PONE-D-21-12657

The institutional origins of vaccines distrust: Evidence from former-communist countries

PLOS ONE

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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: Partly

Reviewer #2: Partly

Reviewer #3: Yes

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

Reviewer #1: Yes

Reviewer #2: I Don't Know

Reviewer #3: 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

Reviewer #3: Yes

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Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: 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: In the current manuscript, entitled “The institutional origins of vaccines distrust: Evidence from former-communist countries”, the authors show the association between being exposed to Soviet communism affect trust in vaccines, which is explained by weaker institutional and governmental trust. I enjoyed reading the manuscript as it was clearly written, and deals with what I think is an extremely important topic, namely, vaccine hesitancy. However, I believe that there are two major issues that should be addressed. I list these below, and I hope that the author would find them useful.

1. I think that some more elaboration on why exposure to Soviet communism would be relevant to vaccine hesitancy is warranted. Is it something about the history of those countries? Is it something about the ideology? Culture? For example, recent research by Maaravi and colleagues shows the relationship between individualism / collectivism and COVID-19 spread (which I can only assume is correlated with exposure to Soviet communism, although they show a trend that to some extent is opposite to the current research results). Other unpublished research by Adam-Troian and colleagues (see here https://psyarxiv.com/nzg7x) examines the association between collectivism, masculinity (controlling for other relevant variables such as Human Development Index) to belief in conspiracy theories (which was linked to institutional trust and vaccine hesitancy). All of this to say that I think that some more precision about what is it exactly in exposure to Soviet communism that leads to vaccine hesitancy and lower levels of institutional and governmental trust is important.

2. I believe that in order for the analysis to be persuasive it has to control for other relevant variables that are related to institutional, governmental and vaccine trust (both on the country and individual levels). Both the work by Adam-Troian et al. and Maaravi et al. I mentioned above control for some relevant such measures.

3. The results on “psychological mechanisms” go some way to address my first comment, but I think that there’s still a need to further explain what is it in the exposure to Soviet communism that drives these effects. Is it something about the type of regime? Is it something about the process in which these regimes collapsed and what happened since that broke individuals’ trust? Is the trend only relevant to Soviet communism? Why would that be the case? Is it because it collapsed? Is it just because vaccination was obligatory in the former Soviet Union? In other words, I think that more is needed to be done in order to explain whether the trends the authors report in the paper are specific to Soviet communism, and if so, why? Or whether it is something that has to do with regime changes or authoritarian regimes, etc.

4. As a minor comment, I think that it would be good to label the y-axis in the figures. I am not sure it is clear.

5. As another minor comment, maybe some more explanation about how exposure to communism was computed in the model. The authors indicate that it was measured in two different ways, but then it was less clear to me how these two different ways were combined.

Reviewer #2: When I saw the Asbtract for this paper, I was very excited. I undertake sociological research on 'trust in vaccinations', so to see a potential paper exploring the impact of communism on trust in vaccinations was exciting. The authors use exisitng data from the Wellcome Global Monitor (which is fine) and undertake some statistical analysis (which I am not equipped to review). The Introduction is too broad, and does not adequately present and critique global literature on 'trust in vaccinations' and needs to enagge much more deeply with the sociology of trust. There is a huge litertaure on trust in governments, medical institutions, pharamceutical industries etc - very little if any of this has been engaged with. The authors need to be able to set their study and findings within these literatures - so they can identify 'what we already know' and 'what's new'. On lines 24-26, there's a referencing problem which goes throughout the paper (the first references are 6 and 1? In the Discussion, the authors could/should engage with sociologists who have explored how trust differs between different societies - for example, Fukuyama explored trust in different societal structures. In the Discussion, the parapgraph on lines 151-161 does not seem to be relevant at all - the authors have introduced COVID-19 context, but the Wellcome data predated COVID-19.

Reviewer #3: Title: The institutional origin of vaccine distrust: Evidence from former-communist countries

Journal: Plos One

The article is a study of vaccine distrust in former-communist countries. Based on an analysis of data from the Welcome Global Monitor (WGM) database, the authors seek to show that exposure to communist regimes play an important role in distrust in public institutions that leads to vaccine hesitancy. Considering the scale of the challenge associated with vaccine hesitancy, especially during a pandemic, this article’s contributions to policy framing and guidelines are timely and necessary.

