Translation and Validation of the Modified A-DIVA Scale to European Portuguese: Difficult Intravenous Access Scale for Adult Patients

Round 1

Reviewer 1 Report

Positives:

1. The manuscript provides a validated Portuguese translation of the Modified A-DIVA This is a contribution to both practitioners and researchers in assessing the potential of difficult intravenous access in Portuguese-speaking medical contexts
2. The methodology for the translation of the scale and the assessment of its psychometric properties (including construct and criterion validity) is clearly explained, followed standard protocols, and yielded convincing evidence of significant linguistic equivalence and predictive power regarding PIVC insertion outcomes.
3. The article is written concisely and systematically, making it easy to read and suitable for a wide audience. The findings can be useful for the development of future research interventions in elaborating the predictive power of the translated scale with larger and more representative samples

Negatives:

1. The manuscript does not fit well with the objectives of the special issue for which it was submitted: “A Focus on Healthcare from the Perspective of Gender, Culture, Management, and the Economy”
2. Portions of the manuscript can be written more clearly and with further details and discussion.
3. Elaboration of the need for Portuguese version of the scale would be helpful in convincing the reader of the valuable contribution of the study.
4. Examples of how the results of the scale (i.e., predicting difficulty in PIVC insertion) lead to specific actions by healthcare providers could be added, further enhancing the contribution of this paper.
5. There is little evidence of any cultural adaptation in the discussion of the translation process or in other sections of the paper. If cultural adaptation was actually observed, then examples should be provided. As the title contains the term “cultural adaptation,” this is a rather important point.
6. The sample is small (100 insertions) and non-representative, in that 92% of the patients were female.
7. Furthermore, the average score for the A-DM scale (which ranges from 0 to 5) was .097 (SD ±19) suggests the majority of patients tested were in the “low risk” or “moderate risk” categories. The number of patients per category is not reported.
8. I suggest collecting a larger and more representative sample before resubmitting, if possible.

Suggestions for the author, by section.

Title:

- Please consider whether or not there is any evidence of cultural adaptation in the translation process. If there is, please discuss more in the article. If not, you might remove this term from the title.

- Please spell out A-DIVA for readers unfamiliar with the scale

Authors:

- F.H.J.v.L.  is not credited in the “Author Contributions” section (lines 247-250).

- There is an author listed in the “Author Contributions” section who is not included in the list of authors (R.VL)

Abstract

- The “background” statement should indicate the necessity of translating the Modified A-DIVA scale to Portuguese, rather than the overall “Objective” of the study.

- I would recommend giving the scale a new name, such as A-DM-P (rather than A-DM). The “P” could be used to indicate the language of the scale, Portuguese. Otherwise, referring to A-DM is unclear in that there may be versions of the scale in other languages.

Keywords:

- “Peripheral” is not an informative keyword.

- “Psychometrics” is too general. I suggest revising to “Scale Psychometric Validation” or something similar.

- “Risk Assessment” is, likewise, too general. I suggest “Risk Assessment for Difficult Intravenous Access” or something similar.

1. Introduction:

- Since the manuscript was submitted to the special issue of “A Focus on Healthcare from the Perspective of Gender, Culture, Management, and the Economy,” mention of international or cultural differences would be expected. For example, three articles are cited [3-5], but no detailed explanation of the differences mentioned is provided. This would be of interest to the reader and strengthen the justification for translating the scale to Portuguese.

- The content from lines 43 through 51 should be supported by appropriate citations, as this paragraph refers to specifics regarding healthcare professionals in the context of PIVC insertion difficulties.

- The final paragraph (lines 69-71) should be expanded to explain why a Portuguese version is necessary. Is there a language barrier that prevents healthcare professionals from assessing risk of complications during PIVC insertion? If so, greater elaboration on this issue should be provided to strengthen your claim that a translation and cultural adaptation of the scale is required.

2. Material and Methods

- Overall, this section clearly describes the procedures. However, it would be interesting to know the language proficiency of the reviewers for different stages of the process (in addition to the professional translators).

- Where was cultural adaptation noted during Phase 1? Please provide some examples. If only linguistic changes were required, then the “cultural adaptation” element does not need to be mentioned.

