Integrating the Principles of Reverse Logistics into Circular Economy Strategies: A Mixed-Method Study of Small and Medium-Sized Enterprises

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript “Integrating the Principles of Reverse Logistics into Circular Economy Strategies: A Mixed‑Method Study of Small and Medium‑Sized Enterprises” is well aligned with Sustainability’s scope and offers useful insight into the drivers and barriers SMEs face when adopting reverse‑logistics (RL) practices in a circular‑economy (CE) context. The mixed‑methods design—systematic literature review (SLR) plus six expert interviews—adds depth and triangulation. With the refinements listed below, the paper will be ready for publication.

1. The Introduction recognises that SME‑specific RL factors are “under‑explored” . Please be more explicit about how the present study advances prior work (e.g., by integrating SLR categories with fresh interview evidence, or by proposing a new framework).
2. Some success‑factor categories (e.g., “good organisation” vs. “alignment with objectives”) seem redundant (Table 4). Consider merging or re‑labelling for parsimony.
3. The paper gives the search string and inclusion criteria  but does not report how each screening stage reduced the pool (e.g., reasons for exclusion at full‑text stage). Expand Table 2 or the PRISMA figure to include concrete counts/justifications.
4. Provide an interview guide summary, sector background of the six experts, and how data saturation was assessed .
5. Describe how intercoder agreement was ensured when applying Kuckartz’s qualitative content‑analysis method.
6. Insert a few illustrative quotations from the interviews (anonymised) to give readers first‑hand evidence behind key themes (e.g., high investment cost, lack of AI infrastructure).
7. Figure/Table formatting.

• Figure 1 (modified PRISMA) is blurred and the axis labels within the flow diagram are hard to read—please provide a higher‑resolution version.
• Combine Tables 3 and 4 into one compact matrix to ease comparison. Use consistent tense and parallel phrasing.

8. Relate emergent categories to established adoption or capability theories (e.g., Resource‑Based View, Technology‑Organisation‑Environment), which would elevate the academic contribution.
9. The current discussion restates findings; add 2‑3 actionable points for policymakers (e.g., targeted subsidies, simplified administrative procedures) and for SME managers (e.g., quick‑win digital tools for RL tracking).
10. The study rightly acknowledges qualitative scope limits . Please:

• Identify potential bias from the German‑speaking sample and suggest how subsequent studies could incorporate cross‑regional or longitudinal designs.
• Clarify whether the six experts represent different manufacturing/service subsectors, which affects transferability.

Author Response

The improvements made by Reviewer 1 are highlighted in yellow.
Comment 1: The Introduction recognises that SME‑specific RL factors are “under‑explored” . Please be more explicit about how the present study advances prior work (e.g., by integrating SLR categories with fresh interview evidence, or by proposing a new framework).
Answer1: In response, we have made it clearer in the introduction that the aim of this study is to contribute to existing literature by providing an empirical analysis of the challenges and success factors specific to SMEs concerning RL. It provides context-sensitive insights, particularly concerning regulatory uncertainty and customer-related barriers, which have received limited attention thus far.

Comment 2:Some success‑factor categories (e.g., “good organisation” vs. “alignment with objectives”) seem redundant (Table 4). Consider merging or re‑labelling for parsimony.
Answer 2: We have revised Tables 4 and 5 by focusing on merging the overlapping entries.

Comment3:The paper gives the search string and inclusion criteria  but does not report how each screening stage reduced the pool (e.g., reasons for exclusion at full‑text stage). Expand Table 2 or the PRISMA figure to include concrete counts/justifications.
Answer3: We expanded the text to show how the pool was reduced at each screening stage, including reasons for full-text exclusions. This adds transparency to the literature selection process.

Comment4:Provide an interview guide summary, sector background of the six experts, and how data saturation was assessed 
Answer4: We clarified the structure of the interview guide and provided more detail on the experts’ sectoral backgrounds. We also stated that theoretical saturation was reached after six interviews, as no substantially new insights emerged. It can be found in the methodology section.

