This study aims to develop an Italian-language questionnaire assessing awareness, knowledge of infectious risk prevention strategies, and vaccination attitudes among splenectomized individuals. The questionnaire will be developed through a structured Delphi consensus process involving a multidisciplinary panel of healthcare professionals experienced in infection prevention and vaccination strategies. Two Delphi rounds will be conducted online to evaluate item relevance and clarity. Items reaching predefined consensus thresholds will be included in the final questionnaire. The resulting tool will support future studies assessing preventive care awareness and vaccination uptake among splenectomized patients.

Individuals without a functioning spleen face a lifelong increased risk of severe infections, particularly from encapsulated bacteria. Preventive strategies include vaccination, antibiotic prophylaxis, and patient education. However, adherence to preventive measures remains suboptimal, partly due to limited awareness and knowledge among patients.

This study aims to develop a validated Italian-language questionnaire to assess awareness, knowledge of preventive strategies, and attitudes toward vaccination among splenectomized individuals.

A modified Delphi consensus methodology will be used. A multidisciplinary panel of healthcare professionals involved in managing asplenic patients will be recruited. Following a preliminary literature scoping review, draft questionnaire items will be generated and submitted to two Delphi rounds conducted online.

Participants will rate each item for relevance and clarity using structured Likert scales. Items reaching predefined consensus thresholds will be retained and refined between rounds. The final questionnaire will consist only of items achieving expert consensus.

The study does not involve patients directly and poses minimal risk, as participation is voluntary and responses are anonymized.

Inclusion Criteria:

• Healthcare professionals working at Fondazione Policlinico Universitario A. Gemelli IRCCS
• Professional experience in vaccination or infection prevention
• Clinical involvement in care of patients with asplenia or related conditions
• Italian native language proficiency
• Provision of informed consent

Exclusion Criteria:

• Participation in the expert panel is restricted to individuals who meet all predefined inclusion criteria. Failure to satisfy any inclusion criterion automatically results in exclusion from the study population

The study population consists of a multidisciplinary panel of healthcare professionals, including physicians, nurses, and healthcare assistants working at Fondazione Policlinico Universitario A. Gemelli IRCCS, with clinical or academic experience in vaccination and infection prevention, particularly in the management of patients with asplenia. Participants are selected to ensure representation from different specialties involved in the care of asplenic patients and will participate in a Delphi consensus process aimed at developing a questionnaire on infectious risk prevention awareness and vaccination attitudes.