Review Reports

We thank the reviewer for this valuable suggestion, which has helped us improve the clarity and transparency of the manuscript.

Comment

Section

Response

Reading the title of the article "Development and psychometric validation of the Scale of Sexuality and Attitudes toward the Use of Contraceptive Methods in Students" I expected to learn some facts on students sexuality and those attitudes mentioned.

Title and abstract

We thank the reviewer for this thoughtful comment. We agree that the original title could lead to the expectation of a broader descriptive analysis of students’ sexuality and attitudes.

However, the primary aim of this study is the development and psychometric validation of a measurement instrument, rather than an in-depth exploration of sexual behaviours or attitudes at a population level.

To address this concern and improve clarity, we have revised the title to reflect the study's methodological focus. The new title is:

“Development and Psychometric Validation of the Attitudes Toward Contraceptive Use Scale (ACUS) in University Students.”

We believe that this revised title more accurately represents the scope and objectives of the research and avoids potential misinterpretation.

I would propose to introduce all items in the "results". It is important to know what are the questions and what are the answers

Results

We thank the reviewer for this valuable suggestion, which has helped us to improve the clarity and transparency of the manuscript.

In the revised version, we have incorporated the full set of items from the final ACUS scale into the main manuscript (Table 4). This allows readers to clearly identify the content of each item and better understand the construct being measured.

Additionally, we have expanded the results section (Section 3.4) to provide a more detailed description of item-level findings. Specifically, we now present the mean and standard deviation for each item and include a clearer interpretation of the response patterns, highlighting which items reflect more favourable or less favourable attitudes toward contraceptive use.

 We believe these modifications improve the instrument's interpretability and practical applicability.

We sincerely thank Reviewer 2 for the careful and constructive evaluation of our manuscript. We greatly appreciate these detailed comments, which have helped us improve the study's conceptual clarity, methodological precision, and reporting quality. In the revised version, we have addressed all points raised and made substantial changes to the title, abstract, introduction, methods, results, discussion, and references.

Comment

Section

Response

Observations: The title mentions "Scale of Sexuality and Attitudes...", but the validated instrument is only the Attitude Scale (ACUS). There is a conceptual inconsistency between "Sexuality" and "Attitudes toward Contraceptive Use".

Suggestion: Reduce it and align it with the actual content, for example "Development and Psychometric Validation of the Attitudes Toward Contraceptive Use Scale (ACUS) in University Students". This improves conceptual accuracy and internal coherence.

Title

We thank the reviewer for this important observation. We agree that the original wording of the title could suggest a broader construct than the one actually assessed in this study. Since the validated instrument specifically measures attitudes toward contraceptive use, we have revised the title to ensure full conceptual accuracy and internal coherence.

The new title is:

“Development and Psychometric Validation of the Attitudes Towards Contraceptive Use Scale (ACUS) in University Students.”

It is mentioned that the instrument can "identify knowledge gaps", but the scale measures attitudes, not knowledge. The "Aldrich model" is mentioned, but then the results also mention the "Rasch model" (it should be clarified whether the Rating Scale Model or the Partial Credit Model was used). The wording could be more technical in the psychometric part.

 It is suggested to replace "identify knowledge gaps" with identify less favorable attitudinal profiles. It could be clearly specified: "Rasch Rating Scale Model (Andrich model)". Include the procedure for deleting items.

Abstract

We agree with the reviewer. This wording was imprecise. In the revised manuscript, we have replaced the expression “identify knowledge gaps” with “identify less favourable attitudinal profiles toward contraceptive use” throughout, particularly in the Abstract, Discussion, and Conclusions.

There is redundancy in the paragraph on adolescence (lines 32–36 and 47–51) that is repeated almost verbatim. One must be eliminated.

The need for the instrument is well justified, but there is a lack of greater differentiation between instruments of knowledge and instruments of attitudes. Explicitly cite an internationally validated instrument to show the specific gap.

Introduction

We thank the reviewer for noticing this duplication. The repeated paragraph has been removed, and the Introduction has been revised for conciseness and better flow. This redundancy was indeed present in the submitted version.

 We agree with this suggestion. In the revised Introduction, we have strengthened the theoretical distinction between instruments assessing knowledge and those assessing attitudes, emphasising that these are related but conceptually different constructs. We have also incorporated internationally validated examples of attitudinal instruments in sexual health to justify better the specific gap addressed by ACUS and to clarify the novelty of our contribution.