Comment5:Describe how intercoder agreement was ensured when applying Kuckartz’s qualitative content‑analysis method.
Answer5: We agree that intercoder reliability is critical. Following Kuckartz's methodology, we ensured consistency through collaborative category development, joint coding of samples, and consensus discussions to resolve discrepancies in the methodology section.

Comment6: Insert a few illustrative quotations from the interviews (anonymised) to give readers first‑hand evidence behind key themes (e.g., high investment cost, lack of AI infrastructure).
Answer6: The quotes from the expert interviews were incorporated into the full text in an indirect manner to give readers the evidence behind the key themes and support the findings from both theory and literature.

Comment7: Figure/Table formatting.

• Figure 1 (modified PRISMA) is blurred and the axis labels within the flow diagram are hard to read—please provide a higher‑resolution version.
  
  Answer7: We improved table formatting and ensured parallel phrasing across categories. The PRISMA figure was replaced with a higher-resolution version.
• Combine Tables 3 and 4 into one compact matrix to ease comparison. Use consistent tense and parallel phrasing.
  Answer7: Has also been adjusted.

Comment8:Relate emergent categories to established adoption or capability theories (e.g., Resource-Based View, Technology‑Organization‑Environment), which would elevate the academic contribution.
Answer8: While we recognize the value of theoretical frameworks such as the Resource-Based View or the Technology–Organisation–Environment model, our study follows an inductive and exploratory approach. We deliberately refrained from aligning the categories with existing models to allow empirically grounded, SME-specific factors to emerge freely. We see theory-driven generalization as a valuable direction for future research.

Comment9:The current discussion restates findings; add 2‑3 actionable points for policymakers (e.g., targeted subsidies, simplified administrative procedures) and for SME managers (e.g., quick‑win digital tools for RL tracking).
Answer9: In the revised version, we added concrete recommendations for policymakers, SME managers, and researchers. These are now integrated at the end of the conclusion section.

Comment10:The study rightly acknowledges qualitative scope limits . Please:

• Identify potential bias from the German‑speaking sample and suggest how subsequent studies could incorporate cross‑regional or longitudinal designs.
• Clarify whether the six experts represent different manufacturing/service subsectors, which

Answer10: We expanded the limitation section to reflect the geographical focus on German-speaking countries, the exclusion of certain sectors (e.g., agriculture), and the cross-sectional design. These boundaries are now clearly acknowledged, along with suggestions for future cross-regional and longitudinal studies. This can be found in the discussion.

Reviewer 2 Report

Comments and Suggestions for Authors

As it is, even with all my appreciation the whole study appears substantially a review of what other Authors know or think or report about the issue "RL for CE in the domain of SME". Apparently, these sources were given more importance than direct interviews. 

As a logical outcome, in this paper the drawbacks to CE - that have been identified in the great work done on the references - look like being simply listed, not ranked. 

This ends with yielding little guidance when it comes to proposals to smooth difficulties in the hoped-for setup of a RL aimed at recycle.

My suggestion therefore would be to make more of the interviews: 

a- explaining better the questionnaire survey;

b-  stating explicitly whether the "experts" interviewed were entrepreneurs and industrial managers, or not; and in which production sector;

c- using the results of the survey to draw scales of weight of the success / failure factors identified.

Author Response

The improvements made by Reviewer 2 are highlighted in green.
Comment: As it is, even with all my appreciation the whole study appears substantially a review of what other Authors know or think or report about the issue "RL for CE in the domain of SME". Apparently, these sources were given more importance than direct interviews. 

As a logical outcome, in this paper the drawbacks to CE - that have been identified in the great work done on the references - look like being simply listed, not ranked. 

This ends with yielding little guidance when it comes to proposals to smooth difficulties in the hoped-for setup of a RL aimed at recycle.

My suggestion therefore would be to make more of the interviews: 

a- explaining better the questionnaire survey;

b-  stating explicitly whether the "experts" interviewed were entrepreneurs and industrial managers, or not; and in which production sector;

c- using the results of the survey to draw scales of weight of the success / failure factors identified.

