Analysis and Verification Results of Manual Inspection of Pavement Condition Index

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Submitted paper is an interesting study to compare a group or road condition inspectors. The approach with defining a road section, dividing it into several section and let inspectors independently and repeatedly to assess the pavement conditions and calculate PCI is interesting. If this is then repeated after the additional training it provides some extra feedback how effective such training is. What is a bit question to me if the initial assessment/evaluation done with 3-4 months repeatedly on same sections cannot be in some limited extend influenced also by small progress of some distresses. This is not reflected in the process described by the paper, but might be in my opinion relevant. 

Author Response

Comment 1:

Submitted paper is an interesting study to compare a group or road condition inspectors. The approach with defining a road section, dividing it into several section and let inspectors independently and repeatedly to assess the pavement conditions and calculate PCI is interesting. If this is then repeated after the additional training it provides some extra feedback how effective such training is. What is a bit question to me if the initial assessment/evaluation done with 3-4 months repeatedly on same sections cannot be in some limited extend influenced also by small progress of some distresses. This is not reflected in the process described by the paper, but might be in my opinion relevant. 

Response 1:

Thank you for your valuable comment. In the early stage of this study, we conducted a pilot test with inspections repeated two days apart. However, we found that inspectors tended to recall specific distress locations, which influenced their assessments and reduced objectivity.Therefore, in the formal study, we adopted a monthly inspection schedule to avoid memory-based interference. The selected road sections were located in low-traffic urban areas, and visual inspections before each measurement round confirmed stable surface conditions.Additionally, Taiwan’s climate between February and May is generally mild, further reducing the likelihood of rapid deterioration.This clarification has been added to Section 2.1, page 2, and marked in red.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The paper applsci-3514634 Analysis and verification results of manual inspection of Pavement Condition Index follows a logical structure with a clear introduction, methodology, results, discussion, and conclusion. However, some sections could benefit from more explicit connections between paragraphs. For example, transitions between "Materials and Methods" and "Results" could be smoother. Some subsection headings are very long (e.g., "Verification Methods for the Indicators" could simply be "Verification Methods"). The "Discussion" and "Conclusion" sections slightly overlap. The discussion already summarizes key findings, so the conclusion should focus more on broader implications and recommendations rather than reiterating findings.

The language is generally clear and technical, but there are grammatical inconsistencies. Some sentences are too long and would benefit from restructuring to enhance readability. For example:
"By analyzing the actual inspection data from multiple inspectors, we evaluate their impact on PCI scores" can be modified as: "This study analyzes inspection data from multiple inspectors to evaluate their impact on PCI scores." Some minor typing errors (e.g., “inspec-tion” should be “inspection”).

More references to recent works (last 5 years) would strengthen the argument and demonstrate engagement with current research trends.

Figure 1a is incomplete. Use larger fonts and better alignment for clarity.

Figure 2 does not add much to the text beyond what is described. It may be redundant.

AVG in Table 1 is not defined.

In the conclusions section the recommendation about a CV threshold for repeatability and MRE for accuracy is valuable but should be linked more explicitly to practical applications. The paper does not discuss potential limitations of the study, such as the small sample size of inspectors or external factors influencing manual inspections. Moreover, future work should be explicitly mentioned about automated PCI evaluation, rather than a general suggestion for further research.

Comments on the Quality of English Language

The language is generally clear and technical, but there are grammatical inconsistencies. Some sentences are too long and would benefit from restructuring to enhance readability. For example:
"By analyzing the actual inspection data from multiple inspectors, we evaluate their impact on PCI scores" can be modified as: "This study analyzes inspection data from multiple inspectors to evaluate their impact on PCI scores." Some minor typing errors (e.g., “inspec-tion” should be “inspection”).

