PONE-D-20-05561

The effect of mobile text message on behavioral risk factors of cancer among college students, northeast Ethiopia: a randomized controlled trial protocol

PLOS ONE

Dear Dr. Hussien,

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 provide thorough responses to the reviewers' comments, particularly to the questions posed by Reviewer 1 and Reviewer 3.

Please submit your revised manuscript by Sep 11 2020 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'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• 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: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Nancy Beam, PhD

Staff Editor

PLOS ONE

Journal Requirements:

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. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Partly

Reviewer #2: Yes

Reviewer #3: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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

**********

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 #3: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: This is a "Registered Report Protocol", where the investigative team plans to conduct a 2-arm randomized controlled trial (RCT) to test the effectiveness of mobile text messages in providing necessary health information for cancer prevention, compared to controls. While the study design is appropriate, I have some serious concerns on the actual science behind the study. In particular, I am not sure what an over-simplified RCT of this sort (spanning across only 6 months) will actually do, if any, to the cause. The intervention will be delivered, strictly, via text messages, to non-cancer (or, no prior diagnosis of cancer) subjects. There is no way to ascertain even whether the subjects are "actually reading/attending" the text messages, and responding to those (given that none of the subjects enrolled are actually cancer patients). Furthermore, following those for 6-months seemed to be a very short time to evaluate any effectiveness in that regard. In my opinion, all these will entail a "very pilot" study.

I do have some additional comments that require attention.

1. Sample size/Power: The sample size/power statement should explicitly mention the statistical test used.

2. Randomization: From the randomization procedure described, it is not clear if this is a simple randomization, or a block. I would recommend a block strategy, which will ensure sample size are balanced across groups over time.

3. Randomization: The authors need to mention how "Allocation Concealment", and "Blinding", considered two separate concepts, will be actually performed. Refer to this article below:

https://www.bmj.com/content/347/bmj.f5518

4. Statistical Analysis plan: The design is longitudinal; so I was wondering why a small longitudinal analysis plan was not proposed. A longitudinal analysis (via mixed models, or generalized estimation equations) will allow one to have a better picture on how the trial actual progressed, and the subsequent estimates of the relevant parameters.

Reviewer #2: Dear Author,

First of all, I appreciate that this is a great effort and I wish successful completion in the implementation of this clinical trial!

Follows, some general comments, and afterwards I suggest some corrections in some small syntax or logical errors:

• The bibliographic reporting system is incomplete. There is no reference within the text to the cited bibliography at the end.

• in page 1: Department of epidemiology and biostatics … it’ ok… but it would be better to use the word "biostatistics". This term is derived from the Greek term “βιοστατιστική” which is pronounced “biostatistiki”.

• in page 8: Epidata version 3.1: There is no relevant link. Moreover, it would be helpful to have a brief explanation, as a footnote, about using this software.

Also, please correct:

• in page 1: “Department of public health nutrition, ,…” with: “Department of public health nutrition, ….”

• in page 4: “..which could be helpful to raise cancer awareness…” with: “..which could be helpful to raise awareness among citizens regarding cancer issues..”

best regards

good luck

Reviewer #3: The goal of the proposed study is to evaluate the effectiveness of mobile text message in improving behavioral risks of cancer among college students in Ethiopia. The proposed study addresses an important topic and has the potential to be an effective intervention aimed at improving cancer risk knowledge and perception.

The authors plan to send a text message once a day for two months, which seems feasible. The daily messaging strategy should be effective given the relevant literature, but have the researchers done any kind of pilot testing to determine the appropriate amount of text messages for college students? They might become fatigued after receiving a message everyday for two months and tune out the messages, especially since those in the treatment group are receiving messages about one topic (cancer risk).

Why are the participants in the control group only receiving one message per week and not one a day? Can the researchers also explain their rationale for measuring cancer risk knowledge and risk perception at baseline and six months post-randomization? Why not immediately after the two months?

