Analysis of Antecedents and Their Influences on Sustainable Public Procurement: A Structural Equation Modeling Approach

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

 

1. Please expand the literature review by including more international references, for example from Europe or Asia, to better contextualize the Brazilian studies against global trends.
2. Please add more critical analysis of the literature, highlighting research gaps and potential controversies related to the antecedents of SPP.
3. The description of the sample selection criteria and the snowball sampling technique needs to be expanded. How were potential biases associated with the method addressed?
4. Have the authors considered providing a more detailed description of the preparation and validation of the survey? Were any modifications made to the questionnaires?
5. Please provide a more comprehensive discussion of the results, with critical reflection on the limitations of the SEM model and the implications of the low CFI and NFI values.
6. The interpretation of the results should be supplemented by comparisons with other empirical studies from the global literature.
7. Please emphasize the limitations arising from the sample being restricted to HEIs in Brazil and the use of snowball sampling.
8. In the conclusions, please provide more concrete and practical recommendations, such as specific steps, training suggestions, and procedural changes.
9. Please suggest directions for future research.

Author Response

Dear Editor and Reviewers,

Thank you very much for giving us the opportunity to revise and resubmit the paper. We want to express our sincere gratitude to the anonymous reviewers for helping us to improve the paper.

The manuscript was revised according to the comments and suggestions made by the reviewers. We have substantially revised the whole paper to address the issues raised by the reviewers. We hope that the revised paper will be suitable for publication in The Sustainability Journal. However, please do not hesitate to let us know if further modifications are needed.

Thank you very much for your consideration of our paper. We are looking forward to hearing from you.

Yours Sincerely,

Authors

 

Reviewers' comments:

Reviewer 1: 

 

1. Please expand the literature review by including more international references, for example from Europe or Asia, to better contextualize the Brazilian studies against global trends.

Answer: We are very grateful for your contribution to improving the paper. In Chapter 1 of the Introduction, we included the percentages of public procurement spending in some countries as a proportion of their GDP, as shown in lines 48 to 51, in red. In Section 2, “Theoretical framework and research hypotheses”, we separate the definitions by constructs and then present the hypothesis test to facilitate the reader's understanding and establish a more robust relationship between the constructs. Throughout Section 2, we expanded the literature, including examples of countries, to better contextualize the relationship with Brazil. We highlighted the initiatives between the countries in the text, in red and located in lines 156 to 162; 177 to 180; 184 to 188; 197 to 201; 211 to 220; 229 to 231; 240 to 245; 257 to 260; 293 to 297; 342 to 347; 372 to 377; 390 to 393; 407 to 410; 413 to 429.

2. Please add more critical analysis of the literature, highlighting research gaps and potential controversies related to the antecedents of SPP

Answer: We are very grateful for your contribution to improving the paper. In Chapter 1, “Introduction”, we included information about the research gap. In red in the text, in lines 91 to 94. In Chapter 2, “Theoretical framework and research hypotheses”, we expanded the analysis of the literature, with the inclusion of some gaps identified in the literature. In the text, these analyses can be verified in lines 148 to 155, 240 to 245, 293 to 297, 303 to 305, 314 to 316, 320 to 325, 400 to 406.

3. The description of the sample selection criteria and the snowball sampling technique needs to be expanded. How were potential biases associated with the method addressed?

Answer: We are very grateful for your contribution to improving the paper. In Chapter 3, “Method”, we expanded the explanation of how the snowball technique was used and how potential biases were addressed. In the text, this explanation is in red on lines 450 to 467.

4. Have the authors considered providing a more detailed description of the preparation and validation of the survey? Were any modifications made to the questionnaires?

Answer: We are very grateful for your contribution to improving the paper. In Chapter 3, “Method”, we included a more detailed description of the research preparation and validation, as well as the necessary adjustments to the questionnaire, which were carried out by experts in the field before the pilot test. We also reported that there were no difficulties or suggestions for improvement from the participants. This analysis is included in the text, in red, and lines 473 to 486.

5. Please provide a more comprehensive discussion of the results, with critical reflection on the limitations of the SEM model and the implications of the low CFI and NFI values.

Answer: We are very grateful for the contribution to improving the paper. In Chapter 4, “Results and discussions”, we provide a more in-depth analysis of the results in general and justify the maintenance of the proposed model despite indexes such as NFI and CFI having values below the ideal. We also offer suggestions for future research to promote improvements in the model. This analysis is included in the text, in red, in lines 642 to 651.

6. The interpretation of the results should be supplemented by comparisons with other empirical studies from the global literature.

Answer: We are very grateful for their contribution to improving the paper. In Chapter 4, “Results and discussion”, we provide a more in-depth analysis of the results and make comparisons with empirical studies from the global literature. This analysis is included in the text, in red, in lines 680 to 689; 695 to 704; 713 to 728; 740 to 751; 770 to 774.