I observe a conceptual inconsistency: Aldrich vs Rasch. It is mentioned: "Aldrich model" and then "Rasch model". It should be clarified whether Andrich's model (Rating Scale Model) is a polytomic Rasch model. It is suggested to use a single consistent name: Rasch Rating Scale Model (Andrich model)

Methodology

We thank the reviewer for identifying this issue. First, we corrected the typographical error: the manuscript incorrectly referred to the “Aldrich model” instead of the Andrich model. In the revised version, we now use a single, technically precise denomination throughout the manuscript:
“Rasch Rating Scale Model (Andrich model)”.

We also clarified in the Methods section that the final analysis was conducted using the Rasch Rating Scale Model for polytomous items with a common response structure across all items. This revision improves conceptual and psychometric precision.

With respect to one-dimensionality, EFA is used and then again EFA in construct validity. Thus, there is methodological redundancy. It is suggested, in the first part, to justify one-dimensionality to apply Rasch. In section 3.3 avoid repeating analysis and reformulate as: Additional evidence of construct validity was obtained through exploratory factor analysis...

Methodology

We appreciate this observation and agree that the distinction between the two analyses needs to be made clearer. In the revised manuscript, we now differentiate these two stages more explicitly. In the psychometric assumptions section, exploratory dimensionality is presented as preliminary evidence to justify the application of the Rasch model. In Section 3.3, we now state that additional evidence of construct validity was examined using exploratory factor analysis. This reformulation reduces redundancy and improves methodological coherence.

With respect to the use of "Principal Components" it is indicated that the "Principal Components method" was used. For factorial validation, Principal Axis Factoring or Maximum Likelihood should be used. PCA is not strictly common factor analysis.

Methodology

We thank the reviewer for this methodological clarification. We agree that Principal Components Analysis is not the optimal approach for extracting common factors in construct validation. Therefore, in the revised version, we have corrected the description of the extraction method and used more appropriate terminology consistent with common factor analysis. Where applicable, we have revised the text to reflect exploratory factor analysis more rigorously.

The KMO value is low-moderate (KMO = 0.725 / 0.758), it does not correspond to a value of excellent, but acceptable. Therefore, it should be described as acceptable sampling adequacy. Do not "adequate" without qualification.

Methodology/Results

We agree with the reviewer. In the revised manuscript, KMO values are now described as indicating acceptable sampling adequacy, rather than using stronger wording. This change has been made in both the Methods and Results sections.

DIF in Table 3: Item 12: p = 0.04. Bonferroni α = 0.0042. It should be made explicit that although item 12 showed p = 0.04, it did not reach the adjusted significance threshold (α = 0.004). Currently it is ambiguous.

Results

We thank the reviewer for this relevant observation. We have revised the Results section to explicitly state that although item 12 showed a nominal p-value of 0.04, this value did not reach the Bonferroni-adjusted significance threshold. Therefore, it was not considered evidence of significant differential item functioning. This point is now clearly stated to avoid ambiguity.

Regarding the psychometric results, in Infit/outfit there is inconsistency between values in the table and report in the text. The text states: infit and outfit values remained within acceptable limits (0.6–1.4), but Table 2 contains outfits: 1.66, 1.55 and 1.51. This contradicts the text. It should be corrected and qualified: Although a few items slightly exceeded the optimal range, none surpassed the broader acceptable interval (0.5–1.5).

Results

We agree and thank the reviewer for identifying this inconsistency. The text has been corrected. In the revised version, we now state that although a small number of items slightly exceeded the optimal range, none showed severe misfit and all remained within, or very close to, the broader acceptable interval typically considered in Rasch analysis. We also qualified the interpretation of items 4, 5, and 6 accordingly.

The explained variance of 41.3% is not particularly high for a one-dimensional scale. It should be interpreted with caution: explaining a moderate proportion of variance.

Results

We agree. In the revised manuscript, we now describe this result more cautiously, indicating that the first factor explained a moderate proportion of variance, which is compatible with a predominantly unidimensional structure but should not be overstated.

In Reliability, a Cronbach α = 0.829 and Rasch person reliability = 0.81 is reported. It would be interesting to add: Omega coefficient or explain why alpha is reported if IRT is used

Results

We appreciate this comment. In the revised manuscript, we clarify that Cronbach’s alpha was reported as a conventional complementary index of internal consistency, given its wide use in validation studies. In contrast, Rasch person reliability was used as the model-based reliability indicator. We also note this as a methodological complement rather than as the primary psychometric evidence. We will include McDonald’s omega as a supplementary reliability coefficient.

