PONE-D-20-11961

Rapid Assessment of Psychological and Epidemiological Correlates of COVID-19 Concern, Financial Strain, and Health-Related Behavior Change in a Large Online Sample

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

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

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

Reviewer #1: I Don't Know

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?

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

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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 review is of a manuscript under consideration for publication in PLOS-One by Nelson et al., entitled “Rapid assessment of psychological and epidemiological correlates of COVID-19 concern, financial strain, and health-related behavior change in a large online sample.” The paper describes a cross-sectional study conducted by self-report of Americans during late March/early April 2020, during the coronavirus (COVID-19) pandemic. The authors conclude that mental health symptoms are more highly associated with COVID-19-related concern and quarantine behaviors and make leaps of interpretation regarding possible impacts on behavioral changes. The paper should benefit from rapid publication, due to the sensitivity of the timing of information related to the pandemic; however, the reviewer does find major concerns that must be addressed prior to publication. With that in mind, the reviewer wishes to stress that there are no “fatal flaw” concerns here; the listed problems should be able to be addressed without extensive additional work, and the length of the comments are primarily intended to make clear the reviewer’s thoughts.

Major comments:

1. The paper equates confirmed world and or country cases with objective risk, an oversimplification that leads to an overreach of conclusions and a possible misinterpretation of findings. The survey does not allow the authors, as far as the reviewer can tell, to measure household presence of, or caretaker responsibilities for, high risk individuals, a key factor that greatly modifies objective risk in this scenario and which affects a large number of individuals. Caretakers for, or individuals of, high risk must be more vigilant than the average person under normal circumstances and thus, were almost certainly more attuned to the danger of COVID-19 early in the pandemic. Additionally, it was known fairly early that age of over 60 or 65 increased risk, greatly widening the number of people falling into the high risk category and the number of people directly affected by the health of high-risk individuals. Indeed, the authors report that age is positively correlated with COVID-19 concern, making this scenario possible. The question is, are individuals affected by higher risk driving the findings relating to stringent quarantine behavior and or concern about the virus? The authors conclude that mental health symptoms (anxiety and depression) explain more variance in COVID-19 concern than objective risk, but using world/country case numbers to indicate objective risk is not an equivalent representation for a large number of people. The authors say their findings coincide with studies suggesting that emotional risk perceptions are stronger determinants of behavior change than objective risk. However, if their findings are driven by high risk-affected individuals, who are ostensibly at greater risk for infection, complications and death, this interpretation isn’t appropriate. If by late March/early April, the U.S. had still had a negligible number of cases, perhaps equating country cases to objective risk would be fine here, but that was not the case. The reviewer suggests a reconsideration of interpretations with this in mind. At the very least, there should be space dedicated to this possibility in the discussion and the authors’ longer-term follow up should explore this avenue. The authors should be careful to also change abstract and conclusion wording accordingly to best reflect their final interpretation.

2. The paper implies that correlation, or association, implies causation and without much discussion of other possibilities, they imply a direction of causation. Specifically, they say “These findings suggest that the propensity for worry and sadness is somewhat adaptive in the current environment…”, and suggest that fear and sadness are causing protective behaviors. Related to the reviewers concerns in the separate point above, it could be that individuals at high risk or with direct ties to or caretaking roles for high risk individuals (their children and/or parents) are experiencing mental health symptoms and are taking the virus more seriously due to their more prominent, objective risk. Likewise, the authors seem to favor that perhaps depressive symptoms are improving quarantine behavior, but another interpretation is that individuals under more stringent quarantine, for whatever reason, have increased symptoms of depression due to strain of isolation, including a lack of social interactions. The reviewer suggests that the authors think more carefully about the implications of their work; they may wish to keep some of their points about public education, but need to round those arguments out carefully and consider other implications their work may have and how that information could impact interventions for the public.

3. There are many spelling, grammatical, and other errors that should be corrected to meet the quality standards of the journal and to best convey the information.

a. Some examples:

i. “inflection” is found at least twice, instead of “infection”

ii. Case fatality rate (CFR) should be defined properly on Line 63. Later “CFR” is used alone.

iii. Line 85: “recent preprints have found” – should be something like “studies in recent preprints show”

iv. Line 90 “casing” – should be “causing”; also the “and” before “casing” should be removed, as it is not a complete sentence as is

v. Line 100 – perhaps missing word “been”

vi. Line 110 – change “do” to “due”

vii. Lines 110-114 – awkward sentence. Suggest, “Furthermore, the impact of social isolation and loneliness on physical health is on par with that of…”

viii. Line 115-120

1. use of “due to” twice in same sentence

2. “and” is placed before #3 and #4

3. Also, this is a gigantic sentence that needs to be broken into two separate sentences

ix. Line 122-124 – awkward sentence

x. Line 124-125 – should be “This cross-sectional study…”

xi. Line 135 – if number will be used to start a sentence, should be spelled out

xii. Line 141 – should be “IP address”

xiii. Line 141 – when referring to people, it is “who” or “whom” instead of “that”

xiv. Not certain about format used for some citations (e.g., Reddit, ProPublica, CDC, Johns Hopkins).