On page three, the authors state, “ Behavioral risk factors include tobacco use, harmful use of alcohol, unhealthy diet and physical inactivity [4]. These lifestyle factors are potentially avoidable if appropriate preventive interventions are implemented.” I don’t disagree with this claim, but the authors should also consider the structural factors and a lack of access to resources in some cases that can prevent one from making lifestyle changes.

The health belief model is mentioned at various points throughout the manuscript, but there is no background information presented in the literature review. There should also be a stronger rationale for why this framework was chosen for the current study.

There needs to be more information provided in the “recruitment and randomization” section. Based on the information here, it is difficult to determine if this study is feasible. Have the administrators from the universities already agreed to these protocols? Are there contracts in place with a service provider or third party who will be sending the messages? Who will write the messages? How will students opt in to the program? What is the procedure for opting out? How will students provide consent over text messaging?

There also needs to be additional details provided about the messages. Are the researchers writing the messages? Are staff and faculty from the universities writing them? Will there be student/peer input so the language resonates with the college students? Will a messaging expert review these before they are sent out? It would also be helpful to see examples of the messages the researchers plan to use.

“Primary outcomes” section, page seven- please cite the scales you plan to use to measure the health belief model variables.

Will the surveys be sent over the phones?

The NIAAA measure for alcohol intake will be used to “assess participants’ consumption in the past 1 month.” However, this does not seem to align with the original timeline for collecting participant data.

On page eight, the authors make it sound as though the questionnaires will be administered in person. Is this the case? If so, how will responses be matched (baseline and post-test) and how will the researchers match responses with phone numbers/text message (control or treatment) group? There needs to be more details about how responses to the questionnaire items (pre and post) will be matched with participants in the text messaging groups. Also, can the authors explain why they are administering the questionnaires in person rather than through a survey link sent in a text message?

I would also like to see more information about the message content. The researchers mention on page nine that the messages will be “positively-framed” and “semi-personalized.” Can the researchers provide examples of these? Is there a communication specialist on this project who is writing and/or reviewing the messages in accordance with communication theory?

**********

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

Reviewer #3: 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.]

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.

PONE-D-20-05561R1

The effect of mobile text message on behavioral risk factors of cancer among college students, Northeast Ethiopia: a randomized controlled trial protocol

PLOS ONE

Dear Dr. Hussien,

Thank you for submitting your manuscript to PLOS ONE and for responding to the previous round of reviewers' comments. There remain a number of points which have not been fully addressed, as explained in reviewer 3's comments appended below.

Therefore, we invite you to submit a revised version of the manuscript that addresses these additional points raised during the review process.

I would also suggest that you change 'text message' to 'text messages' in your title, as that is more grammatical.

Please submit your revised manuscript by Jan 09 2021 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'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• 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: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Dr Joseph Donlan

Staff Editor

PLOS ONE

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

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #1: Yes

Reviewer #3: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #1: Yes

Reviewer #3: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Reviewer #1: Yes

Reviewer #3: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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

**********

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

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors addressed my previous comments to a greater degree of satisfaction. I have no further comments.

Reviewer #3: Thank you to the authors for taking the time to provide thoughtful responses to my comments.

The authors did not fully respond to my first question. Did they complete a pilot study or collect some kind of preliminary data to determine the amount of messages to send? For this same point, can the authors explain what they mean by framing messages so they are "attractive"?

The authors did not do a sufficient job of elaborating on the HBM in the literature review. There is no explanation of the major constructs including barriers, benefits, efficacy, cues to action.

The inclusion criteria states that participants must be between 15-35. Can the authors provide a rationale for this large age gap? This is a wide range and the health behaviors of adults in their 20s/30s are likely to be different from individuals in their teens.

The authors did include a sample message, but I would like to see more examples of the content that will be used in this study. Given that this is a messaging study, there needs to be more explanation of the actual messages and what they look like.

**********

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 #3: 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.]

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.

PONE-D-20-05561R2

The effect of mobile text messages on behavioral risk factors of cancer among college students, Northeast Ethiopia: a randomized controlled trial protocol

PLOS ONE

Dear Dr. Hussien,

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 respond to the comments from Reviewer 3. Specifically, please copyedit the manuscript paying special attention to the messages being tested. Please carefully consider the reviewer's advice on the message content.