The discussion is well connected to literature. It shows good conceptual integration. It can be improved by adding a more critical reflection on the aspects of limitation due to social desirability bias, possible ceiling effect (high mean: 41.55/60) and a mostly female sample (78%). Currently the discussion is more descriptive than critical.

Discussion

We thank the reviewer for this valuable suggestion. The Discussion has been expanded to include a more critical appraisal of the study limitations, specifically:

●      the possibility of social desirability bias due to the self-reported nature of responses on a sensitive topic;

●      the possibility of a ceiling effect, considering the relatively high mean total score;

●      the predominance of female participants, which may affect the representativeness of attitudinal variability.

These issues are now explicitly acknowledged in the revised limitations section.

It is necessary to mention that confirmatory validation (CFA) was not performed and convergent or discriminant validity was not evaluated. Nor was functioning analyzed by sexual orientation. On the other hand, the test–retest subsample size was small (n=44).

Limitations

We agree and have expanded the limitations section accordingly. We now explicitly state that:

●      confirmatory factor analysis was not performed.

●      convergent and discriminant validity were not evaluated.

●      measurement invariance was not examined according to sexual orientation.

●      the test–retest subsample was relatively small.

We also indicate these aspects as priorities for future research.

“Have receive formation” → Have received training

“Specific formation” → Specific training

Some names with typos (Ovsyeyeynko / Ovsyeyenko).

Spaces before references.

Duplicate DOIs or repeated links.

Formal aspects

We thank the reviewer for these careful editorial observations. All language issues, typographical inconsistencies, author name spelling errors, formatting problems in references, and duplicate DOI/link entries have been revised and corrected throughout the manuscript.

To increase the likelihood of acceptance: Clarify the IRT framework in greater technical depth. Add figure from the Wright Map in better resolution. Better justify the choice of the Rasch model over 2PL. Add targeting analytics (mean person vs mean item location). Finally, to include greater reflection on intercultural applicability.

Strategic recommendations for publication

We thank the reviewer for these excellent suggestions. In the revised manuscript:

●      we have clarified the IRT framework in greater technical detail, specifying the use of the Rasch Rating Scale Model (Andrich model);

●      we have improved the presentation of the Wright Map and ensured better figure quality.

●      we have further justified the use of the Rasch approach, highlighting its suitability for instrument development focused on invariant measurement, item-person comparability, and interpretability;

●      where possible, we have added a more explicit comment on targeting between person and item locations;

●      we have expanded the Discussion to acknowledge that intercultural applicability requires future cross-cultural validation studies before broader use in other populations.

Reviewer 3

We sincerely thank Reviewer 3 for the positive and constructive evaluation of our manuscript. We appreciate the recognition of the methodological rigour and relevance of the topic. We have carefully addressed all comments and believe the revised version has been substantially strengthened in its theoretical grounding, methodological transparency, and practical applicability.

Comment

Section

Response

The manuscript entitled “Development and psychometric validation of the Scale of Sexuality and Attitudes toward the Use of Contraceptive Methods in Students” addresses a relevant topic for public health, sexual education, and the promotion of responsible sexual behaviors among young populations. This focus is particularly important in university settings.

A notable strength of the study is the use of a brief 12-item instrument, as well as the assessment of its psychometric properties using Item Response Theory, which adds methodological rigor.

General

We thank the reviewer for the positive assessment of our manuscript and for highlighting its relevance and methodological strengths. We appreciate these constructive comments, which have helped us further improve the manuscript.

The theoretical justification of the construct is limited. Although the manuscript highlights the importance of attitudes in sexual behavior, a deeper theoretical grounding of the construct “attitudes toward the use of contraceptive methods” is needed. Incorporating well-established frameworks such as the Theory of Planned Behavior or other sexual and reproductive health models would strengthen the conceptual foundation.

Introduction

We thank the reviewer for this valuable suggestion. In the revised manuscript, we have strengthened the theoretical framework underlying the construct of attitudes toward contraceptive use. Specifically, we have incorporated references to established behavioural models, including the Theory of Planned Behavior, to better contextualise attitudes as determinants of behavioural intention and preventive sexual behaviours.

