanted to read more about the ways that participants, when asked to take the reigns and answer this question for a hypothetical friend, improvised their own forms of vaccine communication. Thinking about Covid vaccination learnings, we learned that one of the biggest indicators that someone would be vaccinated against Covid was how many people they knew who were vaccinated. This correlation suggests that people are influenced a lot by those around them and suggests that lay vaccine communicators might have a lot to teach us about vaccination communication! I would look forward to reading an article about these findings and their implications.

I did have a few smaller suggestions that I think would help the article (1) better engage with vaccine-related scholarship and (2) clear up a few confusions I had about the study’s methods.

LITERATURE REVIEW

This comment isn’t one that I think absolutely needs to be addressed, but I did want to note that I wished the authors had addressed the growing body of work that investigates why people believe the things they believe about vaccines - i.e., the people the research team is trying and persuade with these metaphors.

I was wary that the authors avoided any reference to scholarship in the social sciences and humanities that has examined how people come to their vaccine beliefs and has largely concluded that deficit-based messaging approaches to vaccine communication and persuasion don’t work very well. Research shows us that, in short, the assumption that people are vaccine hesitant because of ignorance or misinformation and that their beliefs can be “corrected” by delivering persuasive and accurate information is limited. Instead, vaccine beliefs are complicated, fluid, and inextricable from their specific, social situations and histories. Changing vaccine hesitancy involves building trusted, long-term relationships with individuals and communities, not necessarily trying to package the right message and find the right messenger. Here I’m thinking of work by Bernice Hausman, Elena Conis, Nicole Charles, JEnnifer Reich, Maya Goldenberg, Heidi Lawrence, Melissa Leach & James Fairhead, Clare Decoteau, and Andrea Kitta.

I’ll add that this broader more contextualized approach to vaccine hesitancy as a complex social problem rather than a problem of individuals who believe the wrong things came, briefly, into mainstream vaccine discourse during the phased distribution of Covid vaccines, a time when there was a lot of talk about how and why, for example, people without health insurance might be vaccine hesitant because they don’t trust the systems that produce vaccines to look out for them (and not because they don’t understand or trust the vaccine, specifically), or why Americans of color would be skeptical of the US healthcare system and hold off on signing up for a new vaccine.

This isn’t to say that studies focused on questions about effective messaging don’t have a place – as I’ve written in the rest of the review, I think there’s so much of value in this study – but especially in a study that is attuned to audience and learning how targeted audience members make sense of and are or are not changed by a message, I would love to see, in the literature review sections, acknowledgement of the humanistic and social science work out there that is investigating and producing really important findings about how people come to their health beliefs and decisions.

METHODS

Recruitment

I wanted to know more about the limitations and reasons for using Amazon’s mTurk as a recruitment tool. Obviously it’s easy to recruit participants through this tool, but are there other, more research-driven reasons the authors chose to use mTurk?

In particular, I think the authors should discuss to what extent mTurk participants are a representative group to draw conclusions about general vaccination feelings, beliefs, and persuade-ability. I’m thinking again of all of the great social sciences and humanistic work that argues that real and effective vaccine communication must be built in relationships over time. That is, communicating scientific facts to people–even in culturally specific and artful ways–doesn’t work because this kind of generalized, mass communication rarely addresses people’s actual concerns, which are grounded in their lives, experiences, personal and collective histories, and social networks. So vaccine communication needs to be localized, iterative, and built into broader networks of relationships and trust. By asking mTurk anonymous participants who are likely churning through digital tasks one after another to share a bit about their responses to vaccine messages, the authors are not aligning themselves with this body of research. So I wondered what scholarship the authors are drawing on to endorse learning about vaccine beliefs and changes in belief in this way, that is, in a way that asks people to type a bit about their vaccine decisions made hypothetically, abstracted from all context, and only in hypothetical terms?

The research design – asking people to take assessments about conspiracy beliefs, vaccine beliefs, etc., and using an attention check to select participants more likely to actually read the prompts – all looked great. But I wanted to better understand how, in light of so much research pointing to vaccine decision-making as complex, situational, and tied to specific, local contexts, this method is useful to generate knowledge that *actually* captures how people are making vaccine decisions.

I also think the Methods section should address how participants were compensated.