Author Response

Comments 1: some sections could benefit from more explicit connections between paragraphs. For example, transitions between "Materials and Methods" and "Results" could be smoother. Some subsection headings are very long (e.g., "Verification Methods for the Indicators" could simply be "Verification Methods"). The "Discussion" and "Conclusion" sections slightly overlap. The discussion already summarizes key findings, so the conclusion should focus more on broader implications and recommendations rather than reiterating findings.
Response 1: Thank you for your detailed feedback. We have revised the transitions between sections, especially between “Materials and Methods” and “Results,” to improve logical flow. Subsection headings have been shortened for clarity—for example, “Verification Methods for the Indicators” has been renamed “Verification Methods.” Additionally, we revised the Conclusion section to reduce overlap with the Discussion and focused more on practical implications, recommendations, and the unique contributions of the study. 

Comments 2:The language is generally clear and technical, but there are grammatical inconsistencies. Some sentences are too long and would benefit from restructuring.
Response 2:Thank you for this observation. We have carefully reviewed the manuscript and revised grammatically inconsistent or overly long sentences to improve clarity and readability. Examples include rewording certain statements into more concise forms and standardizing terminology.

Comments 3:More references to recent works (last 5 years) would strengthen the argument and demonstrate engagement with current research trends.
Response 3:Thank you for the suggestion. We have reviewed and updated the references section to include more recent works where applicable. However, it is important to note that relatively few studies in the past five years have specifically addressed manual PCI inspection validation. This highlights the originality and necessity of our research. The newly added references can be found in the Introduction and Discussion sections and are marked in red in the revised manuscript.

Comments 4:Figure 1a is incomplete. Use larger fonts and better alignment for clarity.
Figure 2 does not add much to the text beyond what is described. It may be redundant.
AVG in Table 1 is not defined.
Response 4:Thank you for your constructive comments regarding the figures and table clarity.
We have revised Figure 1a by increasing the font size and improving element alignment to enhance readability.
For Figure 2, we reviewed its purpose and clarified in the text that it serves as a visual reference for the segmentation of road sections discussed in Section 2.3. As it aids in understanding the study area layout, we have retained the figure.
Regarding Table 1, we clarified the meaning of "AVG" in both the table caption and a footnote.

• The row-wise AVG refers to the average PCI score across the four inspectors for each road unit.
• The column-wise AVG in the bottom row refers to the average score provided by each inspector across all road sections.

All corresponding revisions are highlighted in red in the manuscript.

Comments 5:In the conclusions section the recommendation about a CV threshold for repeatability and MRE for accuracy is valuable but should be linked more explicitly to practical applications. The paper does not discuss potential limitations of the study, such as the small sample size of inspectors or external factors influencing manual inspections. Moreover, future work should be explicitly mentioned about automated PCI evaluation, rather than a general suggestion for further research.
Response 5:Thank you for these thoughtful and constructive suggestions. We have revised both the Discussion and Conclusion sections to clearly explain how the proposed CV (≤0.1) and MRE (≤10%) thresholds can be applied in practice—particularly in QC/QA protocols for road maintenance agencies that rely on manual inspection. We also added a new paragraph discussing potential limitations of the study, including the limited number of inspectors and the influence of external environmental factors. Finally, the future research direction has been clarified to emphasize the extension of this validation framework to automated or AI-based PCI inspection technologies. These revisions are reflected in Sections 4 and 5 and are marked in red in the revised manuscript.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Applied sciences- Round 1

Title: Analysis and verification results of manual inspection of Pavement Condition Index

 

Summary:

This paper evaluates Pavement Condition Index (PCI) through ASTM D6433-23 methodology. The authors assessed the effect of inspector training to statistically compare the PCI values on the manual inspection. This research scope is significant due to the necessity of prioritizing investments in pavement management and maintenance.  However, the paper lacks scientific content, and there is no clear contribution to the technical or research advancements in the field. The results are insufficient, and further analysis is recommended.

 

Article review:

The article does not have appropriate references, as it does not have any cited references.

The authors only used one road with 570 meters and 4 inspectors to statistically evaluate accuracy and consistency, it is believed that this limited data must have adversely affected the calculations. Also, the scientific sound and hypothesis tested in the data validation section is not appropriately designed.

Most of the recent contributions in this research topic are involving the use of artificial intelligent, automatic inspections, and development of correlations. The results presented in this paper do not provide an advancement in the current knowledge. The scope of the necessity of training an inspector before the field survey is obvious and does not bring any technical advancements in the field.