- In the description of the criterion and construct validity conducted for Phase 2 (page 3, lines 138-139, it would be good to introduce the benchmark scales/measures used. Although they are mentioned in Section 3, a brief introduction here seems appropriate. Furthermore, can you elaborate upon the standards Boateng et al. proposed?

3. Results:

- The titles in Table 1 (Factor and Punctuation?) should be in English. I also recommend that the original scale items (English version) be provided for each of the Portuguese items. To save space, this table could also be merged with Table 3, which reports the inter-rater reliability measures.

- It would be useful to describe the way in which the scale is used by practitioners to identify patients at risk of complications in terms of what actions/techniques they would utilize depending on risk level.

- Table 2 indicates that 92% of the patients were female. This is quite an unbalanced data set. Can you provide some explanation as to why the overwhelming majority of patients were female? As gender is included as a measure for evaluating criterion and construct validity, gender differences must exist. What is the predicted relationship between gender and risk of difficult intravenous access?

- Please provide an explanation of how the A-DIVA scale is scored. For example, 1 point for each positive response (maximum 5 points, minimum 0 points). 0-1 points is low risk, 2-3 points is moderate risk, and 4-5 points is high risk. What interventions would be associated with those different risk levels?

- As mentioned above, the average score for the A-DM scale (which ranges from 0 to 5) was .097 (SD ± 1.19) suggests the majority of patients tested were in the “low risk” or “moderate risk” categories. This should be discussed, and the proportion of patients belonging to each risk category should be described and analyzed.

- Take care to use italics for statistical items, such as p on line 164.

- In terms of factors which are hypothesized to be related to intravenous access difficulty (lines 167-169) a bit more discussion would be helpful. For example, which of these items are most predictive? Why would gender be a factor? What are the differences according to insertion site (even though these factors were not significant)?

- Overall the list of items in Table 4 is quite long. Certainly the several significant findings are sufficient to provide evidence of validity, but can any explanation be provided for the items which did not correlate significantly?

- On line 171, please spell out the full name of ENAV and provide a description.

4. Discussion:

- Be careful in mentioning “cultural adaptation” (line 181) if no examples of this phenomenon can be provided.

- In this section, examples of actions that can be taken by healthcare professionals in response to the risk categories of their patients as determined by the A-DIVA would be appropriate.

5. Conclusions:

- Mentioning examples of “professional-related variables” (line 245) would be useful.

References:

- There are some inconsistencies in the references, such as the use of capitalization for journal article titles (uppercase or lowercase). A few more examples are provided below:

- [6] contains incorrect use of author names

- [7] does not use bold for the date.

- [19] uses all caps for part of the article title.

 

Author Response

Dear Reviewer,

 On behalf of the authors, we deeply appreciate the time and dedication shown in the revision of the manuscript. Several points were raised throughout. We hope that the modifications made are congruent with the revisions proposed. 

 Title:

• After careful discussion between the authors, we agreed to remove "cultural adaptation" from the title and manuscript, since most of the modifications made were language-based and not due to a cultural difference.
• The term "DIVA" patient is widely used in the literature to refer to patients with difficult intravenous access. Nonetheless, reporting to the original scale, we propose "Translation and validation of the Modified A-DIVA Scale to European Portuguese: difficult intravenous access scale for adult patients".

Authors:

• This was a mistake on our end. F.H.J.v.L. and R.VL correspond to the same author. This was corrected in the author contributions section. 

 

Abstract

• Within the 200 word tlimit, we have included more information in the background section.
• Although the authors appreciate the suggestion, this decision derived from the contributions of the experts involved during Phase 1. Moreover, the original author of the A-DIVA and Modified A-DIVA scales agreed with this decision.
• We are unsure if adding the “-P” component would matter, since the order of the scale’s name was changed during the translation process (Modified A-DIVA to A-DIVA Modificada) and this may not happen in other languages.

 

Keywords:

• The terms used were MeSH, probably the reason why they are vague (it should be read as “catheterization, peripheral”). We appreciate and accept the suggestions made.

 

Introduction:

1. Reviewer: Since the manuscript was submitted to the special issue of “A Focus on Healthcare from the Perspective of Gender, Culture, Management, and the Economy,” mention of international or cultural differences would be expected. For example, three articles are cited [3-5], but no detailed explanation of the differences mentioned is provided. This would be of interest to the reader and strengthen the justification for translating the scale to Portuguese.