Study design

I wondered about the authors’ choice to use similar metaphors to answer the question “How do vaccines work?” Based on existing scholarship on vaccines and metaphors, both of these metaphors would fall into a category of older commonplace metaphors about bodies, vaccines, and disease–metaphors that see each body as a sealed-off, fortress-like entity that defends itself against outside germs. By contrast, a more contemporary metaphor by which many people understand the body and immunity is that of a complex system (flexible immunity) – the body constantly adapts to its environment and grows stronger through encounters with pathogens and other things, like dirt. (Emily Martin’s work on immunity and immune systems metaphors is foundational here, but other scholarship on vaccination and metaphors has taken up and extended this argument. So, it seems like both of the metaphors here rely on the older model of the body - a discrete self that must be defended - rather than this flexible immunity model. I wonder if the authors can speak to this decision?

I wondered why the authors didn’t consider race as a demographic feature that influences vaccine decision making and trust in institutions (p. 20, lines 356 - 359)?

On p 15 lines 247-8, the authors write “After reading one of the three explanations associated with a particular question,participants were asked to consider how the general public would react to the message and to keep this in mind while responding to four questions.” I didn’t understand why the authors asked the participants to imagine how a general public audience would respond to the persuasive messaging. Isn’t the goal of the study to track how individual participants respond to the messaging? And to see how individuals respond to and are affected by the messages? It seems the participants should be reporting on their own impressions–how easy each participant found a passage to understand, how informative each participant found a passage–and not trying to speak for an imagined, general public audience.

Not a point that needs to be addressed, but a possibly generative question I had while reading:

I was interested in how the results about which metaphors were effective and ineffective might reveal more about public understandings of public health more so than the effectiveness of individual metaphors. For example, the metaphors that rely on individualist ideas of health (i.e., do things that maximize your own personal health and minimize risks to your own persona health) were the more clear, salient, and effective metaphors (e.g., Bank metaphor, Castle metaphor, Raincoat metaphor) And the metaphors that asked audiences to think about health as an interdependent, community state, one in which we should make decisions toward a greater social good fell flat (the war metaphor). Do these findings suggest that specific metaphors themselves were more or less clear or do they suggest that metaphors, arguments, policies, etc that align with individualist notions of health make more sense than metaphors, arguments, polities, etc that align with collective approaches to health?

Sentence-level points

Is there a reason to use the word “Interestingly” on p 3 line 53? And “presciently”? (Global vaccine hesitancy was already a big problem in 2019, so more accurate than prescient, I would say).

Typo on p 4 line 87

I had trouble following the last 2 analytical sentences of the section “1.2. Explanatory metaphors in vaccine discourse” (on p. 8, lines 150 -6)

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Reviewer #1: No

Reviewer #2: Yes: Kari Campeau

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PONE-D-23-09747R1Seatbelts and raincoats, or banks and castles: Investigating the impact of vaccine metaphorsPLOS ONE

Dear Dr. Flusberg,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Thank you for improving the manuscript. In this round, two additional reviewers provided minor comments that should be fixed. On top of that, my comments are: (1) please use the singular form “between-subject” instead of “between-subjects,” (2) please provide p-values or at least the indication of the statistical significance of the differences in Table 4 (that was also asked by one of the Reviewers in the previous round), (3) when mentioning one-way ANOVA, please explicitly state what the factor (independent variable) is, (4) why you do not provide comparisons between two conditions that constitute your experimental design (i.e., metaphor vs. literal), as you declared (rows 188-189), (5) when reporting p-values on p. 20, please also report the means and test statistics.

Please submit your revised manuscript by Oct 01 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
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• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Wojciech Trzebiński, Ph.D.

Academic Editor

PLOS ONE

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Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

Reviewer #4: (No Response)

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: (No Response)

Reviewer #3: As a "second-round" reviewer I would like to acknowledge that the authors answered to the concerns and question raised by previous reviewers and add that: 1) (lines 156-157) literature on the impact of metaphorical framing on vaccine attitudes is not limited to Scherer and colleagues 2015 (see Ervas et al. 2022); 2) (question 4; metaphor 2 WAR) "With certain viruses, some people who get infected can experience" --> the word "can" is added, when compared to the other texts, with no apparent reason. In general, the texts (especially in the "literal version") are not well-balanced: the literal version is always shorter than the other versions and this might influence the ease and times for comprehension.

