Effectiveness of dyadic interventions in improving outcomes for adults with multiple long-term conditions and/or frailty and their informal carers: A systematic review protocol

Stella Arakelyan; Michaela Gilarova; Mozhu Ding; Atul Jaiswal; Atul Anand; Karin Modig; Maria Kristiansen; Daniela Lillekroken; Susan D. Shenkin; Jill Manthorpe; Bruce Guthrie

doi:10.1371/journal.pone.0333728

Peer Review History

Original SubmissionSeptember 22, 2025
22 Dec 2025 Decision Letter - Robbert Huijsman, Editor Dear Dr. Arakelyan, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Feb 05 2026 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. A letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. 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Please note that we cannot proceed with consideration of your article until this information has been declared. Please include your amended Competing Interests Statement within your cover letter. We will change the online submission form on your behalf. 4. Please provide a complete Data Availability Statement in the submission form, ensuring you include all necessary access information or a reason for why you are unable to make your data freely accessible. If your research concerns only data provided within your submission, please write "All data are in the manuscript and/or supporting information files" as your Data Availability Statement. If the reviewer comments include a recommendation to cite specific previously published works, please review and evaluate these publications to determine whether they are relevant and should be cited. There is no requirement to cite these works unless the editor has indicated otherwise. 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 If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references.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. Additional Editor Comments: Thank you for tou clear protocol paper. The reviewers give you some minor points for revision. [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? Reviewer #1: Partly ******** 2. Is the protocol technically sound and planned in a manner that will lead to a meaningful outcome and allow testing the stated hypotheses??> Reviewer #1: Yes ****** 3. Is the methodology feasible and described in sufficient detail to allow the work to be replicable??> Reviewer #1: 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 Reviewer #1: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English??> Reviewer #1: Yes ****** 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. Reviewer #1: Dear Dr. Arakelyan, Thank you for your manuscript and the interesting topic presented. This manuscript addresses an important research area and presents a well-structured protocol. I have a few concerns regarding the methodology and focus of this protocol. 1) Methods: In the text, you claim to include articles from 2010 onward. However, in Table 1. Study selection criteria, the search inclusion is from 2016. Please clarify the inclusion criteria and remain consistent. 2) Please provide clearer examples of comparators. 3) The two-pronged aim is focusing on a) co-resident older informal caregiver and b) informal caregiver (friends, family). The value of the delineation is unclear in the manuscript and should be further elaborated. 4) The protocol has not clarified how a review of intervention effectiveness can inform the re-design, tailoring, and implementation of health services. There is a gap between effectiveness research and implementation research that the author should clearly address. ****** 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 ******** [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 ensure your figures meet our technical requirements, please review our figure guidelines: https://journals.plos.org/plosone/s/figures You may also use PLOS’s free figure tool, NAAS, to help you prepare publication quality figures: https://journals.plos.org/plosone/s/figures#loc-tools-for-figure-preparation. NAAS will assess whether your figures meet our technical requirements by comparing each figure against our figure specifications. Attachments Attachment Submitted filename: PONE-D-25-50837_review feedback.docx https://doi.org/10.1371/journal.pone.0333728.r001
Revision 1
5 Jan 2026 Author Response We appreciate the helpful and constructive comments provided by editorial team and Reviewer 1 which we have addressed in full. Comment 1: Methods: In the text, you claim to include articles from 2010 onward. However, in Table 1. Study selection criteria, the search inclusion is from 2016. Please clarify the inclusion criteria and remain consistent. Response 1: Thank you for highlighting this. We confirm that articles published from 2010 onward were eligible for inclusion. Table 1 has been corrected to reflect this. Comment 2: Please provide clearer examples of comparators. Response 2: We consider for inclusion any comparator used in the original studies, including standard or usual care and modified usual care if additional components are clearly stated and described. We have revised the manuscript to clarify and added examples (please see the revised text below). We will consider studies reporting on any type of comparator intervention, including standard or usual care in the setting the intervention was implemented. Studies in which the comparator intervention involves minor enhancements to standard care, such as distribution of informational materials or training of carers or dyads, will also be eligible for inclusion if additional components are clearly stated and described. Comment 3: The two-pronged aim is focusing on a) co-resident older informal caregiver and b) informal caregiver (friends, family). The value of the delineation is unclear in the manuscript and should be further elaborated. Response 3: We described in the introduction (lines 82-83) that informal carers often experience negative effects of caregiving, and these effects are more prominent in older spouse or partner carer who commonly provide more intensive support and live with own long-term conditions and have many unmet support needs. In contrast, adult family members, relatives, or friends may or may not be co-resident and typically provide care of lower intensity and shorter duration. Distinguishing these groups provides a more nuanced understanding of caregiving contexts, needs, and intervention effects. We have revised introduction to better articulate this delineation (please see the revised text below). It is also unclear if the effects of dyadic interventions differ according to informal carer characteristics, such as between co-resident older carers (spouses or partners), who typically provide higher-intensity care while managing their own long-term conditions [10] and adult family members, relatives or friends, who may or may not be co-resident and often provide lower intensity support. Comment 4: The protocol has not clarified how a review of intervention effectiveness can inform the re-design, tailoring, and implementation of health services. There is a gap between effectiveness research and implementation research that the author should clearly address. Response 4: We agree that the gap between evidence and practice remains a challenge, and progress in addressing it has been slow. Contributing factors include unclear communication of research findings to service providers and policymakers, as well as limited financial and political support. While researchers alone cannot resolve funding constraints or ensure political commitment, we will work collaboratively with stakeholders to co-produce an “effective action policy brief” that translates evidence into practical, actionable guidance. This guidance will support the co-development and implementation of dyadic interventions that are effective, acceptable, feasible, and tailored to local contexts. The final paragraph of the discussion has been revised to reflect this (please see below). For service providers and policymakers, the review will provide evidence-based insights into the types of community-based dyadic interventions that have the potential to reduce unmet support needs and enhance care experiences and outcomes for people with MLTC and/or frailty and their carers. To help bridge the gap between research and practice, the review findings will be disseminated not only through academic publications but also, in collaboration with key stakeholders, co-produced as an “effective action policy brief” that translates evidence into practical, actionable guidance. This guidance can inform the co-development and implementation of dyadic interventions that are effective, acceptable, feasible, and tailored to local needs and contexts. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0333728.r002
15 Jan 2026 Decision Letter - Robbert Huijsman, Editor Effectiveness of dyadic interventions in improving outcomes for adults with multiple long-term conditions and/or frailty and their informal carers: A systematic review protocol PONE-D-25-50837R1 Dear Dr. Arakelyan, 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 will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact billing support . 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, Robbert Huijsman, PhD Academic Editor PLOS One Additional Editor Comments (optional): Thanks to the authors for their revision and carefull responses to the reviewers. There are no further comments, the revision is satisfactory. Reviewers' comments: https://doi.org/10.1371/journal.pone.0333728.r003
Formally Accepted
Acceptance Letter - Robbert Huijsman, Editor PONE-D-25-50837R1 PLOS One Dear Dr. Arakelyan, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS One. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset You will receive further instructions from the production team, including instructions on how to review your proof when it is ready. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few days to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. 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. You will receive an invoice from PLOS for your publication fee after your manuscript has reached the completed accept phase. If you receive an email requesting payment before acceptance or for any other service, this may be a phishing scheme. Learn how to identify phishing emails and protect your accounts at https://explore.plos.org/phishing. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Professor Robbert Huijsman Academic Editor PLOS One https://doi.org/10.1371/journal.pone.0333728.r004

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