7. Please emphasize the limitations arising from the sample being restricted to HEIs in Brazil and the use of snowball sampling

Answer: We are very grateful for the contribution to improving the paper. In Chapter 4, “Results and Discussion”, we included an analysis of the limitations resulting from the sample being restricted to HEIs in Brazil, as well as the restriction of the sample having been created using the snowball technique. This analysis is included in the text, in red, in lines 804 to 812.

8. In the conclusions, please provide more concrete and practical recommendations, such as specific steps, training suggestions, and procedural changes.

Answer: We are very grateful for the contribution to improving the paper. In Chapter 4, “Results and discussion”, we present a proposal for improvements based on the literature and the application of the proposed model. In Chapter 5, Conclusion, we reinforce these proposals with more concrete examples. This proposal is included in the text, in red, on lines 758 to 766 and 787 to 803.

9. Please suggest directions for future research.

Answer: We are very grateful for your contribution to improving the paper. In Chapter 5, “Conclusion”, we included suggestions for future research. This suggestion is included in the text, in red, in lines 813 to 817.

To adapt the formatting to the Sustainability Journal, we have reorganized the references in the order they appear in the text. We would like to thank you in advance for all your support and contributions to improving the paper.

Best regards

Authors

 

Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

This paper investigates antecedents of sustainable public procurement (SPP) in Brazilian higher education institutions (HEIs) through structural equation modeling (SEM), identifying actors, strategies, purposes, and barriers as key constructs. It contributes an empirically validated model demonstrating that actors, strategies, and purposes positively influence sustainability outcomes, while barriers negatively affect purposes. The study addresses gaps in SPP literature by focusing on social dimensions in a developing context and proposing actionable insights for HEIs to enhance procurement sustainability, offering policymakers and managers a systemic framework to align procurement practices with sustainable development goals.

(1) The Cronbach’s alpha values for constructs like ASPP (0.564) and PSPP (0.563) fall below the recommended threshold of 0.7, raising concerns about internal consistency. How do the authors justify retaining these constructs despite low reliability, and what steps were taken to address measurement error?  
(2) Model fit indices (CFI=0.828, NFI=0.708) suggest suboptimal alignment with the data. What modifications or alternative models were explored to improve fit, and why were they excluded?  
(3) The sample is geographically skewed (70.3% from Southeast Brazil). How might regional biases affect the generalizability of findings to other Brazilian regions or developing contexts with differing socioeconomic conditions?  
(4) The barrier construct (BSPP) shows a weak negative influence (β=0.29) on purposes. Why might this effect be so limited, and how do cultural or institutional factors in Brazilian HEIs explain this result compared to barriers reported in other studies?  
(5) Several references (e.g., Santos et al., 2025; Lagstrom & Ek Osterberg, 2024) are dated 2024–2025, implying they are unpublished or in press. Are these sources peer-reviewed, and how does their provisional status impact the validity of the literature review?  
(6) The questionnaire (Appendix A) includes broad terms like “sustainable development” without operational definitions. How was respondent interpretation controlled, and was pilot testing used to refine item clarity?  
(7) The study highlights Brazil’s legal framework but does not analyze how specific procurement regulations (e.g., price-centric bidding laws) uniquely constrain SPP in HEIs compared to other sectors. What legal nuances might limit the model’s applicability beyond HEIs?

Author Response

Dear Editor and Reviewers,

Thank you very much for giving us the opportunity to revise and resubmit the paper. We want to express our sincere gratitude to the anonymous reviewers for helping us to improve the paper.

The manuscript was revised according to the comments and suggestions made by the reviewers. We have substantially revised the whole paper to address the issues raised by the reviewers. We hope that the revised paper will be suitable for publication in The Sustainability Journal. However, please do not hesitate to let us know if further modifications are needed.

Thank you very much for your consideration of our paper. We are looking forward to hearing from you.

Yours Sincerely,

Authors

Reviewers' comments:

Reviewer 2: 

1. The Cronbach’s alpha values for constructs like ASPP (0.564) and PSPP (0.563) fall below the recommended threshold of 0.7, raising concerns about internal consistency. How do the authors justify retaining these constructs despite low reliability, and what steps were taken to address measurement error?

Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussions”, we analyzed and justified the permanence of the constructs despite Cronbach's Alpha being below the ideal limit and the possible measurement errors. This analysis and justification are included in the text, in red, and lines 579 to 593.

2. Model fit indices (CFI=0.828, NFI=0.708) suggest suboptimal alignment with the data. What modifications or alternative models were explored to improve fit, and why were they excluded?

Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussions”, we present an analysis and justification for maintaining the current model despite the indices not following ideal patterns. We also add an agenda for future research aimed at improving the model. In the text, these analyses can be verified in lines 643 to 647 and 648 to 651.

3. The sample is geographically skewed (70.3% from Southeast Brazil). How might regional biases affect the generalizability of findings to other Brazilian regions or developing contexts with differing socioeconomic conditions?

Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussion”, we acknowledge that the sample is asymmetric, as well as the biases inherent in this sample. However, we demonstrate how we managed to minimize this adverse effect and propose suggestions for future research to improve the generalizability of the results. In the text, this explanation is in red on lines 553 to 559.

4. The barrier construct (BSPP) shows a weak negative influence (β=0.29) on purposes. Why might this effect be so limited, and how do cultural or institutional factors in Brazilian HEIs explain this result compared to barriers reported in other studies?

 Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussion”, we include information on possible reasons why the barriers construct does not have a strong negative influence on the proposals, especially in the context of Brazilian higher education institutions (HEIs). This analysis is included in the text, in red, and lines 713 to 728.

 

5. Several references (e.g., Santos et al., 2025; Lagstrom & Ek Osterberg, 2024) are dated 2024–2025, implying they are unpublished or in press. Are these sources peer-reviewed, and how does their provisional status impact the validity of the literature review?

Answer: We are very grateful for the contribution to improving the paper. In Chapter 2, "Theoretical Framework and Research Hypotheses," we outline how the literature review was conducted, including peer-reviewed updates, to deepen our understanding of the frontier of knowledge in SPP. This analysis is included in the text, in red, on lines 115 to 137.

6. The questionnaire (Appendix A) includes broad terms like “sustainable development” without operational definitions. How was respondent interpretation controlled, and was pilot testing used to refine item clarity?

Answer: We are very grateful for their contribution to improving the paper. In Chapter 3, “Methods,” we provide information on how the questionnaire was distributed, the pilot test, and the demographic profile of the respondents. This analysis is included in the text, in red, in lines 496 to 500.

7. The study highlights Brazil’s legal framework but does not analyze how specific procurement regulations (e.g., price-centric bidding laws) uniquely constrain SPP in HEIs compared to other sectors. What legal nuances might limit the model’s applicability beyond HEIs?

Answer: We are very grateful for the contribution to improving the paper. In Chapter 4, “Results and Discussion”, we included information on the new public procurement legislation in Brazil, as well as regulatory nuances that restrict SPP, and how they may limit the implementation of SPP models. This analysis is included in the text, in red, in lines 740 to 751.

To better understand the constructs, their relationships, and their influences, Chapter 2, Theoretical Framework and Research Hypotheses, expands the literature by dividing the constructs and separating the research hypotheses to provide more theoretical robustness to the model.

To adapt the formatting to the Sustainability Journal, we have reorganized the references in the order they appear in the text. We would like to thank you in advance for all your support and contributions to improving the paper.

Best regards

Authors

 

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The research addresses an important gap in sustainable public procurement literature, particularly in the context of developing countries. The use of structural equation modeling (SEM) provides a robust quantitative approach to examining relationships between constructs. The focus on Higher Education Institutions (HEIs) in Brazil offers valuable insights into an underexplored sector.

Major Concerns:

1. Theoretical Framework and Literature Review: The theoretical foundation appears fragmented and lacks depth. The literature review fails to provide a comprehensive synthesis of existing knowledge on sustainable public procurement antecedents. The conceptual framework seems to emerge abruptly without sufficient theoretical justification for the proposed relationships. The authors need to strengthen the theoretical underpinnings by providing a more rigorous review of relevant theories and establishing clearer linkages between constructs.

2. Methodology Issues: Several methodological concerns need addressing. The sample size of 165 respondents, while meeting minimum SEM requirements, raises questions about statistical power and generalizability. The non-probabilistic sampling approach using snowball technique introduces potential selection bias that is inadequately addressed. The survey instrument appears to lack proper validation procedures, and the pre-test with only 43 respondents is insufficient for a robust instrument validation.

3. Construct Validity and Reliability: The reliability and validity indicators present concerning results. Several constructs show Cronbach's alpha values below the acceptable threshold of 0.7, and convergent validity (AVE) values are consistently below the recommended 0.5 threshold. The factor loadings for some variables fall below acceptable levels, suggesting potential issues with construct validity. These fundamental psychometric problems undermine the credibility of the entire analysis.

4. Data Analysis and Interpretation: The model fit indices (CFI = 0.828, NFI = 0.708) indicate poor model fit, suggesting the proposed model does not adequately represent the underlying data structure. The authors acknowledge these limitations but fail to provide adequate solutions or alternative model specifications. The interpretation of results proceeds despite these significant model fit issues.