Reviewer #4: This paper describes a very interesting study with a sound methodology and relevant findings for the examined field (which also provide useful insights into aspects of metaphor use that go beyond the main purpose of the study itself). For instance, some inputs are given as to which specific aspects of vaccination can be successfully explained through metaphor use (e.g., natural immunity vs vaccine immunity). Furthermore, the section with the free-text answers (with some metaphors used incorrectly but with the same conceptual mapping presented in the explanation stimulus, others used correctly but in the attempt to refute the statements presented in the explanation stimulus, others invented by respondents) is also an interesting starting point for future research.

The study limitations (e.g., resorting to only a selection of metaphors available in vaccine campaigns) and previous reviews’ comments (like some remarks concerning methodology, like why respondents needed to state how they thought a general audience would react to certain messages rather than express their own opinion directly – to avoid some sort of “self-censorship” due to the stigmatization of vaccine aversion and hesitancy in an emotive and politicized historical moment like the one right after the coronavirus pandemic) seem to have been addressed properly.

The conclusion is that it is deemed to be highly advisable to publish this paper.

Some (minor) remarks and/or suggestions that may help further improve the paper are the following:

ABSTRACT:

I would mention the denomination “literal responses” a line before. The current formulation may be initially confusing: while reading the abstract, my first thought was that the study was going to examine extended metaphors and non-extended ones (as defined later in the paper - in p. 8, line 167 - “one-off” metaphors). A possible solution would be: “We created three response passages for each question: two included extended explanatory metaphors and one contained a literal response, with no explanatory metaphors”).

MAIN TEXT:

1) In the theoretical framework, when I read the section about extended explanatory metaphors (and their opposition to “one-off” metaphors) I thought about the frequent term “metaphor(ical) scenario” (as in Musolff 2006 or 2016*) with the “mininarratives”. It could be useful to add this terminology in the beginning to clarify what is meant in the text with “extended metaphors”. In case there is no full equivalence between this term and term “extended metaphors” as intended in the study, this could also be explained and motivated.

In addition, the term “metaphorical scenario” does indeed occur randomly in the paper (line 559, with respect to the Video Game metaphor, and line 574, with respect to the Raincoat metaphor), which further convinced me it could be useful to add it in the beginning, too.

N.B.: “scenario” also occurs a third time in line 583, in the segment “in the answers to the friend scenario”. As “scenario” is a technical term in metaphor studies, I would reformulate this part to avoid possible confusion.

2) I find that there are some similarities between some of the metaphors chosen for the study. More specifically, I feel that the Castle metaphor is a subtype of War metaphors (of course, with a different focus, but the mention of words like “invaders”, “defence” etc. seems to support this theory). I find this aspect important for several reasons. Firstly, on the basis of what is stated in the Linguistic Analysis at page 27: “[…] This is consistent with the finding that the War metaphor was perceived as particularly ineffective, as also shown in the ratings data described earlier. This is a particularly interesting finding given the prevalence of war messaging in vaccine discourse, particularly early on in the pandemic”. If the (more effective, “successful”) Castle metaphor is also regarded as a subtype of War metaphors, this once again shows that (although controversial!) war metaphors are quite effective, and this sentence should be modified accordingly.

To differentiate between these two metaphors, maybe a different (more specific, as occurs with Castle) label could be proposed for what is now called War metaphor in the paper survey (in Question 4, Metaphor 2), like Army Enrolment, Army Enlistment, or Mobilization.

Considering the Castle and Army Enrolment metaphors as subtypes belonging to the same source domain may also have an impact on the paper in other ways: as stated at page 24, some metaphors may be especially effective to communicate about some particular aspects of a phenomenon (e.g., Pilots and Fire Drills and a particular issue of natural immunity). If the categorization I put forward is implemented, the importance of choosing the right connection between a specific source and target (sub)domain is also better highlighted. So maybe war metaphors are effective in showing how vaccines work but not as effective in explaining the concept of herd immunity. This different effectiveness can also be explained through one of the variables reported in Table 1 at page 5 (army mobilization, unlike castle defence systems, is not very straightforward to many people! I also found this extended explanatory metaphor quite hard to follow as I first read it).

3) I think that the use of the rhetorical question “Would you rather wear a raincoat or walk around unprotected during a thunderstorm?” at page 31 should be highlighted, as it shows some sort of emotional involvement on part of the participant, which proves that this metaphor is effective.