Please submit your revised manuscript by Mar 15 2021 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'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• 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: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Nancy Beam, PhD

Staff Editor

PLOS ONE

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

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #3: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #3: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Reviewer #3: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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

**********

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

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: I think this manuscript pending two criteria are met:

The authors proofread the added content about the HBM within lines 75-83 since there are a few grammatical errors. For example, "believe" should be "belief." The authors should also include at least one or two lines mentioning self-efficacy and cues to action given that these are variables within the HBM, but are not mentioned here.

The authors should carefully proofread the messages that they plan to use, which are listed within lines 175-188. This is critical given that this is a messaging study. Additionally, although this is perhaps beyond the scope of this study, I recommend that the authors be careful about using messages like, "cancer is fatal had no certain cure" since this fear-based and might lead to the recipient tuning out the message completely. Also, the message, "although you are addicted to drink alcohol, you can decrease the amount and quit it through time” is not entirely accurate (and also needs to be proofread) since people who are addicted to alcohol cannot always decrease their consumption and/or quit over time. Finally, messages like, "avoid laziness!" might be seen as condescending and can produce a boomerang effect. Some of these messages also fail to consider structural/social determinants of health and put all of the emphasis on individual behavior change. Again, I'm not sure if all of this can be addressed here, but these are points that should be kept in mind while moving forward with this project.

The authors have addressed my other concerns and I do not need to review another version of this (although I am happy to do so if the editor prefers) because I trust that the authors will make these changes.

**********

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 #3: 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.]

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.

PONE-D-20-05561R3

The effect of mobile text messages on behavioral risk factors of cancer among college students, Northeast Ethiopia: a randomized controlled trial protocol

PLOS ONE

Dear Dr. Hussien,

Thank you for submitting your manuscript to PLOS ONE. Apologies for the delay in returning this to you. The orignial editor was unavailable so this paper was passed on to myself for review, and we struggled to identify reviewsers. 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.

This is a minor but important revision: given reviewer comments, it is imperative to highlight likely problems and biases as identified by reviewer comments more clearly in your disucssion (and/or justifiy better the reasons for the chosen study design, intervention development and operationalisation in the methods). This should also help the framing of the write-up of your completed study.

Please submit your revised manuscript by May 08 2021 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'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• 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: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Lion Shahab, MA MSc MSc PhD CPsychol

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.

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

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #3: Yes

Reviewer #4: Yes

Reviewer #5: Yes

**********

2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #3: Yes

Reviewer #4: Partly

Reviewer #5: Yes

**********

3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Reviewer #3: Yes

Reviewer #4: No

Reviewer #5: Yes

**********

4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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

Reviewer #5: No

**********

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

Reviewer #5: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

You may also provide optional suggestions and comments to authors that they might find helpful in planning their study.

(Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #3: I appreciate the authors' efforts to revise the manuscript and for their attention to my comments. I "accept" the manuscript in its current form and the authors have addressed my previous concerns. However, I want to reiterate the importance of having the messages reviewed by communication/messaging experts who have experience with text-messaging studies aimed at health behavior change, so that they can offer suggestions for framing, wording, etc. This study has the potential to make a unique and important contribution to the text-messaging/mobile health literature. I look forward to reading the findings once this is implemented and the data is analyzed.

Reviewer #4: Thank you for the opportunity to review this protocol, which outlines the study procedures and analysis plan for an RCT of a text message intervention informed by the Health Belief Model to increase the awareness of behavioural risk factors for cancer in college students in Ethiopia. The protocol has several strengths, including the development of the intervention on the basis of health psychology theory and a sound statistical analysis plan. However, I have highlighted some concerns below for the authors’ consideration.

Major comments

1. As students in the same college are individually randomised to the intervention and control arms, there’s a large risk of contamination (e.g. students may simply compare the text messages received). Due to the target population and setting of interest, this study would have benefitted from the use of a cluster RCT design. However, as recruitment has already been completed, this should at the very least be discussed as an important limitation of the study design. Linked to this, as recruitment is already completed, I don’t see how this can usefully be published as a Registered Report Protocol, as there’s insufficient scope to improve on the study design.

