Determinates of STI prevention service utilisation among young and hard-to-reach populations: a protocol for a mixed-methods study in Foggia district, Italy, 2025

Sexually transmitted infections (STIs) remain prevalent among young and hard-to-reach Italian populations. Several factors can be identified in this phenomenon despite prevention initiatives: there is little awareness among users of the different types of infection and how to prevent them; also, users often misunderstand how to use prevention and treatment services. This study aims to investigate determinants of STI prevention service utilisation among these population groups in Foggia district, Italy, incorporating healthcare worker and non-governmental organisation (NGO) and community association perspectives. This cross-sectional observational study employs mixed methodology conducted January-May 2025. The protocol comprises: (1) comprehensive service mapping; (2) three Knowledge, Attitudes and Practices surveys targeting 18-25 year olds, healthcare workers and NGO/community association representatives; (3) focus group discussions with target populations and (4) at least 24 in-depth interviews exploring communication practices. Quantitative analysis will utilise descriptive statistics and multivariate regression. Qualitative data will undergo inductive thematic analysis via Atlas.ti software through systematic transcription, coding and theme development. All procedures adhere to Good Clinical Practice standards and the Declaration of Helsinki with General Data Protection Regulation (GDPR) compliant data management protocols. The protocol was approved by the Ethics Committee of Foggia University Hospital on 17 December 2024.Results will be disseminated through scientific publications, conference presentations and stakeholder reports. Findings will inform the development of an evidence-based pilot model for STI prevention services in Foggia district.