5. Limitations and Generalizability: The study's focus on Brazilian HEIs severely limits generalizability to other contexts, sectors, or countries. The authors acknowledge this limitation but fail to adequately discuss how cultural, institutional, and regulatory differences might affect the findings' applicability elsewhere.

Author Response

Dear Editor and Reviewers,

Thank you very much for giving us the opportunity to revise and resubmit the paper. We want to express our sincere gratitude to the anonymous reviewers for helping us to improve the paper.

The manuscript was revised according to the comments and suggestions made by the reviewers. We have substantially revised the whole paper to address the issues raised by the reviewers. We hope that the revised paper will be suitable for publication in The Sustainability Journal. However, please do not hesitate to let us know if further modifications are needed.

Thank you very much for your consideration of our paper. We are looking forward to hearing from you.

Yours Sincerely,

Authors

Reviewers' comments:

Reviewer 3: 

 

1. Theoretical Framework and Literature Review:The theoretical foundation appears fragmented and lacks depth. The literature review fails to provide a comprehensive synthesis of existing knowledge on sustainable public procurement antecedents. The conceptual framework seems to emerge abruptly without sufficient theoretical justification for the proposed relationships. The authors need to strengthen the theoretical underpinnings by providing a more rigorous review of relevant theories and establishing clearer linkages between constructs.

Answer: We are very grateful for your contribution to improving the paper. In Chapter 2, “Theoretical Framework and Research Hypotheses,” we included information from the systematic literature review (SLR) conducted, expanded the literature, and organized it by construct to facilitate understanding. To demonstrate the relationship between the constructs, we included a more detailed hypotheses research section to provide more robustness to the theoretical model. This analysis and justification are included in the text, in red, and lines 115 to 440.

2. Methodology Issues: Several methodological concerns need addressing. The sample size of 165 respondents, while meeting minimum SEM requirements, raises questions about statistical power and generalizability. The non-probabilistic sampling approach using snowball technique introduces potential selection bias that is inadequately addressed. The survey instrument appears to lack proper validation procedures, and the pre-test with only 43 respondents is insufficient for a robust instrument validation.

Answer: We are very grateful for your contribution to improving the paper. In Chapter 3, “Methods,” we included a justification for the sample size in the text, located on lines 504 to 513. Regarding snowball sampling and its potential biases, these are justified in the text, specifically in lines 450 to 467. Regarding the validation of the research and the pre-test, justification is provided in the text, lines 468 to 486.

3. Construct Validity and Reliability:The reliability and validity indicators present concerning results. Several constructs show Cronbach's alpha values below the acceptable threshold of 0.7, and convergent validity (AVE) values are consistently below the recommended 0.5 threshold. The factor loadings for some variables fall below acceptable levels, suggesting potential issues with construct validity. These fundamental psychometric problems undermine the credibility of the entire analysis.

Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussion,” we justify the permanence of constructs with Cronbach's Alpha below the ideal value. In the text, the justification follows in lines 579 to 593. For factor loadings below the perfect value, the justification is provided in the text, lines 570 to 577. For AVE values below the ideal value, we justify this in the text, lines 601 to 610.

4. Data Analysis and Interpretation:The model fit indices (CFI = 0.828, NFI = 0.708) indicate poor model fit, suggesting the proposed model does not adequately represent the underlying data structure. The authors acknowledge these limitations but fail to provide adequate solutions or alternative model specifications. The interpretation of results proceeds despite these significant model fit issues

 Answer: We are very grateful for your contribution to improving the paper. In Chapter 4, “Results and Discussion,” we include a justification for maintaining the proposed model despite the suboptimal NFI and CFI indices. We also present a suggestion for future research to improve the model. This analysis is included in the text, in red, and lines 642 to 651.

5. Limitations and Generalizability:The study's focus on Brazilian HEIs severely limits generalizability to other contexts, sectors, or countries. The authors acknowledge this limitation but fail to adequately discuss how cultural, institutional, and regulatory differences might affect the findings' applicability elsewhere.

Answer: We are very grateful for the contribution to improving the paper. In Chapter 4, "Results and Discussions," we include an analysis of the limitations of the research application in other contexts and suggest adaptations to the model, considering institutional, cultural, and regulatory differences. This analysis is included in the text, in red, on lines 767 to 774.

To adapt the formatting to the Sustainability Journal, we have reorganized the references in the order they appear in the text. We would like to thank you in advance for all your support and contributions to improving the paper.

Best regards

Authors

 

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Thank you for submitting the revised version of the article. After reviewing the changes, I am pleased to confirm that I accept the manuscript in its current form

Reviewer 2 Report

Comments and Suggestions for Authors

I have no further comments.

Reviewer 3 Report

Comments and Suggestions for Authors

I think this version is acceptable for publication