2. When setting up the rationale for the study in the Introduction, a better lay of the land is needed. It would be useful to know the proportion of adults and/or students in Ethiopia with access to mobile phones. There’s a vast literature on the effectiveness of text messages for smoking cessation, physical activity, etc. (please see a suggested reference to a review of systematic reviews below). It would be important to refer to this wide literature in the Introduction, that positive effects on behaviour have been observed, and then state that few existing interventions have been evaluated in LMICs, including Ethiopia (off the top of my head, I’m only aware of a couple for smoking cessation, with one in China and one in Vietnam):

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4406229/

https://pubmed.ncbi.nlm.nih.gov/26730560/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7381024/

3. Although it’s a compelling aspect of the study that the intervention has been developed on the basis of the Health Belief Model, it’s unclear how the intervention messages map onto the different components of the HBM. It would be useful to make this more explicit, for example by including a table with example messages and indications in a second column as to how each message maps onto the different components of the model. At present, it’s unclear whether all components were covered by the messages. This is important to understand, as we wouldn’t expect the intervention to have an effect on, for example, self-efficacy, if the intervention messages themselves don’t directly attempt to boost self-efficacy.

4. It’s unclear why participants aren’t recruited on the basis of engaging in one or multiple unhealthy behaviours? There’s arguably no need to raise awareness that excessive alcohol consumption is a risk factor for cancer in those who don’t engage in heavy drinking. It’s also unclear why the primary outcome isn’t behaviour change – this would be of greater interest to the public health community and a more typical outcome for an RCT.

Specific comments

Introduction

5. The second sentence about cancer incidence and mortality refers to global cancer statistics but the citation refers to cancer rates in Ethiopia. Please change to a more suitable reference, e.g. https://acsjournals.onlinelibrary.wiley.com/doi/full/10.3322/caac.21660

6. It would be useful to more explicitly state that although there are many different risk factors for cancer (e.g. behavioural, biological, environmental), not all of these are modifiable, and that this study focuses specifically on modifiable health behaviours. Environmental exposure to, for example, air pollutants, and soil and drinking water contaminants, could theoretically also be addressed via behaviour change (although may require wider policy changes to impact behaviour).

7. Line 74 – there are some typos here, e.g. “The” is missing at the beginning of the sentence; “health related” rather than “healthy related”.

8. Line 85 – “and by their confidence that the recommended action” – this is repeating information on line 79; please remove.

9. Line 86 – “Thus, we will use the HBM to measure the perception…” – this doesn’t fully elaborate on the study aims, which also includes the examination of behaviour change. Given this is described in the next paragraph, I’d suggest changing this to a broad statement that the HBM will therefore be used to develop an intervention to increase awareness of and perceived susceptibility to cancer, and affect change to four key health behaviours.

10. Rather than stating both hypotheses and objectives for the study, I’d suggest including a list of the key research questions and how they relate to the different follow-up assessments and outcome variables of interest. For example, the first research question may be whether participants allocated to the intervention arm, compared with those allocated to the control arm, have increased knowledge of the cancer risks of smoking/alcohol/etc at a 6-month follow-up. Please list all of the main research questions and end points.

Methods

11. Although a CONSORT flow chart is included, it would be useful to reference the CONSORT checklist in the ‘Study design’ section and mention that this was used in the design and reporting of the study: http://www.consort-statement.org/

12. The study setting section describes the number of staff members but the eligibility criteria state that only students are eligible to take part – it’s unclear why staff members aren’t also eligible? Also, it’s unclear why only those aged 18-35 years are eligible to take part? Please provide a rationale and remove any superfluous information about the employees in the ‘Study setting’ section (as they aren’t part of the target population).

13. The authors state that the study is powered to detect a difference in “knowledge and perception of cancer risk” but then go on to state that the power calculation is based on perceived self-efficacy – these are not identical psychological constructs, so it would be important to clarify which of these is the primary outcome for the study. It would also be useful to contextualise the 2.9-point expected difference in knowledge or self-efficacy – is this on a 5-point or 7-point Likert scale?

