Validation of NUTRENTO web app for teachers to assess healthy food environment practices in Mexican schools

Abstract In countries such as Mexico, where childhood obesity remains a pressing public health concern, schools are crucial environments for promoting healthy eating habits among children. Although national policies exist to improve school food environments, their implementation at the local level often lacks monitoring and support. Teachers are essential actors in translating these policies into everyday practices. However, validated tools for identifying and strengthening healthy food environments are lacking. The objective of this study was to develop and validate a progressive web application aimed at primary school teachers to identify the level of actions and elements that foster healthy school food environments in Mexico. A questionnaire based on ecosocial theory was developed and validated by expert judgment, covering seven dimensions related to healthy school food environments. A progressive web application (PWA) was developed, which included its own content management system (CMS). A total of 1462 teachers from 123 randomly selected schools completed the questionnaire using computers or mobile devices. Exploratory and confirmatory factor analysis (CFA) methods were employed to validate the scale. Results. From the CMS, 970 complete responses were retrieved for 52 content-validated items. In the EFA, there were six factors for 36 items, indicating excellent sampling adequacy (KMO> 0.8). CFA indicated excellent model fit (CFI = 0.95, TLI = 0.945, RMSEA = 0.045, SRMR = 0.059). Cronbach’s alpha values ranged from 0.80 to 0.95, confirming internal consistency. The app represents the first validated digital tool in Mexico with open access for any device. The PWA is a large-scale instrument that provides real-time data to identify teachers’ roles as mediators of the school food environment, helping prioritize and monitor interventions within schools. Competing Interest Statement The authors have declared no competing interest. Funding Statement Yes Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Not Applicable The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The project was approved by the Ethics and Research Committee of the Institute of Health Sciences of the Autonomous University of the State of Hidalgo (folio 200/2023), which is governed by the ethical principles for medical research on human subjects of the Declaration of Helsinki and the Mexican General Health Law. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Not Applicable I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Not Applicable I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Not Applicable Data Availability The data presented in this study are not publicly available due to privacy restrictions. Data are available on request from the corresponding author. Data Availability Statement The data presented in this study are not publicly available due to privacy restrictions. Data are available on request from the corresponding author.