PONE-D-23-02074The Development of Adolescents’ Loneliness during the COVID-19 Pandemic:

The Role of Peer Status and Contacts with FriendsPLOS ONE

Dear Dr. Lorijn,

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Academic Editor

PLOS ONE

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Additional Editor Comments:

As you can see from the reviewers' comments, some changes are suggested, which I agree with. In addition, I stress the importance of reviewing the text with a native English speaker.

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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: 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: No

Reviewer #2: No

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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: I read with great interest the Manuscript titled “The Development of Adolescents’ Loneliness during the COVID-19 Pandemic: The Role of Peer Status and Contacts with Friends” (PONE-D-23-02074), which falls within the aims of PLOS ONE.

In my honest opinion, the study is well written and the topic is interesting enough to attract the readers’ attention. However, the authors should improve the discussion by citing other relevant articles about the topic.

Authors should consider the following recommendations:

- Does this online survey conform to the recommended standards for conducting and reporting web-based surveys, i.e., the Checklist for Reporting Results of Internet E-surveys (CHERRIES)? I suggest specifying this point.

- I recommend further improving the references about the impact of the COVID-19 pandemic on adolescents worldwide by citing some of these recent studies on the topic: DOI: 10.3389/fpsyg.2020.559951; DOI: 10.1016/j.jad.2021.04.016; DOI: 10.1089/cyber.2020.0478.

- It would be interesting to compare the experience of adolescents with that of university students to highlight similarities and differences. In this regard, it may be helpful for authors to read some recently published articles on this topic: DOI: 10.1016/j.psychres.2020.113111; DOI: 10.13129/2282-1619/mjcp-3009; DOI: 10.1038/s41598-022-21288-z.

Reviewer #2: I have read with great interest the manuscript "The Development of Adolescents’ Loneliness during the COVID-19 Pandemic:

The Role of Peer Status and Contacts with Friends" which addresses a very important topic linked to the impact that COVID-19 had on adolescents.

I really enjoyed reading the manuscript, however, I believe that there are several shortcomings. I will list them below in no particular order of importance.

1. Please revise the English. Even if the manuscript is overall easy to follow and understand, there are some areas where the authors could polish the phrasing. For example, at line 6 to 7 "These societal concerns were of special concern during the COVID-19 pandemic" I would encourage the authors to find a synonym for "concern", perhaps. This is just an example, please revise the whole manuscript. Furthermore, I would encourage the authors to revise the introduction section. I would welcome a somewhat more robust argumentation of the importance of this study. Also, it could be helpful if the overall introduction was revised - the arguments provided by the authors seem somewhat fragmented, I would want to see more coherence and flow.

2. If you choose to provide graphics, please make sure that they are easy to read. The ones provided are very blurry and hard to follow. Also, I would replace figure 3 and 4 with tables containing percentages/means. This is somewhat a personal preference, as I find more easy to follow a table than a graph. If the authors choose to retain the graphs, please add the percentages/means to each graph.

3. I would welcome a more robust introduction with a clearer emphasis on the importance of the study. I would also try to be more concise, as at times I had the impression of reading sections of the procedure/measurement.

4. The discussion section conveys the personal interpretation of the authors, however, I would like to see a more theoretically based interpretation of the findings. Furthermore, I would welcome further practical implications of the findings.

5. In the Results - Descriptive statistics section, there are some things I would welcome more details about. For example, the authors mention "Stability in students’ feelings of loneliness was moderate to strong". What does this mean? I see a correlation afterwards and I imagine that it is the correlation for LACA scores from T1 correlated to T2 and T2 with T3 (measures)? Also I am puzzled by the choice of words, stability. It is highly expected that the scores from the same instrument correlate.. Maybe there is a nuance there that the authors could shed some light on.

6. In the Results - Descriptive statistics section, the authors say "Although measured in the same survey, feelings of loneliness differed between March-May ‘20 and Oct/Nov ‘20", and then provide a correlation score. In the light of the previous understanding of the statistics linked to the stability, I have to admit that this is confusing. Furthermore, when differences are mentioned, I usually expect a T test, not necessarily a correlation. Could the authors indicate the reasoning/rephrase this section?

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Reviewer #1: No

Reviewer #2: No

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The Development of Adolescents’ Loneliness during the COVID-19 Pandemic:

The Role of Peer Status and Contact with Friends

PONE-D-23-02074R1

Dear Dr. Lorijn,

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,

Giulia Ballarotto

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: (No Response)

Reviewer #2: Yes

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

Reviewer #1: (No Response)

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: (No Response)

Reviewer #2: No

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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: (No Response)

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: (No Response)

Reviewer #2: (No Response)

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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: No

Reviewer #2: No

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