14. It’s unclear what this means “Sample size will be allocated to…” – does this mean only two colleges will be used for recruitment? If so, this needs to match the above ‘Study setting’ section.

15. “Students’ IDs will be obtained…” – do you mean that all students with an ID will be contacted and asked if they are willing to join the trial?

16. “Then; simple random sampling method will be used to select eligible study subjects” – this sounds incorrect. Surely interested students will be assessed for eligibility via a screening survey, with eligible participants randomised with simple randomisation to the intervention or control arm?

17. Blinding – it should also be stated that the researchers will be blinded to the allocation sequence (i.e. single blind).

18. Control – please provide a bit more information on what is considered a ‘general health message’ in this context. I assume these won’t mention the four health behaviours of interest?

19. Primary outcomes – please comment on whether the 5-point Likert scale has been validated.

20. Secondary outcomes – please provide references to the specific food frequency questionnaire that will be used and whether it has been validated, the IPAQ-S and whether it has been validated, the NIAAA tool to assess alcohol consumption and the WHO tool to assess smoking. I’d recommend using the AUDIT or AUDIT-C for alcohol: https://apps.who.int/iris/handle/10665/67205 It’s unclear whether the smoking assessment will examine cigarette smoking only or any kind of tobacco?

21. The proposed statistical analysis plan looks good.

Reviewer #5: Dear PLOS ONE Editors,

Thank you for the opportunity to review an article entitled “The effect of mobile text messages on behavioral risk factors of cancer among college students, Northeast Ethiopia: a randomized controlled trial protocol” prepared by Hussien and colleagues.

This manuscript has already undergone peer review. It is well written and provides the relevant information for a trial protocol. However, I have a number of suggestions for the authors to consider for how to improve the proposed intervention and the trial, if still possible.

[1] The authors selected Health Belief Model (HBM) as a theoretical basis for the intervention. The constructs specified by HBM can contribute to risky behaviours and behaviour change (e.g. beliefs about what are risk factors), but they primarily focus motivational factors. However, there are other important determinant of behaviour change – as mentioned by other reviewers earlier (e.g. social determinants). For example, another model of behaviour – Capability, Opportunity, and Motivation (COM-B) shows that for any behaviour change to take place one not only needs motivation, but also capability (knowledge, skills) as well as opportunity (social and physical). Therefore, an intervention that only target some of the COM-B elements without addressing other known barriers is likely not to be sufficiently effective. The evaluation survey is accounting for it (e.g. by asking about income sufficient to change behaviour), but it does not seem that the intervention suggest ways of changing behaviour when one has insufficient income. Can the authors still consider and address the limitations of HBM and if the intervention content could still be improved?

[2] I see some further potentially missed opportunities for increasing the effectiveness of the intervention. For example, important and effective components (or behaviour change techniques) of behaviour change interventions are setting goals, monitoring and feedback. Without specifying goals for behaviour change early on for the participants it will be quite improbable that they will engage with the intervention and attempt behaviour change (the attempts being a first step to change the behaviour).

[3] The intervention targets are very broad (and address a number of health behaviours) – ideally the content of the interventions would be tailored to the risk behaviours of that individuals to increase the relevance of the intervention. Previous SMS texting interventions that target a single behaviour (e.g. smoking cessation) were very complex and detailed, and it is unlikely that only a few sms text about one behaviour will be sufficient to change that behaviour.

[4] Students in public colleges are more educated and technology-savvy group in the population. Additionally, they may also be at lower risk of engaging in some of the risky behaviours, and given their young age their cancer risk is also much lower. It would be important for the authors to clarify the benefit of testing this intervention among this population, rather than among adults in the general population for whom it may be more relevant and who may benefit more from it.