While the article does offer an important and timely exploration of vaccine hesitancy in former-communist countries, there is still some work to be done in establishing a coherent narrative, and tightening the arguments by addressing not only the results of the analysis but also more of the literature on trust, hesitancy and health policy. Addressing these issues (and a few other minor comments) will strengthen the arguments made in the article. More specific comments follow:

1. The authors provide very clear and admirable inclusion/exclusion criteria for which they should be congratulated. However, the grouping of former-communist counties and the assumption that all communist experiences are similar might be problematic. While it might be difficult to account for the broad variety of experiences based on the available database, I suggest the authors address this methodological difficulty.

2. On page 3, the authors claim that the “military-like organizations and its compulsory participation lead to a questioning of such campaigns after transition”. While these claims might be intuitive to scholars of former-communist health systems, many of the journal’s readers may not be acquainted with this argument. Therefore, it would be helpful to add sources baking the claim.

3. In the Data section (page 4) the authors address the length of the influence of life under communist regimes. If possible, it would be helpful to address inter-generational effects as well.

4. In their analysis of Underlying mechanisms (page 6) the authors claim that trust has deteriorated. This framing assumes that trust existed in the past, however it’s unclear in the text if this is indeed the case.

5. The article has the potential to contribute greatly to the discussion on trust in state institutions and vaccine hesitancy. However, in order to do so more attention is needed to the already broad body of knowledge on the issue. The theorizing of trust and hesitancy appears only in the discussion, and it would be helpful to address it earlier in the article.

6. Along the same line, a clearly framed discussion on trust in institutions and hesitancy would help the authors take their place in a very active field (and explain how is this case different from other cases).

7. I suggest the authors look at Heidi Larson’s book Stuck (2020) on vaccine rumors. While other works by Larson are cited, this might be an interesting read in terms of framing the context.

8. On page 8, the authors shift to COVID-19. While this is obviously a burning issue (and of relevance to the article) it is not necessarily clear how a study conducted pre-COVID-19 relates to the matter at hand. A clearer connection should be made in order for this important section to be a better fit.

9. The authors end with a very interesting note on the use of compulsory mechanisms. I encourage the authors to be even bolder in their conclusions, and odd their recommendations.

10. As someone who is interested in trust in the state and health policy I have truly enjoyed reading this article. I thank the authors for their analysis.

For the reasons mentioned above I recommend accepting this article for publication pending revisions. I look forward to seeing this important work in print.

Kind regards

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Reviewer #1: No

Reviewer #2: No

Reviewer #3: Yes: Anat Rosenthal

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PONE-D-21-12657R1The institutional origins of vaccines distrust: Evidence from former-communist countriesPLOS ONE

Dear Dr. Nicińska,

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 Feb 19 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 you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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,

Jerg Gutmann

Academic Editor

PLOS ONE

Additional Editor Comments:

I have very recently taken over this submission as the academic editor. Previous reviewers have been approached, but not all of them have been able or willing to review the revised version of the article. The article has, thus, also been sent to one new reviewer who is an expert in the field and he or she very swiftly produced a review of the revised and resubmitted version of the article.

Two previous reviewers are satisfied with how their comments have been implemented. The new reviewer suggests a number of revisions before the article can be considered for publication. I agree with the reviewer's judgment that the authors currently seem to be leaving out essential information for being able to evaluate their empirical analysis. Also, some decisions need to be (better) justified. I would, thus, urge the authors to take the new reviewer's comments very seriously in revising the article. Should you be willing to revise the article based on these comments, the revised version would only be sent back to the new reviewer.

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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 #2: 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 #2: Yes

Reviewer #4: Partly

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

Reviewer #1: Yes

Reviewer #2: I Don't Know

Reviewer #4: No

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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 #2: 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 #2: 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 #2: The authors have adequately addressed my concerns from my original review. They have engaged with some of the sociology of trust and more empirical research around trust in vaccinations

Reviewer #4: Although I wasn’t involved in the previous review of the manuscript, I am familiar with the work from a preprint. I generally like the work, but I have a few points that I think are worth considering before acceptance. Some are minor, while others are more major.

In the abstract it states “… from a long list of world countries…”, but I think there is no need to be so vague. I’d recommend stating the exact number. Also in the abstract, there is causal language without any causal tests to justify it: “past exposure to Soviet communism reduces trust in vaccinations”. I think based on the correlational nature of the data, a more accurate statement would be something like “past exposure to Soviet communism is associated with reduced trust in vaccinations”. I would tone back any causal language that occurs throughout the manuscript to be more inline with the nature of the data.