 

Specific comments:

1. Abstract revision: The abstract needs to be rewritten to provide a more comprehensive overview of the work. It is recommended to include a clear description of the methodology, the principal results obtained, and the most significant conclusions derived from the study.
2. Grammar and English quality: The English is appropriated and understandable. However, avoid using phrases in first person of plural (“we”).
3. Introduction: The introduction should focus on discussing key studies directly related to the topic, to provide a clearer context for the objectives of this research. No previous paper or discussion is presented in this paper.
4. Missing citations: Figure 1 refers to ASTM D6433-23, therefore it should be accompanied by an appropriate reference to support its inclusion.
5. Missing context: In line 77, it is referred to a literature review. However, it is not presented in the article. In line 80, it is referring to “roads”. However, only one road was evaluated.
6. Method: In line 141, more details about the manual inspection system should be provided.
7. Discussion of the results: The discussion section should be improved and supported by the results presented in the paper. It would be beneficial to compare and contextualize the findings with relevant literature to strengthen the academic rigor of the discussion. Additionally, the authors are encouraged to compare their findings with similar studies in the field, as this will provide context and allow readers to better assess the significance of the results in relation to existing research.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English is appropriated and understandable. However, avoid using phrases in first person of plural (“we”).

Author Response

Comments 1: Abstract revision: The abstract needs to be rewritten to provide a more comprehensive overview of the work. It is recommended to include a clear description of the methodology, the principal results obtained, and the most significant conclusions derived from the study.
Response 1: Thank you for this suggestion. We have revised the abstract to provide a more comprehensive and structured overview, including a brief description of the methodology, the main results (such as improvements in CV and MRE after training), and practical conclusions for future application.

Comments 2:Grammar and English quality: The English is appropriated and understandable. However, avoid using phrases in first person of plural (“we”).
Response 2:Thank you. In response to this and Reviewer #2’s related language comment, we revised the manuscript to remove unnecessary use of first-person pronouns. Phrases such as “we evaluate” were replaced with “this study evaluates” or other objective alternatives.

Comments 3:Introduction: The introduction should focus on discussing key studies directly related to the topic, to provide a clearer context for the objectives of this research. No previous paper or discussion is presented in this paper.
Response 3:Thank you for your comment. We agree that providing a stronger literature background can help clarify the positioning of our study. While we conducted a comprehensive literature review, we found that few recent studies within the past five years have directly addressed the validation of manual PCI inspections, particularly in the context of inspector training and reliability evaluation. Most recent research in this field has focused on automated or AI-based pavement assessment. This scarcity of recent literature highlights the need and originality of our study, which focuses on manual inspection verification.

Comments 4:Missing citations: Figure 1 refers to ASTM D6433-23, therefore it should be accompanied by an appropriate reference to support its inclusion.
Response 4:Thank you for the observation. We have added the full reference to ASTM D6433-23 in both the figure caption and the reference list to clarify its source. The update is applied in Figure 1 caption and References section and marked in red.

Comments 5:Missing context: In line 77, it is referred to a literature review. However, it is not presented in the article. In line 80, it is referring to “roads”. However, only one road was evaluated.
Response 5:Thank you for pointing out these inconsistencies. We have revised the expression in line 77 to clarify that the study background is based on existing standards and selected literature, rather than a full systematic literature review. In addition, we corrected “roads” to “road” in line 80 to accurately reflect that only one road (Zhongda Road) was used in the experiment.
These edits have been applied to Section 2.2 and are highlighted in red in the revised manuscript.

Comments 6:Method: In line 141, more details about the manual inspection system should be provided.
Response 6:Thank you for the helpful suggestion. We agree that the original description of the manual inspection system was too general. To address this, we have expanded the paragraph in line 155 to include specific information about how the system functions in the field. This includes details on its web-based interface, mobile data entry, real-time cloud synchronization, PCI calculation logic, and photographic documentation. The updated description is located in Section 2.4.1.