Answer: The authors appreciate and agree with the reviewer’s suggestion. The sentence was rewritten as “Peripheral intravenous catheter (PIVC) insertion is frequently qualified as a nursing procedure, although this differs between international settings, which may explain the high variability of clinical practices reported in the literature [3–5]. In fact, while nurses are the primary PIVC inserters in countries from Europe (79%), North America (69%) or Asia (84%) [4], other countries such as New Zealand and Australia present higher numbers of PIVC insertion by doctors, technicians or multidisciplinary specialist teams [4,5].”

2. Reviewer: The content from lines 43 through 51 should be supported by appropriate citations, as this paragraph refers to specifics regarding healthcare professionals in the context of PIVC insertion difficulties.

Answer: We fully agree with the reviewer’s suggestion. References were provided that clearly the specifics for healthcare professionals and patients. 

Reviewer: The final paragraph (lines 69-71) should be expanded to explain why a Portuguese version is necessary.

Answer: The last paragraph was rewritten and now includes data from Portuguese studies that evidence high rates of multiple attempts until a PIVC is successfully inserted: It now reads:

To the best of the authors' knowledge, there are no known validated tools used in the early assessment of patients’ peripheral intravenous access in Portugal. This may potentially explain why current studies conducted in Portugal report between two to eight puncture attempts before a successful PIVC insertion in almost a quarter of the study population [16–18]. In fact, if considering the entire period of hospital admission, one study highlighted that an average of five puncture attempts are performed before a successful PIVC insertion, ranging between one and 20 puncture attempts [16]. Instruments like the Modified A-DIVA scale could assist healthcare professionals in Portugal to prospectively identify patients at risk of difficult intravenous access based on easily available clinical data [15], adjusting their approach to PIVC insertion and preserving patients’ peripheral intravenous network. Therefore, this study focused on the translation and validation of the Modified A-DIVA Scale to European Portuguese.

 

Material and Methods

4. Reviewer: Overall, this section clearly describes the procedures. However, it would be interesting to know the language proficiency of the reviewers for different stages of the process (in addition to the professional translators).

Answer: We accept this suggestion. A short description of the invited reviewer’s language proficiency was added that highlights their independent use of the language on a professional level.

5. Reviewer: Where was cultural adaptation noted during Phase 1? Please provide some examples. If only linguistic changes were required, then the “cultural adaptation” element does not need to be mentioned.

Answer: Already answered before, the term “cultural adaptation” was removed throughout the manuscript.

6. Reviewer: In the description of the criterion and construct validity conducted for Phase 2 (page 3, lines 138-139, it would be good to introduce the benchmark scales/measures used. Although they are mentioned in Section 3, a brief introduction here seems appropriate. Furthermore, can you elaborate upon the standards Boateng et al. proposed?

Answer: The only scale used for benchmark was the Venous International Assessment Scale, also undergoing translation and validation. A more detailed description was added as requested. It now reads: The ENAV is a “performance status tool” [20] that allows healthcare professionals to classify the patient’s peripheral intravenous access in five grades based on three comprehensive parameters: i) the number of observable puncture points; ii) PIVC size and ease to perform venipuncture; iii) risk of extravasation or phlebitis [20]. The risk of difficult intravenous access progressively increases in accordance to each grade.

 

Results:

7. Reviewer: The titles in Table 1 (Factor and Punctuation?) should be in English. I also recommend that the original scale items (English version) be provided for each of the Portuguese items. To save space, this table could also be merged with Table 3, which reports the inter-rater reliability measures.

Answer: The table fully represents the results of the translation process, including the headers Factor and Score/Punctuation. Given that this was not clear, we suggest a new version of Table 1, that compares the original scale (left) and translated version to European Portuguese (right).

8. Reviewer: It would be useful to describe the way in which the scale is used by practitioners to identify patients at risk of complications in terms of what actions/techniques they would utilize depending on risk level.

Answer: While we fully agree with the reviewer’s suggestion, this is not the aim of the validation article presented. We acknowledge that this contribution to clinical practice is needed in the discussion section “Likewise, future studies should identify recommendations to clinical practice following the A-DM’s score [12]”. Nonetheless, the authors would like to inform Reviewer 1 that a large prospective observational study with the Modified A-DIVA scale (in European Portuguese) is being conducted and we expect to provide such recommendations based on the patient’s risk level in a near future.