Answer:

1. We agree that the integration of the interview material can be strengthened. We have therefore revised the presentation of the interview data, clarified the role and background of the experts, and included references to the frequency of statements to emphasize the practical weight of selected issues. While the literature provides conceptual grounding, the interview findings were essential in identifying practice-relevant priorities and in validating or contrasting the literature results. This comment has already been answered in the comments by reviewer 1.
2. As clarified in the methodology section, the six interviewees were managers and senior staff from SMEs, rather than entrepreneurs. They held positions related to logistics, operations, or sustainability. The companies represented included four manufacturing firms, one logistics provider, and one environmental/recycling service provider. This comment has already been answered in the comments by reviewer 1.
3. Although our study does not employ a formal ranking or weighting system, we have indicated the frequency with which success and failure factors were mentioned in the interviews. This provides a practical overview of which factors are perceived as being particularly influential. In the section on content analysis, we have highlighted this more clearly and included references to these frequencies when presenting the most important results.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper investigates the integration of reverse logistics (RL) into circular economy (CE) strategies within small and medium-sized enterprises (SMEs). It specifically seeks to identify the challenges and success factors that SMEs face in implementing RL within CE frameworks. To do this, the authors adopt a mixed-methods approach, combining a systematic literature review (SLR) with six expert interviews. The findings are categorized into strategic, operational, technological, financial, and human resource dimensions, and highlight both barriers and enabling factors from academic and practitioner perspectives. In my view, the manuscript could merit favorable consideration following changes based on the below comments.

1/ The two methods (SLR and interviews) are presented in parallel. The synthesis between them could be further enhanced. The paper mostly reports convergences. It could also probe into divergences or explains why perspectives may differ. The discussion could include more analytical depth in interpreting why certain challenges or success factors may dominate in practice but not in literature, or vice versa. The authors are encouraged to introduce a more critical comparative analysis between the SLR and expert findings. Highlight contradictions, validate interview themes against literature more thoroughly, and explain discrepancies to enrich the discussion.

2/ The paper references CE and RL concepts. It could engage more with existing theoretical models or frameworks (e.g., absorptive capacity, institutional theory, dynamic capabilities) that could explain SME behavior in CE adoption. The framework organizing the challenges and success factors could go beyond descriptive and include a conceptual underpinning that could generalize the findings. The authors are encouraged to anchor the findings within a broader theoretical model to enhance conceptual clarity and extend the study’s analytical contribution.

3/ The interviews are restricted to German-speaking countries. The implications of this regional focus could be better discussed. Cultural, regulatory, or economic differences could significantly influence the RL-CE relationship. The study excludes certain sectors (e.g., agriculture, food) but does not elaborate on how these exclusions might affect generalizability. The authors are encouraged to include a more nuanced reflection on regional or sectoral limitations and recommend how future studies might address these gaps.

4/ The authors are recommended to clarify that the sample size of six experts, while relatively small, is not uncommon in the literature on expert surveys, by considering recent literature including but not limited to: https://doi.org/10.1016/j.tre.2024.103753; https://doi.org/10.1016/j.omega.2016.02.003. The added discussion would help reassure readers of the methodological validity and strengthen the credibility of the findings within the context of existing research norms.

5/ Regulatory issues are acknowledged in both the literature and interviews as a significant barrier. They could be analyzed in depth. Taxonomy of policy types (e.g., incentives vs mandates) or specific regulations could be provided. The paper misses an opportunity to assess how existing policy environments help or hinder RL in SMEs. The authors are encouraged to dedicate a focused subsection to regulatory challenges and their implications. Consider mapping types of supportive versus restrictive policy frameworks or integrating a policy analysis into the future research agenda. If it is beyond the scope of current work, then the authors are suggested to add this discussion in the manuscript as part of future research work.

Author Response

The improvements made by Reviewer 3 are highlighted in blue.
Comment 1: The two methods (SLR and interviews) are presented in parallel. The synthesis between them could be further enhanced. The paper mostly reports convergences. It could also probe into divergences or explains why perspectives may differ. The discussion could include more analytical depth in interpreting why certain challenges or success factors may dominate in practice but not in literature, or vice versa. The authors are encouraged to introduce a more critical comparative analysis between the SLR and expert findings. Highlight contradictions, validate interview themes against literature more thoroughly, and explain discrepancies to enrich the discussion.