xv. Line 172-174 – awkward sentence uses “and has been shown to be” twice

xvi. Some sentences start with “This” and do not reference a noun. Example Line 199-200.

xvii. “epidemiological of risk” is used a few times – not clear what is meant, maybe a typo? Examples Line 217, Line 213.

xviii. Line 259-263 – run-on sentence (“which indicates…which indicates…” within same sentence)

xix. Line 303 – “associate” should be “associated”

xx. Line 413 – “…with of COVID-19 concern…” – need to remove “of”

xxi. Line 414 – need to add the word “with” – sentence not complete

4. At times, the manuscript leaves out important details, and in general, would benefit from re-wording to convey information more accurately. Listed are instances of concern as examples, and it would likely be beneficial if the authors would use the same eye to re-examine the manuscript a bit more broadly.

a. Introduction: “Overall, some epidemiological models have predicted that there will be 1.1 – 1.2 million deaths in the United States and 250,000 deaths in Great Britain (Ferguson et al., 2020).” This sentence comes at the end of a paragraph that does a nice job of covering ranges of estimates concerning COVID-19’s R0 and fatality rate. Then suddenly, the authors use an unmitigated estimate of deaths, citing Ferguson et al., which is meant to model mortality in the “… absence of any control measures or spontaneous changes in individual behaviour…”. There are other relevant considerations of the model, including that it does not account “for the potential negative effects of health systems being overwhelmed on mortality.” The authors need to include more of this information to give the reader an accurate sense of its relevance, particularly in light of the moderate way they have approached the other estimates.

b. Line 71: Is use of “Spanish flu” conventional in the field? Perhaps “1918 influenza pandemic” or “1918 H1N1 pandemic” or other wording is more accurate and informative.

c. Line 85: “…increased Google mental health searches…” Consider rewording to say “internet mental health-related keyword searches using the Google search engine,” or similar.

d. The authors use “in modern times” in multiple places. Use of this phrase is probably fine, but more meaning would be gleaned if they gave a little more information, such as “since a [particular year or event].” The example in Line 99, “…leading to the largest decrease in world trade and GDP in modern times.” There are major events last century (WWII, Great Depression, etc.) that are familiar to most readers—is there a semi-recent event that can be accurately pointed to instead as a comparison?

e. “Associated” is used throughout the manuscript, but “positively” or “negatively” correlated or similar would be more informative.

i. Example Line 105

f. Lines 136-141 – sentence is too long and implies that limiting participation to certain countries led to removing participants based on age, etc. Suggest starting a new sentence after “Europe (n = 245)” on Line 139.

g. Related to above, Lines 139-141 concerning how participants were excluded is confusing. The authors simultaneously describe inclusion criteria (“18 or older”) and the number of individuals removed for not meeting those criteria (“n=12”), so that it seems like 12 people were kept in because they were 18 or older. Also consider the following sentence where inclusion criteria are mentioned again. This information can be more streamlined.

h. Mean age and range should include the unit (years)

i. Line 200 – “year income” – probably meant “annual income”

j. Line 354-356 – confusing sentence – suggest, “Our sample demographic was skewed toward higher education and was predominantly Caucasian, consistent with online recruitment studies assessing larger…”

k. The very next sentence starts with “in these models” and it is unclear to the reader whether the authors mean the larger online recruitment studies that they just referred to or their own models in the current paper.

l. Lines 354-356 seem out of place. If Lines 356-358 do refer to the larger studies they should be moved with Lines 354-356; see last comment)

5. General corrections need to be made

i. Some figures have legend-style descriptions (e.g., Figs. 6, 7), while others have very minimal information (only a title?) (e.g., Figs. 2, 3, 4). Some figure legends use “a)” and others “A”, etc.

ii. Figure 7 has “covid_concern” in panel A, which seems like it should be updated to “Covid-19 Concern” similar to panel B.

iii. more stats explanation is needed

1. the authors say they used models and give a link to the statistical code, which will be good for future use, but the reader has little idea how to evaluate these statistical analyses. Throughout the paper, the authors say that a particular variable is “associated” with an outcome, but is their finding similar to a correlation? If so, can they say positively or negatively associated with…? For example, Lines 304-305, “…older age (range 18-77) was associated with COVID-19 concern (B = 0.014, SE = …). More description about the statistical models used would be helpful.