9. Reviewer: Table 2 indicates that 92% of the patients were female. This is quite an unbalanced data set. Can you provide some explanation as to why the overwhelming majority of patients were female? As gender is included as a measure for evaluating criterion and construct validity, gender differences must exist. What is the predicted relationship between gender and risk of difficult intravenous access?

Answer: As mentioned by the reviewer, our sample is mostly female patients. This is due to two reasons: i) pre-surgical patients were included in our study, but only patients that would return to the surgical ward after surgery would be included in our study (in order to follow the PIVC after insertion and monitor related complications and dwell time, as reported); ii) a large number of surgeries performed in the selected clinical setting were due to breast cancer, which mainly affects female patients.

Although gender is referenced in previous articles as a hypothetical risk factor for difficult intravenous access, results regarding gender are not consensual (while others such as age and body mass index are). To be as comprehensive as possible, the authors decided to include this variable in the analysis, although we did not expect significant results given the included sample’s characteristics. To be as transparent as possible, and guide future research with the A-DM scale, we have included the following in the limitations:

Still, study limitations must be addressed, such as the non-probability, consecutive sampling technique used to recruit participants from a specific clinical setting. Further validation studies in different clinical sites and involving specific patient cohorts are needed to attest the A-DM’s transversal applicability. Future studies should test the A-DM’s predictive nature with more comprehensive study samples, allowing for the analysis of its functioning in patients that display hypothetically risk factors for difficult peripheral intravenous access (e.g., gender).

10. Reviewer: Please provide an explanation of how the A-DIVA scale is scored. For example, 1 point for each positive response (maximum 5 points, minimum 0 points). 0-1 points is low risk, 2-3 points is moderate risk, and 4-5 points is high risk. What interventions would be associated with those different risk levels?

Answer: The authors presented the A-DIVA scale and its scoring in the introduction section, lines 70-77. As previously explained, recommendations per risk score are currently being reviewed by the authors based on results from a large observational study and recommendations from international standards of care. The need for such recommendations was highlighted in the discussion section, and the authors intend to proceed with such publication in the near future.  

11. Reviewer: Take care to use italics for statistical items, such as pon line 164.

Answer: We thank the reviewer. Italics are now used for all statistical items.

12. Reviewer: In terms of factors which are hypothesized to be related to intravenous access difficulty (lines 167-169) a bit more discussion would be helpful. For example, which of these items are most predictive? Why would gender be a factor? What are the differences according to insertion site (even though these factors were not significant)?

Overall, the list of items in Table 4 is quite long. Certainly the several significant findings are sufficient to provide evidence of validity, but can any explanation be provided for the items which did not correlate significantly?

Answer: The authors reviewed several articles focused on risk factors and compiled all factors that could be address given the data collected during the initial validation study. Although several risk factors are frequently statistically associated with higher risk of difficult intravenous access (e.g., patient gender, BMI, PIVC caliber, and specific comorbidities such as Diabetes), there is no consensus yet on this topic.

To address the reviewer’s concern, we added on the discussion section the following: “Although a comprehensive list of risk factors was retrieved from the literature and used to test the A-DM’s validity, there is no international consensus on which factors are associated with higher chances of difficult intravenous access [25,26]. This may explain why some of the included patient and procedural variables did not correlate significantly with the A-DM scale (e.g., patient gender, PIVC insertion locations).”

13. Reviewer: On line 171, please spell out the full name of ENAV and provide a description.

Answer: Included in line 155: “Moreover, each nurse also scored the Venous International Assessment (VIA) Scale [20] which is also undergoing a translation and validation process to the Portuguese population (hereby referred to as ENAV scale).”

 

Discussion:

14. Reviewer: Be careful in mentioning “cultural adaptation” (line 181) if no examples of this phenomenon can be provided.

Answer: We appreciate the suggestion. The term was reviewed throughout the manuscript.

15. Reviewer: In this section, examples of actions that can be taken by healthcare professionals in response to the risk categories of their patients as determined by the A-DIVA would be appropriate.