In the introduction, it was mentioned that experiencing mass vaccinations in Soviet countries might lead to vaccine distrust. This is perhaps true, but voluntary vaccination rates for the flu are considerably higher in former communist East Germany compared to West Germany (Rehmet et al., 2002), which might suggest it is, at least, more complicated.

Based on the argument presented in the manuscript, I was partly expecting a mediational analysis of the effect of communism on vaccination hesitancy. Namely, that it is mediated by lack of (some form of) trust. If such an analysis isn’t done, then talks about mechanisms should be more speculative. Recently published work that found trust in government mediated the association between former communist federal states and COVID-19 vaccination rates within Germany (at the state level rather than individual level; Martens, 2022). This is a highly relevant article for the current work.

I believe the results are presented in a more confusing manner than they need be, and they generally lack detail. What analyses were specifically run is not clearly presented. I assume these are a series of regressions, but then what are the exact results (e.g., B, CI, etc.)? I see figures, but tables with specific values would provide more information and aid in reproducing the effects and in any metanalysis down the road, etc. Consequently, although I generally like what the manuscript attempts to do, I feel unable to fully judge it because I am not confident in precisely what analyses were run or what was found.

I think there should be more mention of religion or spirituality since we know it influences vaccination skepticism (e.g., Rutjens et al., 2021) as well as COVID-19 vaccination rates (Martens & Rutjens, 2022). Given that the Soviet Bloc is predominantly Orthodox Christian, how can we be sure this isn’t a religion effect rather than a Soviet communism effect? I don’t actually think it is since Martens (2022) found a communist effect in Asia, but I believe this should at least be addressed in text as it is a likely contributing factor to vaccination hesitancy. Perhaps as a future direction.

What are the hypotheses precisely? In the introduction (sentences 5-9) it states that the paper examines the reaction to historical events (mass vaccination during Soviet times), weak trust in government and health system, suspicion of large business organizations (big pharma), and a reaction to egalitarian values of Soviet communism. Presumably how all of those are related to vaccine hesitancy (or vaccine trust as it is sometimes put). At other times the manuscript states it inquires about the effects of exposure to Soviet communism on trust in vaccines efficiency and safety (21-22), and whether communism explains different dimensions of vaccine trust (23-24). The first results presented give a breakdown of vaccine safety and efficiency (via a table) with some mention of communism. It next presents data to suggest an underlying mechanism (trust in government, doctors, etc.). From what I can tell, the section on underlying mechanisms is not actually testing underlying mechanisms, but rather an association consistent with the mechanism. Perhaps I’ve misinterpreted these results, but I believe that is partly part of the problem, since what was done is not clearly communicated. In addition, the distinction between intensive and extensive margin effects is interesting, but similar to above, it is difficult to follow what was precisely done here. What data/test actually supports that claim? The last part of the results is on robustness of the association. I see no data or results measuring mass vaccinations during Soviet times, suspicion about large businesses, or egalitarian values, so contrary to the introduction, these were not evaluated. They might be aspects that support your hypotheses (which I take to be that Soviet communism in particular leads to lack of trust in a variety of areas, which then leads to vaccine hesitancy), but they aren’t part of the data collection or analyses.

Generally speaking, I found the introduction and discussion to not be overly developed. I think sub-headings with clear points (perhaps framed around hypotheses) could help here. That might also help the results section (i.e., frame results more explicitly around hypotheses testing).

It isn’t clear to me why the focus is solely on Soviet communism. Is it because of mass vaccination efforts in Soviet communism countries that didn’t happen in Asian/African communist countries? Asian communism is associated with lower vaccinations rates for COVID-19 (Martens, 2022), so perhaps it isn’t something unique to Soviet communism. If it is something unique to Soviet communism then you would expect an effect with Soviet communism but not other forms of communism, but you can test this by including other forms of communism in the analyses. If running this test isn’t possible for some reason, then I’d like to see more of an expansion on justifying why Soviet regions are the focus.