2. what is the “B” value given throughout?

These comments are also uploaded as a separate file for the authors.

Reviewer #2: The study is well designed with a good rationale and good choice of brief symptom measures. The manuscript is exceptionally well written, clear and easy to follow. For the most part, I have only minor suggestions.

Main Issue: The main conceptual issue that I would like to see addressed relates to the interpretation of the findings regarding greater depression symptoms being associated with adherence to more stringent self-quarantine recommendations, despite anxiety symptoms being the strongest correlate of COVID-19 concern. This begs the question as to whether depression is really driving adherence to COVID-19 restrictions per se, or if it’s a spurious correlation related to depressive behavior, not COVID-19 related behavior. Under normal circumstances depression is be associated with social withdrawal. It appears that people in the sample who lost their jobs were also more depressed. Perhaps the reason they are “quarantining” is because they lost their job and have no where to go? To help me understand this better, I wondered specifically how adherence to COVID-19 restrictions was assessed. For example, is this staying home/self-isolating only, or does the “change in behavior” also include COVID-19 specific behaviors such as wearing a mask in public, physical distancing, cleaning hands frequently? If it is only staying home, this may be better explained by depression and job loss and not really specific to COVID-19 which is implied. I tried to find supplemental information specifying the questions used to measure “change in behavior” and “self-quarantine due to COVID-19” however these measures did not appear to be included in the supplemental material attached to the submission, nor were the questions easily located at the provided OSF website. Please clarify in the manuscript how "change in behavior" and "self-quarantine due to COVID-19" was measured.

Related to the above:

Line 307 – loss of employment was associated with both greater COVID-19 concern, greater depressive symptoms and greater anxiety symptoms. If you entered loss of employment into the same model with depressive symptoms and anxiety symptoms, do you get the same results as when you have depression and anxiety symptoms alone? (Line 317-320)

Minor Points

Future directions – consider including measures of personality, in particular the Big 5 Personality traits (NEO-PI). One wonders if personality traits such as conscientiousness or neuroticism might also predict adherence to COVID-19 restrictions?

Line 286 – Figure 7. I don’t think you can use dx = diagnosis when you only had 2 items from the PHQ. It’s an indicator of depressive symptoms that has been shown to be sensitive and specific, but on it’s own would not be sufficient to make a diagnosis.

Line 386 – do you think public education should be specifically geared towards younger population since your results also found that older age was associated with increased COVID-19 concern? (Line 305) ie, younger age associated with lower concern?

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Reviewer #1: Yes: Laura Smith

Reviewer #2: No

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Rapid Assessment of Psychological and Epidemiological Correlates of COVID-19 Concern, Financial Strain, and Health-Related Behavior Change in a Large Online Sample

PONE-D-20-11961R1

Dear Dr. Nelson,

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.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

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,

Vincenzo De Luca

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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

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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

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

Reviewer #1: Yes

Reviewer #2: 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 #2: 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

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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: The reviewer appreciates the authors efforts to correct and improve the submitted manuscript and their important contribution to the literature. Concerns were sufficiently mitigated or resolved via author comments/clarifications and through additions and changes to the manuscript. In particular, improvements are noted in changes to the graphical representations and mitigation of wording regarding interpretations. The reviewer recommends to accept the manuscript as is. Below some additional minor comments may be considered by the authors.

•Fig 6. - consider adding “historical” to the population average scores on the graphs (as it is in the legend)

•Fig 7. – the reviewer doesn’t see “dx” in the figure, as is mentioned in the legend

•Line 401 – typo makes meaning difficult to discern; thing the word “and” may need to be removed

•Line 404-411 – The reviewer suggests mild refinement and tightening of the writing in this section. The sentiments conveyed here should be maintained, but the wording is somewhat confusing and awkward, and generally does not align with the writing capability and tone used in the rest of the manuscript.

Reviewer #2: I am satisfied that my comments based on the first draft of this manuscript have been adequately addressed in the revision of this paper. I could question whether age was included as a predictor in all regressions, as is implied in the discussion but is not clear from the description of the results. It would appear that age was used in a separate regression and not included in the omnibus regression. However, the authors do acknowledge that age is a significant predictor of COVID-19 concern, and aiming interventions at younger populations who may not take precautions as seriously which was my feedback on the original paper. Given the time sensitive nature of this paper, I would not require an additional revision to clarify exactly which regressions age was included in; I would be satisfied to accept the revision as is.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Laura N. Smith

Reviewer #2: No