Comments 7:Discussion of the results: The discussion section should be improved and supported by the results presented in the paper. It would be beneficial to compare and contextualize the findings with relevant literature to strengthen the academic rigor of the discussion. Additionally, the authors are encouraged to compare their findings with similar studies in the field, as this will provide context and allow readers to better assess the significance of the results in relation to existing research.
Response 7:Thank you for this valuable comment. In response, we have revised the Discussion section (Section 4) to better contextualize our findings. The updated text more clearly explains the implications of our results and how the proposed validation indicators (CV and MRE) address practical challenges in manual PCI inspections. While we chose not to cite additional external studies, the revised discussion compares our results with commonly observed practices and highlights how this study contributes a standardized and quantifiable framework for evaluating manual inspection quality. These revisions enhance both the academic and practical relevance of the study. The updated content appears on page 12, and has been marked in red in the revised manuscript.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

the paper can be accepted

Author Response

Comments 1: 
The paper can be accepted.

Response 1: 
We sincerely thank the reviewer for their positive feedback and recommendation to accept the manuscript. We appreciate your time and support in reviewing our work.

Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

Applied sciences- Round 2

Title: Analysis and verification results of manual inspection of Pavement Condition Index

 

Overview: The authors improved the writing of the manuscript, adding more information on methods and discussion of the results.

 

Some comments follow:

1. The article has 4 cited references in the written text, but it has 25 references at the “references” section. And all of them are in the same paragraph. Therefore, there is a lack of proper scientific content.
2. The article still has no clear contribution to the technical or research advancements in the field. The scope of the necessity of training an inspector before the field survey is obvious and does not bring any technical advancements in the field. Also, the use of only one road with 570 meters is statistically insufficient for evaluating accuracy and consistency.
3. The authors added Figures 3 and 4, which are screenshots of the system software. However, they are difficult to understand.

Author Response

Comments 1: 
The article has 4 cited references in the written text, but it has 25 references at the “references” section. And all of them are in the same paragraph. Therefore, there is a lack of proper scientific content.
Response 1: 
Thank you for your valuable feedback. We have thoroughly revised the manuscript to improve the citation structure and scientific support.We have distributed the 25 references throughout the manuscript and linked them to the appropriate sections, such as the introduction, methodology, discussion, and validation procedures. The revised citations now support the background literature, methodology selection, and result interpretation more effectively, enhancing the overall scientific rigor of the paper.

Comments 2: 
The article still has no clear contribution to the technical or research advancements in the field. The scope of the necessity of training an inspector before the field survey is obvious and does not bring any technical advancements in the field. Also, the use of only one road with 570 meters is statistically insufficient for evaluating accuracy and consistency.
Response 2: 
Thank you for your constructive feedback. We respectfully clarify that the technical contribution of this study lies in the establishment of a practical and quantifiable validation framework for manual PCI inspections, which has not been clearly defined in existing literature. While inspector training is indeed common, few studies have systematically measured its effect on both repeatability and accuracy using statistical indicators. Our study not only demonstrates the measurable impact of training but also proposes practical quality control thresholds (Coefficient of Variation ≤ 0.1, Mean Relative Error ≤ 10%) for manual PCI assessments—filling a gap in current standards and offering guidance for both manual inspections and automated system calibration.
Regarding the dataset, although the study area is limited to a 570-meter section, it was carefully divided into 12 separate pavement units, each with diverse distress types and repeated measurements before and after training. This design allows for statistically meaningful comparisons while controlling for external variables such as weather or surface aging, thereby ensuring data reliability. We have clarified these points in the revised manuscript (see Sections 1, 3.1, and 5).

Comments 3: 
The authors added Figures 3 and 4, which are screenshots of the system software. However, they are difficult to understand.
Response 3: 
Thank you for your valuable comment. In response, we have revised Figures 3 and 4 to improve their clarity and readability. Visual enhancements were made to the figures to make the user interface and functional components more distinguishable. Additionally, the figure captions have been revised to better describe each subfigure and improve the overall understanding of the system workflow. We hope these improvements address your concerns and make the figures easier to interpret.

Author Response File: Author Response.docx