Trust in vaccinations seems to be operationalized as both vaccine efficiency and safety. I’m not convinced that those are two measures of vaccine trust. Maybe they do (which would be good to hear justification for), but someone might have complete trust in taking a vaccine but think it is not efficient (e.g., it takes multiple injections for full immunity). Safety appears to be more directly about trust than efficiency, but neither are the most direct, which would be something like “I trust vaccines”, which unfortunately doesn’t appear to be part of the dataset. I’d recommend rethinking the label (hesitancy was used earlier in the paper, so might be used for consistency, but views/opinion could also work here. Skepticism is another possibility, and previous work that used the same data set called those variables skepticism; Martens & Rutjens, 2022) and/or justifying how those are actual measures of trust. I assume those two measures are highly correlated, which would be good to see since they are the main DVs. It might make sense to combine them into a scale which might help with any odd effects of any individual item, unless the authors are trying to make an argument more specifically about each aspect (efficiency and safety). I take it that this is more about hesitancy, so a scale might make sense here.

The authors state, “In our multivariate analysis” (138), but what type of multivariate analysis precisely? A few more details here would be quite useful. It would also be useful to put some statistics in text or at least a table with all the relevant values. Similarly, the authors state that the effect sizes depend on exposure to communism, but the min/max values here would be useful to know in text and also help with interpreting the data. More details are needed all around.

Table 1 is used to suggest that Soviet countries have lower vaccine efficiency and safety, but the countries are sorted by alphabetical order rather communism, so this pattern is difficult to see in the table. I’d recommend breaking it down with Soviet countries on one side and non-Soviet on the other so that the comparisons are much more apparent. Some descriptive statistics would also help here (Ms, SDs, etc.). The authors seem to have gone for a minimalistic presentation of the data, but the lack of details raises more questions that might easily be answered by including more details in text, in tables, etc.

Martens, JP (2022). Communism’s lasting effect? Former communist states and COVID-19 vaccinations. Cross-Cultural Research, https://doi.org/10.1177/10693971221134181

Martens, JP, & Rutjens, BT (2022). Spirituality and religiosity contribute to ongoing COVID-19 vaccination rates: comparing 195 regions around the world. Vaccine: X, https://doi.org/10.1016/j.jvacx.2022.100241

Rutjens, B. T., Sengupta, N., der Lee, R. van, van Koningsbruggen, G. M., Martens, J. P., Rabelo, A., & Sutton, R. M. (2022). Science Skepticism Across 24 Countries. Social Psychological and Personality Science, 13(1), 102–117. https://doi.org/10.1177/19485506211001329

Rehmet, S., Ammon, A., Pfaff, G., Bocter, N., & Petersen, L. R. (2002). Cross-Sectional study on influenza vaccination, Germany, 1999–2000. Emerging Infectious Diseases, 8(12), 1442–1447. https://doi.org/10.3201/eid0812.010497

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PONE-D-21-12657R2The institutional origins of vaccines distrust: Evidence from former-Soviet countriesPLOS ONE

Dear Dr. Nicińska,

Thank you for submitting your revised manuscript. Unfortunately, the reviewer who suggested a major revision of your manuscript was not available for private reasons to review your manuscript. Thus, I have checked the implementation of the suggestions myself and they appear convincing. Before we accept your manuscript for publication, I would only ask you to fix some minor mistakes in the manuscript:

- Your estimation equation suggests that year of birth fixed effects vary over time. That is not correct. These are individual specific attributes that do not vary over time. Please adjust the index in the equation - unless I am misinterpreting what you are doing.

- Figure 1: I assume that the color-categories are based on quartiles or quintiles? Please provide the information what logic the color coding is based on. Also, it does not seem to make sense that the white category refers to values from 0 to 0!? Are these missing values? Please check and correct if necessary. (I assume this must be a mistake).- Figure 5: Please use only standard-English terms to label your figures. You can also drop the labels on the vertical axes to be consistent.

- All figures and tables (including supplementary material): I would strongly suggest to consistently use the same number of digits after the decimal point - unless there are reasons to deviate. Anything else looks very unprofessional. Also, showing about 8 digits after the decimal point does not convey any meaningful or comprehensible information, so I would suggest to limit the number of digits to a reasonable amount while still being sufficiently precise.- You may also give the manuscript another read for grammar and other language mistakes. If you make any other changes to the manuscript, these should, however, be communicated.

Please submit your revised manuscript by Mar 25 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. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

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We look forward to receiving your revised manuscript.

Kind regards,

Jerg Gutmann

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.

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The institutional origins of vaccines distrust: Evidence from former-Soviet countries

PONE-D-21-12657R3

Dear Dr. Nicińska,

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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Kind regards,

Jerg Gutmann

Academic Editor

PLOS ONE

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