TYPOS:

p. 19, line 326: five response questions (I guess!)

p. 20, line 359: explicit

p. 25, line 452: abstract

p. 29, line 29: “[…] question asked was “How do vaccines work?”. The […]

p. 31, line 577: “raincoat even if” (or, if it was a mistake made by the participant, add [sic]!)

p. 32, line 597: missing full stop before “finally”

p. 32, line 604: (92106; 100% re-user) --> I think this parenthesis was not meant to be here, maybe it was a note/reference meant only for the authors which “slipped in” during writing. If this is not the case, it is not clear what this number refers to.

p. 36, line 688: there seems to be a missing space before “relatedly”

p. 37, line 711: after both occurrences of e.g. the comma is underlined

SOME POTENTIAL TYPOS/POINTS WITH POTENTIAL STYLISTIC IMPROVEMENTS:

Consider that I am not a native speaker of English, so these are some points that can be ignored by the authors if necessary:

p. 4, line 74: The seminal work […]?

p. 31, line 591: metaphor use? Or used?

p. 36, line 697: willingness/ the willingness to get vaccinated?

OTHER TYPOGRAPHICAL INDICATIONS:

I recommend being more typographically consistent in the way metaphors are reported. For instance, in the theoretical framework some metaphors are written in italics (beast, riot etc., line 158). In line 697, the same metaphors have a standard font, with no italics. In the introduction, some metaphors are reported between inverted commas (e.g., the “Cake” metaphor, line 168), but then they have a standard font in other parts of the text (e.g., the Bank or Castle metaphor, line 362). Of course, small capitals can be kept as a way to refer to conceptualizations and domains (as occurs in the introduction at page 4, for instance).

Line 662: seven in digits, maybe?

Use of hyphens: in some cases (like page 8, line 162-3, or 184-5) hyphens are longer and words are not separated by a space. In other cases, like at page 34 (line 658) the hyphen is shorter and there is a space that separates it from the words.

Pag. 18, line 313: maybe here the usual indication “[…]” should be used instead of the three dots?

*Musolff A. (2006) “Metaphor scenarios in public discourse”, Metaphor and Symbol, 21:1, pp. 23-38.

Musolff A. (2016) Political metaphor analysis: Discourse and scenarios, Bloomsbury Academic.

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Reviewer #1: Yes: Amanda J Chase

Reviewer #3: No

Reviewer #4: No

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PONE-D-23-09747R2Seatbelts and raincoats, or banks and castles: Investigating the impact of vaccine metaphorsPLOS ONE

Dear Dr. Flusberg,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Dec 02 2023 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

Wojciech Trzebiński, Ph.D.

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Additional Editor Comments:

 I appreciate your improvements, and the reviewers accept your revised manuscript. However, I have one more crucial doubt that needs to be addressed before the acceptance. Namely, one may understand from your Abstract that the only positive result you have consistently reached is that “participants in the metaphor condition provided longer free-response answers to the question posed by a hypothetical friend” (rows 39-41). If so, it is crucial to provide some argument that this difference is statistically significant. In Table 5, you report the “cumulative” word count. If it is a sum of words used by all participants in particular conditions, it depends on the sample sizes. So, it would probably be necessary to calculate the means of the word count per condition. Then, you should compare the means between conditions to check the statistical significance.

Please also double-check the manuscript for typos (e.g., row 566). 

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #3: All comments have been addressed

Reviewer #4: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #3: Yes

Reviewer #4: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #3: Yes

Reviewer #4: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #3: Yes

Reviewer #4: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #3: Yes

Reviewer #4: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: The authors addressed all my questions/concerns. Thanks for the opportunity to read this piece of reasearch.

Reviewer #4: At this stage of review, I only want to point out a few typos/stylistic suggestions:

War mobilization in italics, lines 526-7

line 632: and not capitalized

line 619-620: and not capitalized twice

We return to this finding (lines 470, 544): I think this could be formulated in a better way stylistically, like "This finding will be further discussed/discussed in greater detail ...etc. "

But see 37 (line 670): I find this could also be expressed in a better way

Posttest is sometimes written with an hyphen, sometimes without it; I do not understand if there is a reason to it

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Reviewer #3: No

Reviewer #4: No

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[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Seatbelts and raincoats, or banks and castles: Investigating the impact of vaccine metaphors

PONE-D-23-09747R3

Dear Dr. Flusberg,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Wojciech Trzebiński, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Thank you for further improving your manuscript, especially in terms of statistical analysis. 

Minor issue to be fixed with the editorial team: at the oend of line 565, there is still an unnecessary quotation mark to be removed.

Reviewers' comments: