Co-Development and Content Validity of an Instrument to Collect Integratively the Social Determinants of Health in Postpartum Lactating People

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1.   What is the main question addressed by the research?

The development and content validation of an instrument to comprehensively assess social determinants of health (SDH) in postpartum lactating individuals.

The study specifically aims to fill the gap of a lack of validated tools to comprehensively assess these factors in this particular population.

 

2. What parts do you consider original or relevant to the field? What specific gap in the field does the paper address?

The paper's originality and relevance lie in its co-development of the first instrument specifically validated for assessing SDH in postpartum lactating individuals.

This is particularly relevant given that postpartum women are a vulnerable group facing elevated risks related to various SDH factors, and existing healthcare systems often overlook their specific needs or rely on male physiological models. The specific gap the paper addresses is the absence of a validated and comprehensive tool to integratively evaluate SDH in this population.

 

3. What does it add to the subject area compared with other published material?

This study adds a crucial, content-valid, and integratively designed instrument for remote self-administration to the subject area. Unlike other published material that might address individual SDH factors or general populations, this paper provides a tool specifically tailored to the unique circumstances and vulnerabilities of postpartum lactating individuals. It integrates a wide range of factors (demographics, education, employment, home environment, lifestyle, social support, healthcare access, stress, intimate partner violence, insomnia, and nutrition) , some adapted from previously validated questionnaires and others newly developed by the authors, into a single, comprehensive instrument.

 

4. What specific improvements should the authors consider regarding the methodology?

Certain points could be considered for improvement:

• Clarity on Participant Recruitment (Phase 3): Although intentional recruitment was conducted through online media and health centers, further detail on the specific online platforms or health centers used could enhance replicability.
• Discussion of Potential Bias in Expert Panel Composition: The expert panel represented diverse fields. A brief discussion on how potential biases related to the specific disciplinary backgrounds might have influenced the consensus rounds would be beneficial, even if mitigated by the e-Delphi method.
• Longitudinal Validation: While content validity is established, the paper acknowledges that the instrument is at Technology Readiness Level 2 (experimental research on functionality). The authors could explicitly suggest future research on longitudinal validation and reliability testing to ensure the instrument's stability and predictive power over time.

 

5. Are the conclusions consistent with the evidence and arguments presented?

Were all the main questions posed addressed? By which specific experiments?

The conclusions are consistent with the evidence and arguments presented.

The study successfully co-developed and established the content validity of the instrument as aimed.

 

All the main questions posed were addressed through specific experiments:

 

• Co-development of the instrument: This was achieved through a three-phase methodology:

Phase 1 (Pre-design): Involved an extensive state-of-the-art literature review to identify initial items and dimensions

Phase 2 (e-Delphi method): An interdisciplinary expert panel assessed and refined the instrument for sufficiency, clarity, coherence, and relevance through consensus-building rounds, employing statistical analyses such as I-CVI, S-CVI/Ave, AABE, Fleiss' kappa, and Aiken's V coefficient

Phase 3 (Cognitive Interviews): Conducted with postpartum individuals to assess the interpretability and clarity of the instrument, leading to final adjustments.

Establishment of Content Validity: This was directly addressed by the statistical analyses performed in Phase 2, which showed strong agreement among experts (e.g., S-CVI/Ave > 0.95, AABE > 14.26, and kappa and V coefficients > 0.90). The refinements from cognitive interviews further optimized the instrument for clarity and relevance.

 

6. Are the references appropriate?

The references appear to be appropriate and relevant to the study's scope.

 

7. Any additional comments on the tables and figures and the quality of the data.

The quality of the data presented in the results section, particularly the content validity indices, appears to be high, rigorously calculated, and consistently supports the study's conclusions. The detailed descriptions of item modifications based on expert and participant feedback further underscore the thoroughness of the validation process.

Comments on the Quality of English Language

It is an interesting research. I would recommend acceptance after english editing. 

Author Response

We sincerely appreciate the reviewer’s thoughtful comments and constructive suggestions. Reviewer 1 highlights the originality, relevance to the field, consistent conclusions, and overall quality, pointing out the specific gap addressed by the article through an appropriate mixed methodology. Nonetheless, this reviewer suggested methodological improvements, as follows:

• Clarity on Participant Recruitment (Phase 3): Although intentional recruitment was conducted through online media and health centers, further detail on the specific online platforms or health centers used could enhance replicability.

Response: In Phase 3, we have identified the specific online platforms and health center used for recruitment, and these are now described in the revised manuscript to ensure clarity and replicability.

• Discussion of Potential Bias in Expert Panel Composition: The expert panel represented diverse fields. A brief discussion on how potential biases related to the specific disciplinary backgrounds might have influenced the consensus rounds would be beneficial, even if mitigated by the e-Delphi method.

Response: We have expanded the Discussion section to address potential biases arising from the disciplinary composition of the expert panel. Specifically, we discuss how differences in disciplinary perspectives may have influenced the consensus process, and how the e-Delphi method helped to mitigate these effects. Relevant references have been added to support this discussion.

• Longitudinal Validation: While content validity is established, the paper acknowledges that the instrument is at Technology Readiness Level 2 (experimental research on functionality). The authors could explicitly suggest future research on longitudinal validation and reliability testing to ensure the instrument's stability and predictive power over time.

Response: We have incorporated the reviewer’s suggestion into the Discussion section, explicitly highlighting the need for future research on longitudinal validation and reliability testing to assess the instrument’s stability and predictive power over time.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors, This is an important area of research. The issue is presented clearly and the methods chosen to address it are up-to-date and inclusive.  Comments for your consideration are offered to enhance the manuscript and help to increase use and citation of your work. 

1. To continue the inclusive terminology started by using lactating people in the title of your manuscript, I suggest the use of the word parental instead of maternal; birthing person instead of mother; birthing people instead of women or mothers; lactating people instead of lactating women throughout the manuscript, for example page 2 lines 57, 59, 62, 72, 299
2. Page 3, lines 90 - 95, Please add a description of the process by which permission was obtained to use the previously validated rating scales from the authors of each questionnaire: "...the instrument incorporated previously validated questionnaires, including the Medical Outcomes Study Social Support Survey (MOS-SSS) [17], the short Spanish version of the Woman Abuse Screening Tool (WAST) [18], the Perceived Stress Scale (PSS) [19], the Insomnia Severity Index (ISI) [20], and the Minimum Dietary Diversity for Women (MDDW) [21]." Please correct the references for these questionnaires, which are not all correct, for example the PSS was written by Prof Sheldon Cohen.  
3. Page 3, line 110, Please insert the citation for: "...using the ZOPP method."
4. Please use a bilingual person or a professional editing service to correct the English translations.  For example, Page 7, Table 2, Please correct the English translation for: "En caso de tomar medicación regularmente, menciónela" to "If you take regular medication, mention it". Please correct the translation for "Porque no tomo." to "Because I don't take any."  
5. Page 8, line 284, Please correct the translation for: "No tengo pareja" to "I do not have a partner" Please check all of the other translations.  
6. The main concern is the length of time needed to complete the questions. Were the postpartum individuals on the panel asked whether the majority of the target population would complete this 128 item instrument? Was it tested to discover how long it might take the target population to complete? The PSS-10 has is estimated to take 5 to 7 minutes, assuming roughly the same response rate for all 128 items the time needed would range from 64 to 90 minutes. This issue is not adequately discussed: Page 10, lines 383 - 383: "Additionally, the instrument’s length may pose a response burden in time-constrained settings. However, its modular structure and potential for remote self-administration help mitigate this concern."  If you plan to use individual modules, why not simply use the original questionnaires that form the modules? Alternatively, Qualtrics advises that their own data shows significant drop-outs after 12 minutes, or 9 minutes on a mobile phone app. Is it possible to identify key questions for each module for such situations?  

Author Response

Reviewer 2: The authors acknowledge the reviewer’s opinion about the robustness of the article. Every additional suggestion is addressed as follows:

• To continue the inclusive terminology started by using lactating people in the title of your manuscript, I suggest the use of the word parental instead of maternal; birthing person instead of mother; birthing people instead of women or mothers; lactating people instead of lactating women throughout the manuscript, for example page 2 lines 57, 59, 62, 72, 299

Response: We have revised the manuscript throughout to adopt inclusive terminology, replacing terms such as maternal, mother, women, and lactating women with parental, birthing person/people, and lactating people, including the specific instances noted by the reviewer and all other relevant occurrences.

• Page 3, lines 90 - 95, Please add a description of the process by which permission was obtained to use the previously validated rating scales from the authors of each questionnaire: "...the instrument incorporated previously validated questionnaires, including the Medical Outcomes Study Social Support Survey (MOS-SSS) [17], the short Spanish version of the Woman Abuse Screening Tool (WAST) [18], the Perceived Stress Scale (PSS) [19], the Insomnia Severity Index (ISI) [20], and the Minimum Dietary Diversity for Women (MDDW) [21]." Please correct the references for these questionnaires, which are not all correct, for example the PSS was written by Prof Sheldon Cohen.  

Response: The text has been revised to describe the process for obtaining permission to use each of the previously validated questionnaires. All related references have been reviewed and corrected.

• Page 3, line 110, Please insert the citation for: "...using the ZOPP method."

Response: Done following the suggestions made by the reviewer.

• Please use a bilingual person or a professional editing service to correct the English translations.  For example, Page 7, Table 2, Please correct the English translation for: "En caso de tomar medicación regularmente, menciónela" to "If you take regular medication, mention it". Please correct the translation for "Porque no tomo." to "Because I don't take any."  

Response: The manuscript’s English translations have been reviewed and corrected, including the specific examples noted by the reviewer.

• Page 8, line 284, Please correct the translation for: "No tengo pareja" to "I do not have a partner" Please check all of the other translations.  

Response: The translation for “No tengo pareja” has been corrected to “I do not have a partner” as suggested. All other translations in the manuscript have also been reviewed and corrected to ensure accuracy and consistency.

• The main concern is the length of time needed to complete the questions. Were the postpartum individuals on the panel asked whether the majority of the target population would complete this 128 item instrument? Was it tested to discover how long it might take the target population to complete? The PSS-10 has is estimated to take 5 to 7 minutes, assuming roughly the same response rate for all 128 items the time needed would range from 64 to 90 minutes. This issue is not adequately discussed: Page 10, lines 383 - 383: "Additionally, the instrument’s length may pose a response burden in time-constrained settings. However, its modular structure and potential for remote self-administration help mitigate this concern."  If you plan to use individual modules, why not simply use the original questionnaires that form the modules? Alternatively, Qualtrics advises that their own data shows significant drop-outs after 12 minutes, or 9 minutes on a mobile phone app. Is it possible to identify key questions for each module for such situations?  

Response: The length of the instrument and the potential for a response burden were critical points of discussion within the research team and among the Delphi panel experts. With this in mind, the goal was to develop an instrument that, while comprehensive in scope, was also as concise as possible. We understood that a balance had to be struck between gathering sufficient data and minimizing the time commitment for participants. During the pre-design phase, five team members completed the pilot version of the instrument, with completion times ranging from 20 to 30 minutes. This provided an initial, realistic estimate of the time required. 

During the cognitive interviews, all six postpartum lactating people were fully informed about the study’s objective, gave their informed consent, and were made aware of the estimated completion time and the length of the questionnaire. Importantly, they were offered the option to take a break on multiple occasions but chose to complete the instrument in a single session without interruption. When asked at the end if they felt it was too long or if they were fatigued, they expressed satisfaction with having completed it.

In regards to the modular structure, the group chose this format because of its easier interpretability for the user. And the decision not to use the original, full-length questionnaires were deliberate and well-considered. No single, validated instrument covered the full spectrum of variables we deemed essential for comprehensively assessing the health of postpartum lactating people. Therefore, with guidance from our expert panel and a thorough review of the literature, we developed and combined modules to address these specific gaps. For example, to evaluate social connections, we used two distinct instruments: the MOSS and the short version of the WAST. For the diet module, given the complexity of the variable, we integrated components from several sources, including the MDD-W and specific questions on infusions and other food items adapted from other works.
The instrument’s length is a potential limitation. This is discussed more precisely in the manuscript. Nonetheless, the time needed to complete the questions was below 40 minutes, and all postpartum individuals completed the instrument. These issues have been clarified in Results and Discussion sections.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

This is an important area of research. Best wishes for your further work.