Answer: Thank you for the suggestion. This was address before by the authors (e.g., answer 8 and 10).

 

Conclusions:

16. Reviewer: Mentioning examples of “professional-related variables” (line 245) would be useful.

Answer: We appreciate with the reviewer’s suggestion. Few examples were included in accordance to the variables depicted in the discussion section.

References:

The authors reviewed the references and corrected the found inconsistencies. We deeply appreciate the reviewer’s attention to this section.

Reviewer 2 Report

Reviewing the manuscript entitled, “Translation, cultural adaptation and validation of the Modified A-DIVA Scale to European Portuguese” by Santos-Costa P et al., this is a manuscript focuses on an appropriate translation, cultural adaptation, and verification of the modified A-DIVA scale into European Portuguese. This is extremely interesting and has igerph-friendly content. So, the authors need to response my minor concerns for accepting.

 

The conclusion of abstract is strange. It is inconsistent with the conclusion of the text. The usefulness of the A-DM scale has already been proven, and the conclusion of this manuscript should be that it has been successfully translated into European Portuguese and adapted culturally. Authors need to modify them.

 

The process of Phase 1 is difficult to understand. Authors need to add a figure of phase1.

 

The author's contribution is important in this manuscript. Therefore, Author Contributions should be described in detail.

Author Response

Dear Reviewer,

The authors deeply appreciate the time and dedication shown in the revision of the manuscript. A few points were raised throughout. We hope that the modifications made are congruent with the revisions proposed. 

Reviewer: The conclusion of the abstract is strange. It is inconsistent with the conclusion of the text. The usefulness of the A-DM scale has already been proven, and the conclusion of this manuscript should be that it has been successfully translated into European Portuguese and adapted culturally. Authors need to modify them.

Answer: Thank you for the comment. The abstract conclusion reads: "The A-DM scale is a reliable and valid instrument that can support healthcare professionals and researchers in the early identification of patients at risk of difficult peripheral intravenous access. Future validation studies are needed to test the A-DM scale’s applicability across clinical settings and in different patient cohorts.

The conclusion section reads: "(...) The A-DM scale evidenced respectable reliability and validity properties (...) Future validations studies should be developed across clinical settings and patient cohorts..."

We are unsure of how both sections are inconsistent. Likewise, while robust data has been gathered that supports the original Modified A-DIVA scale's validity and reliability in different clinical settings and specific patient cohorts, the same still needs to be done for the A-DM scale (or the European version of the Modified A-DIVA scale). As an example, the A-DM scale's five factors may not be sensible/adjusted enough to accurately predict difficult intravenous access in patients in septic shock, with upper limb oedema, hypovolaemia or severe dehydration (conditions that are also more likely to be experienced by patients in emergency rooms rather than in pre-surgical settings). Thus, we advise authors to further test the scale before fully implement it in their practice. 

Reviewer: The process of Phase 1 is difficult to understand. Authors need to add a figure of phase 1.

Answer: Thank you for the suggestion. A scheme was added (lines 96-99). 

Reviewer: The author's contribution is important in this manuscript. Therefore, Author Contributions should be described in detail.

Answer: Thank you for the suggestion. Individual contributions were listed according to the CRediT taxonomy (lines 286-289). 

Round 2

Reviewer 1 Report

Response to Authors (from Reviewer 1):

On behalf of the authors, we deeply appreciate the time and dedication shown in the revision of the manuscript. Several points were raised throughout. We hope that the modifications made are congruent with the revisions proposed.

Reply: Thank you for your thorough and thoughtful revisions. I am happy with the revisions made and the current manuscript. Overall, your prompt reply and appropriate revisions, additions, and explanations are appreciated.

1. After careful discussion between the authors, we agreed to remove "cultural adaptation" from the title and manuscript, since most of the modifications made were language-based and not due to a cultural difference.

Reply: This is appreciated, since otherwise the reader would be anticipating discussion of cultural differences.

2. The term "DIVA" patient is widely used in the literature to refer to patients with difficult intravenous access. Nonetheless, reporting to the original scale, we propose "Translation and validation of the Modified A-DIVA Scale to European Portuguese: difficult intravenous access scale for adult patients".

