Predictive Markers and Self-Perceived Health in Adolescents: An Exploration Through a School-Based Public Health Survey

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This study presents a timely and relevant contribution to the field of adolescent health, particularly in its focus on gender-sensitive public health strategies. The research is clearly presented, methodologically sound, and grounded in empirical data that is statistically well-analyzed.

The manuscript possesses several strengths. The objectives are well established, and the design is appropriate for the study objectives.

Data collection methods are properly described, with thoughtful ethical processes. Statistical analysis is rigorous, and the presentation of results is organized and simple to understand. Tables are brief and expressive, facilitating the understanding of key findings by the reader. 

Most importantly, the study reveals significant gender differences in health behaviors and provides viable suggestions for community-based interventions.

There are, however, some aspects in which the manuscript can be improved.

The research would be better by explicitly stating its hypotheses or research questions in the introduction, to provide more direction. 

Although the discussion helpfully outlines the findings, it could more actively critically discuss the limitations of the study particularly the reliance on self-report data, the cross-sectional design, and the potential for cultural specificity to limit generalizability.

There is a bit of repetition in the discussion and conclusion chapters that could be removed to improve conciseness. A more general connection to international health trends would also render the findings more applicable beyond the Spanish context. 

Overall, the manuscript is a valuable contribution to the public health literature. 

Author Response

We sincerely appreciate your positive and constructive feedback. We have incorporated the following improvements:

The research question has been further clarified in the introduction.

The discussion section has been expanded to more thoroughly address methodological limitations, including the use of self-reported data, the cross-sectional design, and potential cultural constraints.

Redundancies between the discussion and conclusions have been reduced to enhance conciseness.

Finally, a clearer reference to the international context has been included to strengthen the applicability of the findings.

Thank you once again for your valuable review.

Reviewer 2 Report

Comments and Suggestions for Authors

This study presents a descriptive, cross-sectional analysis of self-perceived health, mood, sleep, substance use, dietary habits, and leisure activities among 120 adolescents (aged 14–17) attending a public secondary school near Barcelona. The authors identify gender-based differences in mood, sleep patterns, physical activity, and substance use, emphasizing the need for gender-sensitive public health strategies and school-based interventions to promote adolescent well-being.

The study addresses highly relevant and timely public health issues related to adolescent behavior and health disparities, with a specific focus on gender differences. It provides a comprehensive overview of several interrelated health factors, including emotional well-being, lifestyle behaviors, and socio-demographics. The adoption of items from recognized tools such as the MFQ, PSQI, and ESPAD enhances the credibility of the findings. The manuscript offers valuable insights for local policymakers and school-based health promotion initiatives.

The innovative aspects of the study can be summarized in the analysis of gender differences. The finding that girls report higher levels of substance use (alcohol, tobacco, marijuana) than boys contrasts with much of the previous literature and indicates emerging changes in risk profiles that require updated prevention strategies.

The study takes a holistic perspective, analyzing variables of mental health, physical health, and risk behaviors. This perspective allows the authors to identify patterns and intersections between behaviors often studied separately.

Furthermore, the study frames self-perceived health and mood not only as outcomes, but as predictors or indicators of broader health behaviors, an approach in line with recent developments in adolescent health research, but still underused.

Finally, the manuscript does not limit itself to analysis, but moves towards concrete recommendations for local policy makers, suggesting gender-sensitive school interventions, bridging the gap between research and practice.

From this perspective, the study contributes new insights into gendered patterns of substance use that challenge assumptions and provides a multidimensional framework that could inform personalized and location-based prevention interventions.

The manuscript is very interesting and I have identified some areas of improvement that could strengthen it. Below are some questions for the authors that I hope will help them improve this very interesting manuscript.

Methodology

1. Could the authors explain the rationale for choosing a single public school as the study site?
2. The authors constructed a questionnaire, adapting existing instruments (130-142)
   Self-perceived health: was it created for administration in this study? For the adaptations of the MFQ, PSQI, and ESPAD the authors Could the authors clarify whether the instruments used were tested for internal consistency (e.g., Cronbach’s alpha) in their sample? If the length of the manuscript allows, could they share the internal consistency results?
   Could the authors explain which validated nutritional behavior questionnaire they used for Dietary habits?
   Finally, which instruments they used for Analysis of digital technology use and participation in physical activities.
3. Given the cross-sectional nature of the study, how do the authors plan to address potential limitations in drawing causal inferences from the observed associations?

Results

1. Did the authors consider including a single summary table that combines all significant gender-based findings to facilitate comparison?

Discussion and conclusion

1. The sampling strategy should be better contextualized and the limits of generalizability should be stated more explicitly as well as the reasons behind the sample size. Could the authors add some informations?
2. Could the authors further explore sociocultural factors to explain the finding that girls reported higher substance use than boys?
3. Can the authors further explain the relationship between sleep duration and digital technology use? How might screen time mediate sleep patterns in the study population?
4. In their conclusions, the authors highlight the need for action at the municipal level. Could the authors indicate whether specific programs exist in the study site? Or could they suggest specific interventions that schools or local health services could implement?
5. Could the authors add the limitations of this study?
6. Could the authors suggest future directions for research in this area?

