PONE-D-20-08295

Dietary diversity and physical activity as predictors of abdominal obesity among adults in Dilla town, Ethiopia

PLOS ONE

Dear Mr. Zeleke,

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.

We would appreciate receiving your revised manuscript by Jul 03 2020 11:59PM. When you are 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.

To enhance the reproducibility of your results, we recommend that if applicable you deposit your laboratory protocols in protocols.io, where a protocol can be assigned its own identifier (DOI) such that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

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). This letter should be uploaded as separate file and labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. This file should be uploaded as separate file and labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. This file should be uploaded as separate file and labeled 'Manuscript'.

Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.

We look forward to receiving your revised manuscript.

Kind regards,

Sabine Rohrmann

Academic Editor

PLOS ONE

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

Additional Editor Comments (if provided):

[Note: HTML markup is below. Please do not edit.]

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

**********

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

Reviewer #1: No

Reviewer #2: Yes

**********

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

**********

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

**********

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: Manuscript PONE-D-20-08295: Dietary diversity and physical activity as predictors of abdominal obesity among adults in Dilla town, Ethiopia

It is interesting that the authors assessed obesity in such an area where obesity is often not considered a problem. However, obesity is a global issue today. Appreciating the good efforts made, I have some concerns about the study that are outlined below.

- Throughout the document, it would be good to replace predictors with risk factors, associated factors, influencing factor, etc… Predictors sounds that the authors are developing a prediction model, not performing a regression model.

Line 15- Background/abstract: change “…mortality” to morbidity, obesity doesn’t cause mortality directly

- What was the obesity prevalence by sex, which I think is important to reflect? Obesity is not the same by sex, and this is all known. It would thus be good to present all results stratified by sex.

Lines 30-31: The results of the regression are strange. You reported that the wealth index was positively associated with an increase in obesity, with the OR of 4.75 (>1), which is okay. This is consistent with other studies in developing countries although the association may be the opposite in some other countries, especially in Europe. In the same model, I expected that the protective effect of food diversity and physical activity would be <1 but it is now >1. I got it where it went wrong. For example, you interpreted "physically active is protective with an OR of 2.53" This is not correct. What you have tested in your model is "being inactive", instead of “being active”; that is why you got OR of 2.53 which is >1. The interpretation is wrong as well and also that you would have to reverse the code of "physically active and inactive" and "high food variety and low food variety" in your model. Then you should find <1 OR, where (1-OR) would be the percentage that could be averted due to activity and high food variety.

- Line 80: “…whose ages was”

- Your sample should have been estimated on the basis of the assumption that the prevalence of obesity is different in men and women, rather than with a single proportion assumption–in other words, with two prevalence assumptions. This now seems irreversible. But well, it still seems the size you have already is sufficient to estimate the sample size for men and women separately. This is because you have used a prevalence of 0.5, which is much higher than the actual prevalence leading a larger sample size. If you did it correctly, i.e. taking two prevalence points for men and women, you would get a similar sample size (i.e. with a prevalence of, say 0.25, not just 0.5. I don’t see any stratified results by sex, especially for prevalence. Please do so.

- Lines 151-152: What is the point of performing a logistic regression for each risk factor one by one? It makes no sense, except if you are in a critical situation where the sample size is small given that you have many variables to enter into your model. In fact, it is not recommended that you run this regression for each risk factor one by one. In some cases, a variable may not be significantly associated with an outcome if you fit it in the model alone, but it could be an effect modifier (and its effect could be significant and clinically important) when you fit the variable in your model with other covariates. If you have excluded some variables in that step, please include them in your model and see the results.

- Line 180: “chewed”

- Line 181: accompanied”

- Line 182: Only 2.8% of the women were smokers, while more than a third of the men either smoked during the survey or had smokers before.

- Line 183-84: more than two-third of the participants were physically active

- Have you checked if your covariates were correlated? They seem to be quite a few of them.

Reviewer #2: Thank you for the manuscript. The authors conducted a cross-sectional study in southern Ethiopia, investigating prevalence and determinants of abdominal obesity. They observed a roughly 25% prevalence of obesity; wealth, dietary diversity and physical activity were its determinants. I have some comments and suggest major revision before acceptance.

Abstract:

I would suggest to add “waist circumference” in the methods. The authors mention abdominal obesity but no parameter.

I would expect to read AOR < 1 if the authors write about protectivity (higher dietary diversity and being physically active), however the authors state that “having higher dietary diversity (AOR = 1.89…) and performing physical activity (AOR=2.53…) were found to be protective against abdominal obesity.= I would suggest to rewrite the sentence or invert the AOR.

Introduction

Reference 1 does not seem to be appropriate here (the reference mainly reflects China, but the authors first sentence talks globally). A WHO reference might be more adequate here.

Line 46: Cancer is also one of the major possible consequences of obesity, please do add that to the list of metabolic complications associated with obesity (although cancer is not a metabolic complication but a complex disease, and obesity one of the major risk factors globally speaking).

Line 50: more critical for what? Please detail.

Materials and Methods

Line 89: Would the authors have a reference available for their choice of sampling technique? It seems to be the most appropriate in this setting but a reference would strengthen the authors choice and handling. And how was the one adult from a household chosen, if several adults belonged to a household and were generally eligible? I fear that specific members were chosen (either overweight, underweight or – to be on the safe side – normal weight) – and if this occurred several times, I would question the validity of the current study (and also the 25% prevalence of obesity in the population).

Line 122: What were the 18 selected assets and utilities to calculate the wealth index? This might be a possible supplementary table.

Line 130: I appreciate the tremendous efforts undertaken by the authors/personal to strengthen data and study quality. This was very well done.

Results:

In general, I would suggest to write numbers with two digits, the authors are mixing the number of digits (i.e. OR and AOR with two, 95%CI with three, p-values even more).

Line 168: Wealth Index: As depicted in Table 1, distribution across the three wealth indices was roughly equal. However, the authors write that two thirds were in the middle or above wealth rank – the other view would also be correct, i.e. two thirds were in the middle or below wealth rank. Both are subjective and I would refrain from applying subjective descriptions in the results section.

Table 3: Why not add prevalence and % of obesity into this table?

Line 191: As depicted in Table 4, sex and martial, smoking and chat chewing status never were associated with abdominal obesity, please correct.

Discussion:

The discussion would benefit from a native English reader correcting the grammar.

Thank you for comparing your baseline characteristics to other studies conducted in Ethiopia or further comparable countries.

Line 263: Please add your strengths here, such as your study and data quality protocol. And a limitation might be the cross-sectional design of the study, i.e. causality cannot be investigated. Which adds to further research that is needed.

**********

6. 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

[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 to be viewed.]

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 us at figures@plos.org. Please note that Supporting Information files do not need this step.

Dietary diversity and physical activity as risk factors of abdominal obesity among adults in Dilla town, Ethiopia

PONE-D-20-08295R1

Dear Dr. Zeleke,

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,

Sabine Rohrmann

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

**********

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

**********

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

Reviewer #1: Yes

Reviewer #2: Yes

**********

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

**********

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

**********

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)

**********

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: Henock Yebyo, University of Zurich, Switzerland

Reviewer #2: No