Reply: Thank you for this change. While DIVA is a widely known term in most healthcare settings, the journal attempts to reach a wide audience. Furthermore, by publishing your translation and validation process in an open access journal, you may attract the interest of readers from a variety of fields.

3. Authors: This was a mistake on our end. F.H.J.v.L. and R.VL correspond to the same author. This was corrected in the author contributions section. 

Reply: Corrections noted.

4. Within the 200 word limit, we have included more information in the background section.

Reply:  The sentence regarding the research objective/background of this study was an important addition. The changes to the keywords are also appreciated!

5. Although the authors appreciate the suggestion, this decision derived from the contributions of the experts involved during Phase 1. Moreover, the original author of the A-DIVA and Modified A-DIVA scales agreed with this decision. We are unsure if adding the “-P” component would matter, since the order of the scale’s name was changed during the translation process (Modified A-DIVA to A-DIVA Modificada) and this may not happen in other languages.

Reply: This was only a suggestion for the sake of simplicity and in order to distinguish the Modified A-DIVA original and Portuguese forms in the manuscript. With appropriate contextualization, retaining the same acronym should be fine.

6. Reviewer: Since the manuscript was submitted to the special issue of “A Focus on Healthcare from the Perspective of Gender, Culture, Management, and the Economy,” mention of international or cultural differences would be expected. For example, three articles are cited [3-5], but no detailed explanation of the differences mentioned is provided. This would be of interest to the reader and strengthen the justification for translating the scale to Portuguese.

Answer: The authors appreciate and agree with the reviewer’s suggestion. The sentence was rewritten as “Peripheral intravenous catheter (PIVC) insertion is frequently qualified as a nursing procedure, although this differs between international settings, which may explain the high variability of clinical practices reported in the literature [3–5]. In fact, while nurses are the primary PIVC inserters in countries from Europe (79%), North America (69%) or Asia (84%) [4], other countries such as New Zealand and Australia present higher numbers of PIVC insertion by doctors, technicians or multidisciplinary specialist teams [4,5].”

Reply:  Although brief, the description of the findings from these articles was helpful in explaining why a translated scale would be useful for healthcare workers in the European context, as generalist nurses, rather than specialists, are responsible for the majority of insertions.

7. Reviewer: The content from lines 43 through 51 should be supported by appropriate citations, as this paragraph refers to specifics regarding healthcare professionals in the context of PIVC insertion difficulties.

Answer: We fully agree with the reviewer’s suggestion. References were provided that clearly the specifics for healthcare professionals and patients.

Reply: The citations and references are appreciated!

8. Reviewer: The final paragraph (lines 69-71) should be expanded to explain why a Portuguese version is necessary.

Answer: The last paragraph was rewritten and now includes data from Portuguese studies that evidence high rates of multiple attempts until a PIVC is successfully inserted: It now reads:

To the best of the authors' knowledge, there are no known validated tools used in the early assessment of patients’ peripheral intravenous access in Portugal. This may potentially explain why current studies conducted in Portugal report between two to eight puncture attempts before a successful PIVC insertion in almost a quarter of the study population [16–18]. In fact, if considering the entire period of hospital admission, one study highlighted that an average of five puncture attempts are performed before a successful PIVC insertion, ranging between one and 20 puncture attempts [16]. Instruments like the Modified A-DIVA scale could assist healthcare professionals in Portugal to prospectively identify patients at risk of difficult intravenous access based on easily available clinical data [15], adjusting their approach to PIVC insertion and preserving patients’ peripheral intravenous network. Therefore, this study focused on the translation and validation of the Modified A-DIVA Scale to European Portuguese.

Reply: I believe that this section is much stronger now and definitely highlights the need for research in this area and the contribution of your study.

9. Reviewer: Overall, this section clearly describes the procedures. However, it would be interesting to know the language proficiency of the reviewers for different stages of the process (in addition to the professional translators).

Answer: We accept this suggestion. A short description of the invited reviewer’s language proficiency was added that highlights their independent use of the language on a professional level.

Reply: Thank you for addressing this point.

10. Reviewer: Where was cultural adaptation noted during Phase 1? Please provide some examples. If only linguistic changes were required, then the “cultural adaptation” element does not need to be mentioned.

Answer: Already answered before, the term “cultural adaptation” was removed throughout the manuscript.

Reply: This is appreciated.