Comments on the Quality of English Language

Small adjustments:

1. I have noticed occasional repetitions and would suggest standardizing "girls/boys" or "females/males".
2. In the abstract, I suggest to substitute "examinate" with "examine".
3. In the introduction, I would reword the sentence "Public health plays a crucial role in promoting the well-being of adolescents by developing health education programs..." (lines 72-73) to make it clearer to read. In the Discussion (line 297), "recommendations" are mentioned, I would insert the exact citations and link them more explicitly to the results.

Author Response

We sincerely thank the reviewer for their thorough reading of the manuscript and for their valuable comments, which have undoubtedly contributed to improving the overall clarity and quality of the study. Below, we address each of the observations raised point by point.

We believe that the results obtained provide a useful and complementary tool to the Local Health Indicators Reports, as they help guide, design, and evaluate more effective municipal policies in the areas of health promotion and education. From a political and territorial perspective, it is important to emphasize that not all municipalities share the same realities or behavioral patterns among boys and girls. In this regard, the data presented in this study offer added value by allowing for a more precise assessment of local needs and specificities. This, in turn, facilitates the design of more tailored strategies adapted to each context, with special attention to gender inequalities and sociocultural factors influencing adolescent health.

Methodology The study was conducted in the only public secondary school in the municipality, which naturally determined the selection of the study site. This decision was also based on operational feasibility and the strong collaboration between the school’s leadership team and the municipal health services, which ensured a high participation rate and a rigorous data collection process in a supportive and accessible environment committed to improving adolescent well-being.

The questionnaire used in this study includes adapted versions of well-established instruments, such as the MFQ, PSQI, and ESPAD, all validated for use with Spanish-speaking adolescent populations. Additionally, a specific item was developed to assess self-perceived health, based on formulations used in national-level studies. It is important to highlight that this survey is part of a broader initiative that has been implemented in over 100 municipalities across Catalonia, involving more than 23,000 students. This trajectory supports the validity and reliability of the instrument and positions it as a representative and robust tool for analyzing adolescent health and lifestyle behaviors. In our study, the structure and core items of the original questionnaire were maintained, ensuring methodological consistency and enabling comparisons with other local and regional contexts.

To assess eating habits, we used adapted items from the EnKid questionnaire and the HBSC study, both widely used references in public health for adolescent populations. Regarding digital technology use and physical activity, we included ad hoc items inspired by previous studies from the Spanish Ministry of Health and the HBSC survey, aiming to capture current behaviors related to screen time, social media, and physical activity in educational settings.

We acknowledge the limitations inherent to the cross-sectional design of the study, particularly the inability to infer causal relationships between variables. Nevertheless, the findings allow for the identification of relevant patterns and trends that may inform future longitudinal research and the development of targeted interventions based on the identified needs.

Some of these elements have been incorporated into the revised manuscript.

Results – Summary Table by Gender We appreciate the suggestion. Although we find the proposal valuable, an additional summary table was not included due to the journal’s limitations on the number of tables. However, we believe that gender-based findings are clearly and sufficiently presented in the existing tables, allowing readers to make comprehensive and accurate comparisons of the most relevant results.

Discussion and Conclusions We appreciate the reviewer’s insights. As indicated in the manuscript, the study was conducted in the only public secondary school in the municipality, which affects both the sample size and the generalizability of the results. However, this context allows for a highly accurate representation of the local reality, which is crucial for designing public health strategies that are responsive to the specific needs of the territory.

With regard to the findings—particularly the higher substance use reported among girls and the influence of screen time on sleep—we recognize the relevance of sociocultural factors that warrant deeper exploration. For this reason, a second, qualitative phase has been planned as a follow-up to this study, which will allow us to explore these issues further from the adolescents’ own perspectives.

After analyzing the results, they were presented to the local City Council with the aim of developing and implementing health promotion actions tailored to the identified needs. These include gender-sensitive school- and community-based interventions focused on emotional well-being, healthy technology use, and substance use prevention.

Finally, the main limitations of the study have been acknowledged and are now clearly reflected in the manuscript.

Language and Style
We appreciate the reviewer’s careful reading and valuable suggestions regarding language and consistency. The occasional repetitions have been addressed, and terminology has been standardized by consistently using either “girls/boys” or “female/male adolescents,” depending on the context and level of formality. In the abstract, “examinate” has been corrected to “examine.”
In the introduction, the sentence regarding the role of public health in promoting adolescent well-being has been reworded for improved clarity and readability.

We remain at your disposal for any further modifications that the reviewer or editorial board may deem appropriate.
Kind regards, and thank you once again for the thorough and constructive review.