[5] Additionally, the eligibility criteria do not specify that the participants should engage in any unhealthy behaviour. It is therefore possible that all of the participants will lead a healthy lifestyle and have no unhealthy behaviours. This is another important limitation of the study that will make it more difficult to show any effect of the proposed intervention. Can the authors consider to first screen participants for unhealthy behaviours and recruit only those who exhibit behaviours and the levels of these behaviours (e.g. smoking, high alcohol consumption, etc) that can realistically show any reduction or improvement during the trial?

[6] Texting has been shown to be a cost-effective medium to deliver education or more complex behaviour change interventions for a number of health risk behaviours. Texting as a technology can have more reach than newer technologies (e.g. smartphones app) as they can be delivered on any mobile device. However, sms texts can be ignored, the options for content are very limited, and there is little or no possibility to assess engagement with the texts objectively. I encourage the authors to include more discussion around the pros and cons of using texting, and how some of the limitations for the interventions and evaluation will be addressed.

If the authors are no longer able to change the intervention or the study design, then it would be very helpful for the published trial protocol to include a discussion of these important limitations and highlight the contribution that this study still brings despite the known limitations.

With best wishes,

Dr Aleksandra Herbec

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Reviewer #3: No

Reviewer #4: No

Reviewer #5: Yes: Dr Aleksandra Herbec

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PONE-D-20-05561R4

The effect of mobile text messages on knowledge and perception towards cancer and behavioral risks among college students, Northeast Ethiopia: a randomized controlled trial protocol

PLOS ONE

Dear Dr. Hussien,

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.

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We look forward to receiving your revised manuscript.

Kind regards,

Lion Shahab, MA MSc MSc PhD CPsychol

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Does the manuscript provide a valid rationale for the proposed study, with clearly identified and justified research questions?

The research question outlined is expected to address a valid academic problem or topic and contribute to the base of knowledge in the field.

Reviewer #4: Yes

Reviewer #5: Yes

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2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses?

The manuscript should describe the methods in sufficient detail to prevent undisclosed flexibility in the experimental procedure or analysis pipeline, including sufficient outcome-neutral conditions (e.g. necessary controls, absence of floor or ceiling effects) to test the proposed hypotheses and a statistical power analysis where applicable. As there may be aspects of the methodology and analysis which can only be refined once the work is undertaken, authors should outline potential assumptions and explicitly describe what aspects of the proposed analyses, if any, are exploratory.

Reviewer #4: Yes

Reviewer #5: Yes

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3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable?

Reviewer #4: Yes

Reviewer #5: No

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4. Have the authors described where all data underlying the findings will be made available when the study is complete?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception, at the time of publication. 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 #4: Yes

Reviewer #5: No

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Reviewer #4: Yes

Reviewer #5: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above and, if applicable, provide comments about issues authors must address before this protocol can be accepted for publication. You may also include additional comments for the author, including concerns about research or publication ethics.

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Reviewer #4: The authors have done a fine job addressing the reviewer comments. I only have two remaining points. In the abstract, "To test the change in score of HBM" is unclear and should be changed to "To test the change in knowledge and perception" or similar. The 'Trial status' section still says that "We are currently recruiting and enrolling students in the study. As of February 2020, we have enrolled 160 participants." Given the authors' response that the intervention is yet to be developed and delivered, please amend this accordingly.

Reviewer #5: I would like to thank the Authors for responding in detail to my suggestions and questions. It is very helpful to see it clarified that the primary outcome are changes in knowledge/perceptions, rather than behaviours. I accept most of the arguments put forward by the Authors and understand the urgency to conduct this research as per the original protocol and within the limits posed by the resources available. I believe that the manuscript would be strengthened if the Authors incorporated some of the arguments from their latest response into the methods and the discussion section of the manuscript, i.e. to offer an additional justification (and a discussion of the limitations) for the different decisions made regarding study design.

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Reviewer #4: No

Reviewer #5: No

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The effect of mobile text messages on knowledge and perception towards cancer and behavioral risks among college students, Northeast Ethiopia: a randomized controlled trial protocol

PONE-D-20-05561R5

Dear Dr. Hussien,

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,

Lion Shahab, MA MSc MSc PhD CPsychol

Academic Editor

PLOS ONE

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