11. Reviewer: In the description of the criterion and construct validity conducted for Phase 2 (page 3, lines 138-139, it would be good to introduce the benchmark scales/measures used. Although they are mentioned in Section 3, a brief introduction here seems appropriate. Furthermore, can you elaborate upon the standards Boateng et al. proposed?

Answer: The only scale used for benchmark was the Venous International Assessment Scale, also undergoing translation and validation. A more detailed description was added as requested. It now reads: The ENAV is a “performance status tool” [20] that allows healthcare professionals to classify the patient’s peripheral intravenous access in five grades based on three comprehensive parameters: i) the number of observable puncture points; ii) PIVC size and ease to perform venipuncture; iii) risk of extravasation or phlebitis [20]. The risk of difficult intravenous access progressively increases in accordance to each grade.

Reply: Thank you for this addition. Despite the fact that it is still undergoing translation and validation, the items listed for the evaluation of VIA are excellent benchmarks for developing validity.

12. Reviewer: The titles in Table 1 (Factor and Punctuation?) should be in English. I also recommend that the original scale items (English version) be provided for each of the Portuguese items. To save space, this table could also be merged with Table 3, which reports the inter-rater reliability measures.

Answer: The table fully represents the results of the translation process, including the headers Factor and Score/Punctuation. Given that this was not clear, we suggest a new version of Table 1, that compares the original scale (left) and translated version to European Portuguese (right).

Reply: I find this table much more useful and information. Thank you for the revisions.

13. Reviewer: It would be useful to describe the way in which the scale is used by practitioners to identify patients at risk of complications in terms of what actions/techniques they would utilize depending on risk level.

Answer: While we fully agree with the reviewer’s suggestion, this is not the aim of the validation article presented. We acknowledge that this contribution to clinical practice is needed in the discussion section “Likewise, future studies should identify recommendations to clinical practice following the A-DM’s score [12]”. Nonetheless, the authors would like to inform Reviewer 1 that a large prospective observational study with the Modified A-DIVA scale (in European Portuguese) is being conducted and we expect to provide such recommendations based on the patient’s risk level in a near future.

Reply: I appreciate the fact that this is outside of the scope of the present article. I am also glad to know that you are in the process of collecting data in response to this important element of clinical practice. I look forward to seeing the results in your future publications.

14. Reviewer: Table 2 indicates that 92% of the patients were female. This is quite an unbalanced data set. Can you provide some explanation as to why the overwhelming majority of patients were female? As gender is included as a measure for evaluating criterion and construct validity, gender differences must exist. What is the predicted relationship between gender and risk of difficult intravenous access?

Answer: As mentioned by the reviewer, our sample is mostly female patients. This is due to two reasons: i) pre-surgical patients were included in our study, but only patients that would return to the surgical ward after surgery would be included in our study (in order to follow the PIVC after insertion and monitor related complications and dwell time, as reported); ii) a large number of surgeries performed in the selected clinical setting were due to breast cancer, which mainly affects female patients.

Reply: Thank you for your explanation and this additional background information. I am curious as to whether or not you would consider this information regarding your sample important enough to share briefly in the revised manuscript. I will leave that choice up to you; however, as a reader, I would certainly be eager to know.

Although gender is referenced in previous articles as a hypothetical risk factor for difficult intravenous access, results regarding gender are not consensual (while others such as age and body mass index are). To be as comprehensive as possible, the authors decided to include this variable in the analysis, although we did not expect significant results given the included sample’s characteristics. To be as transparent as possible, and guide future research with the A-DM scale, we have included the following in the limitations:

Still, study limitations must be addressed, such as the non-probability, consecutive sampling technique used to recruit participants from a specific clinical setting. Further validation studies in different clinical sites and involving specific patient cohorts are needed to attest the A-DM’s transversal applicability. Future studies should test the A-DM’s predictive nature with more comprehensive study samples, allowing for the analysis of its functioning in patients that display hypothetically risk factors for difficult peripheral intravenous access (e.g., gender).

Reply: The comprehensiveness of the list of potential risk factors is appreciated. The fact that several items were significantly correlated is sufficient to establish validity (by Boateng et al.’s standards). The current limitations provided in the revised version of the manuscript seem sufficient to address any concerns I may have had.