Answer 1: In response, we have revised the discussion section to better highlight contrasts between the literature and expert insights. While the initial analysis emphasized convergences, we now explicitly address cases where findings diverge—particularly regarding regulatory uncertainty, customer behavior, and the role of digital technologies. This enhanced comparative analysis provides greater analytical depth and contextual interpretation of why certain factors may be more prominent in academic versus practitioner discourse.

Comment 2: The paper references CE and RL concepts. It could engage more with existing theoretical models or frameworks (e.g., absorptive capacity, institutional theory, dynamic capabilities) that could explain SME behavior in CE adoption. The framework organizing the challenges and success factors could go beyond descriptive and include a conceptual underpinning that could generalize the findings. The authors are encouraged to anchor the findings within a broader theoretical model to enhance conceptual clarity and extend the study’s analytical contribution.

Answer 2: We acknowledge the relevance of theoretical frameworks such as absorptive capacity or dynamic capabilities. However, we deliberately chose an exploratory, inductive approach to allow empirically grounded, practice-based categories to emerge without imposing predefined models. We see theoretical integration as a valuable next step for future research.

Comment 3: The interviews are restricted to German-speaking countries. The implications of this regional focus could be better discussed. Cultural, regulatory, or economic differences could significantly influence the RL-CE relationship. The study excludes certain sectors (e.g., agriculture, food) but does not elaborate on how these exclusions might affect generalizability. The authors are encouraged to include a more nuanced reflection on regional or sectoral limitations and recommend how future studies might address these gaps.

Answer 3: We have included it together with a comment from reviewer 1, which was the same. We have expanded the limitations section to reflect how the regional and sectoral focus may affect the generalizability of our findings. Regulatory frameworks, market maturity, and cultural attitudes towards sustainability may differ significantly across countries or sectors. We now also suggest how future research could address these limitations through cross-national and sector-specific comparative studies.

Comment 4: The authors are recommended to clarify that the sample size of six experts, while relatively small, is not uncommon in the literature on expert surveys, by considering recent literature including but not limited to: https://doi.org/10.1016/j.tre.2024.103753; https://doi.org/10.1016/j.omega.2016.02.003 . The added discussion would help reassure readers of the methodological validity and strengthen the credibility of the findings within the context of existing research norms.

Answer 4: Thank you for pointing this out. We clarified that our sample size aligns with established practices for expert interviews in similar qualitative studies. References supporting this are now included in the methodology section.

Comment 5: Regulatory issues are acknowledged in both the literature and interviews as a significant barrier. They could be analyzed in depth. Taxonomy of policy types (e.g., incentives vs mandates) or specific regulations could be provided. The paper misses an opportunity to assess how existing policy environments help or hinder RL in SMEs. The authors are encouraged to dedicate a focused subsection to regulatory challenges and their implications. Consider mapping types of supportive versus restrictive policy frameworks or integrating a policy analysis into the future research agenda. If it is beyond the scope of current work, then the authors are suggested to add this discussion in the manuscript as part of future research work.

Answer 5: We agree that regulatory frameworks play a central role in enabling or hindering reverse logistics adoption. However, a detailed typology of policy instruments (e.g., incentives vs. mandates) was beyond the scope of this exploratory study. In response to your suggestion, we have added a reflection in the conclusion that highlights this gap and encourages future research to systematically investigate the impact of different policy types and regulatory contexts on SME behavior in circular economy implementation.

Round 2

Reviewer 3 Report

Comments and Suggestions for Authors

Most of my previous round comments have been adequately addressed. The references section needs to be revised as per the journal's format requirements. For instance, some of the references are missing doi, journal name, and other elements.

Author Response

Comments 1: Most of my previous round comments have been adequately addressed. The references section needs to be revised as per the journal's format requirements. For instance, some of the references are missing doi, journal name, and other elements.

Response 1: Thank you for your feedback. I have updated the references section in line with the journal's formatting requirements, adding all the missing elements, including the DOI, journal name and other necessary details.

Round 3

Reviewer 3 Report

Comments and Suggestions for Authors

All of my previous round comments have been adequately addressed. The manuscript merits acceptance in my view.