This addition reinforces the conceptual basis of the scale and clarifies the role of attitudes as a mediating component between knowledge and behaviour.

Regarding the instrument, greater clarity is required in the conceptualization of the construct and what exactly the scale measures. While the general development process is described, the procedure for initial item generation is not fully clear. It would be important to specify the following:

-        The sources used for item generation (e.g., literature review, interviews, and expert input).

-        The initial number of items generated.

-        Whether expert judgment was conducted and how it was implemented.

-        The criteria used for item reduction, elimination, or retention.

Methodology

We agree with the reviewer and have expanded the Methods section to improve transparency in the development of the instrument. Specifically, we have clarified:

The sources used for item generation include literature review and theoretical frameworks on sexual attitudes and contraception.

The initial number of items generated was 29.

The role of expert judgment, including the evaluation of clarity and relevance using Aiken’s V coefficient.

The criteria for item reduction include content validity thresholds, redundancy, and psychometric performance in pilot and Rasch analyses.

These additions provide a clearer and more reproducible description of the instrument development process.

Concerning the sample, it should be clearly stated whether it consisted exclusively of nursing students. If so, this represents an important limitation in terms of generalizability, as nursing students may have greater knowledge about sexuality and contraception compared to other university populations. This could influence responses and the structure of the instrument. This limitation should be more explicitly acknowledged and discussed.

Methodology/discussion

We thank the reviewer for this important observation. We now explicitly state in the Methods section that the sample consisted exclusively of nursing students.

Additionally, we have expanded the limitations section to acknowledge that this population may have greater prior knowledge and more favourable attitudes toward contraception, which could influence responses and limit the generalizability of the findings to other university populations.

With respect to the psychometric analysis, it is recommended to specify more clearly the statistical software used. Although the results based on the Rasch (Andrich) model are adequately presented, their interpretation could be expanded, particularly regarding indicators such as person reliability, item reliability, and ICC. Additionally, the authors should clarify the practical implications of these results for the use of the scale in research and applied settings.

Methodology/Results

We have revised the Methods section to clearly specify the statistical software used (JASP and JMetrik).

 In addition, we have expanded the Results and Discussion sections to provide a clearer interpretation of key psychometric indicators, including:

Person reliability, interpreted as the ability of the scale to discriminate between different levels of attitudes among participants.

Item reliability reflects the stability of item difficulty estimates.

Intraclass Correlation Coefficient (ICC) indicates the temporal stability of the instrument.

We have also clarified the practical implications of these indicators for the use of the scale in both research and applied contexts.

In the discussion section, it is necessary to strengthen the comparison with existing instruments that assess sexual attitudes or attitudes toward contraceptive use. Furthermore, the manuscript would benefit from a clearer explanation of the specific contributions of this scale compared to existing tools, as well as its potential applications in sexual education programs and public health research. Currently, the discussion focuses more on psychometric findings than on the applied relevance of the instrument.

Discussion

We agree and have strengthened the Discussion by incorporating a more explicit comparison with existing instruments that assess sexual attitudes or contraceptive-related constructs.

We have also clarified the specific contribution of the ACUS scale, highlighting that it provides:

A brief and psychometrically robust instrument;

A focus specifically on attitudes toward contraceptive use, rather than general sexuality or knowledge;

Applicability in educational and public health interventions, particularly in university settings.

A general revision of the writing is recommended, particularly in the introduction, where some conceptual repetition regarding the importance of sexual education is observed. In addition, the transition between the results and discussion sections could be improved to enhance coherence.

General/Introduction

We thank the reviewer for this observation. The manuscript has undergone a thorough language and style revision. Redundant content in the Introduction has been removed, improving clarity and coherence. This change is consistent with suggestions from other reviewers.

The manuscript should also include a more robust limitations section, addressing aspects such as sampling method and sample homogeneity. Expanding on the practical implications for university sexual education and public health interventions would also strengthen the manuscript.

Discussion

We agree and have substantially expanded the limitations section. In addition to sampling method and homogeneity, we now include:

●      Potential social desirability bias;

●      Possible ceiling effect.

●      Lack of confirmatory factor analysis and convergent/discriminant validity;

●      Limited generalizability beyond nursing students.

Furthermore, we have expanded the practical implications of the scale, emphasising its usefulness for:

●      Designing targeted sexual education interventions;

●      Identifying less favourable attitudinal profiles;

Supporting public health strategies in young populations