15. Reviewer: Please provide an explanation of how the A-DIVA scale is scored. For example, 1 point for each positive response (maximum 5 points, minimum 0 points). 0-1 points is low risk, 2-3 points is moderate risk, and 4-5 points is high risk. What interventions would be associated with those different risk levels?

Answer: The authors presented the A-DIVA scale and its scoring in the introduction section, lines 70-77. As previously explained, recommendations per risk score are currently being reviewed by the authors based on results from a large observational study and recommendations from international standards of care. The need for such recommendations was highlighted in the discussion section, and the authors intend to proceed with such publication in the near future. 

Reply: My apologies for overlooking your previous explanation. It is certainly sufficient in terms of explaining the administration of the scale. I just expected to see discussion of the scale scoring in the Materials and Methods section.

16. Reviewer: Take care to use italics for statistical items, such as p on line 164.

Answer: We thank the reviewer. Italics are now used for all statistical items.

Reply: Thank you for your attention to detail. Very few typos were noted throughout the manuscript.

17. Reviewer: In terms of factors which are hypothesized to be related to intravenous access difficulty (lines 167-169) a bit more discussion would be helpful. For example, which of these items are most predictive? Why would gender be a factor? What are the differences according to insertion site (even though these factors were not significant)? Overall, the list of items in Table 4 is quite long. Certainly the several significant findings are sufficient to provide evidence of validity, but can any explanation be provided for the items which did not correlate significantly?

Answer: The authors reviewed several articles focused on risk factors and compiled all factors that could be address given the data collected during the initial validation study. Although several risk factors are frequently statistically associated with higher risk of difficult intravenous access (e.g., patient gender, BMI, PIVC caliber, and specific comorbidities such as Diabetes), there is no consensus yet on this topic.

To address the reviewer’s concern, we added on the discussion section the following: “Although a comprehensive list of risk factors was retrieved from the literature and used to test the A-DM’s validity, there is no international consensus on which factors are associated with higher chances of difficult intravenous access [25,26]. This may explain why some of the included patient and procedural variables did not correlate significantly with the A-DM scale (e.g., patient gender, PIVC insertion locations).”

Reply: I can understand the complexity and potential contradictions which results from the use of a comprehensive list. Your current version of the manuscript is sufficient in describing this issue and stating that the number of significant correlations found was evidence of the validity of the measure, which was the purpose of Table 4.

18. Reviewer: On line 171, please spell out the full name of ENAV and provide a description.

Answer: Included in line 155: “Moreover, each nurse also scored the Venous International Assessment (VIA) Scale [20] which is also undergoing a translation and validation process to the Portuguese population (hereby referred to as ENAV scale).”

Reply: Noted. Thanks.

19. Reviewer: Be careful in mentioning “cultural adaptation” (line 181) if no examples of this phenomenon can be provided.

Answer: We appreciate the suggestion. The term was reviewed throughout the manuscript.

Reply: Thank you.

20. Reviewer: In this section, examples of actions that can be taken by healthcare professionals in response to the risk categories of their patients as determined by the A-DIVA would be appropriate.

Answer: Thank you for the suggestion. This was address before by the authors (e.g., answer 8 and 10).

Reply: Noted. Thanks for the detailed responses above.

21. Reviewer: Mentioning examples of “professional-related variables” (line 245) would be useful.

Answer: We appreciate with the reviewer’s suggestion. Few examples were included in accordance to the variables depicted in the discussion section.

Reply: These are sufficient to give the reader a sense of what direction future research might take. Thank you.

22. References: The authors reviewed the references and corrected the found inconsistencies. We deeply appreciate the reviewer’s attention to this section.

Reply: I still notice one common inconsistency: the capitalization of journal article titles. I believe the proofreading department will deal with these.

23. Additional comment: Figure 1 (which was added for this version of the manuscript) contains re-underlined text in the images. This indicates that the language of the text editor used for proofreading” was likely set to Portuguese, which resulted in the red mark-up (interpreted as grammatical errors). Please ensure that the journal office has an editable version of the file (not a screenshot) or that a version without the red lines is provided. Overall, I do not personally feel that this overview chart contributes to the article’s readability, as the figure is text-heavy with small font. Perhaps another format of the table (more vertical, less horizontal) could be considered.