The PROTHEE-QUALI study (Qualitative study of the lived experience of patients with prosthetic joint infection, their accompanying persons and health professionals and construction of a therapeutic education program for management: qualitative study) is categorized as non-interventional qualitative research.

In France, a prosthetic joint infection (PJI) is diagnosed in approximately 3000 patients per year. This complication is severe and results in major consequences for the patient, such as prolonged or repeated hospitalization, pain, anxiety, and a transient or permanent loss of autonomy, sometimes resulting in disability, or even amputation or joint resection. PJI management is complex, necessitating a multidisciplinary approach combining surgical treatment and prolonged antibiotic therapy (lasting from 6 to 12 weeks to several months).

The PROTHEE-QUALI project was designed to create this essential tool by collecting and crossing the perspectives of the affected patients, their accompanying persons, and the healthcare professionals involved.

The general objective of the project is the structuring of a TPE program destined for patients with PJI, aiming to improve their management and support. This includes assistance with adherence to and better tolerance of antibiotic treatments, pain management, physical rehabilitation, psycho-social care, providing information on the infection and its evolution, and adapting hygiene measures.

The primary objective is the exploration of the lived experience of patients with PJI, their accompanying persons, and the health professionals (nurses, physiotherapists, psychologists, and pharmacists) taking care of them in real-life settings.

The secondary objective is the structuring of a TPE program based on the crossed perspectives of patients, their accompanying persons, and health professionals concerning the issue of PJI.

PROTHEE-QUALI is an 18-month prospective multicenter qualitative study. It uses the IPSE qualitative research method ("Inductive process to analyze the structure of lived experience"). The design involves two main phases: Phase 1 focuses on exploring the experience through individual interviews (patients and accompanying persons) and focus groups (health professionals) to extract a structure of experience; Phase 2 involves the validation and elaboration of the TPE program proposal through feedback from new focus groups. The sampling technique used is non-probabilistic and intentional, known as "purposive sampling" with maximum variation, seeking exemplary situations and rich, diversified accounts rather than statistical representativeness.

Involved Structures The research is promoted by the Assistance Publique - Hôpitaux de Paris (AP-HP), with the Délégation à la Recherche Clinique et à l'Innovation (DRCI) ensuring the promoter's missions by delegation. The study is funded by a grant from GIRCI APRESO Convergence 2024.

The research is multicentric, involving three investigating centers which are Complex Osteoarticular Infection Reference Centers (CRIOACs) in the Île de France region:

• The CRIOAC of the Groupe Hospitalier Diaconesses Croix Saint-Simon.
• The CRIOAC Lariboisière Saint Louis.
• The CRIOAC Cochin. The qualitative and methodological team includes members of the INSERM U1153, Statistic and epidemiologic research center Sorbonne Paris Cité. The monitoring of the research is overseen by a Clinical Research Unit (URC).

PROTHEE-QUALI is a multicenter, non-interventional qualitative study (RIPH3) designed to explore the lived experience of prosthetic joint infection (PJI) and to use these experiential data to structure a Therapeutic Patient Education (TPE) program tailored to patient needs.

The study is grounded in the IPSE qualitative research method (Inductive Process to Analyze the Structure of Lived Experience), a rigorous phenomenological approach specifically developed for health research. IPSE aims to describe the invariant structure of a lived experience through an inductive, iterative analytic process combining individual and collective phases of analysis.

Data collection is conducted in two successive phases. Phase 1 focuses on accessing the structure of lived experience through individual semi-structured interviews with patients and accompanying persons, and focus groups with healthcare professionals. Phase 2 consists of validation and refinement of the proposed TPE program through new focus groups, using participant feedback on the Phase 1 results and preliminary educational framework.

Analysis follows the IPSE analytic sequence: independent descriptive analysis by several researchers, collective structuring of experiential categories into axes of experience, and triangulation with existing scientific and clinical knowledge to support the elaboration of the TPE program.

The study prioritizes depth of experience and maximum variation over statistical representativeness, in accordance with qualitative research standards.

Inclusion Criteria:

Patients :

• Age ≥ 18 years
• Have undergone surgery > 1 month and < 1 year ago for a hip, knee, or shoulder prosthetic implant, and are currently receiving or have received prolonged antibiotic therapy (≥ 6 weeks)
• Patients had to agree to sign a consent form to participate in the study.

Patient companions :

• Age ≥ 18 years
• Close relative or friend designated by the patient, who has accompanied them throughout their care journey, from diagnosis, during and after hospitalization, at least until the end of antibiotic treatment
• Not opposed to participating in the study

Healthcare professionals :

• Practicing for ≥ 1 year in a CRIOAC (Reference Center for Osteoarticular Infections)
• Role: nurse, physiotherapist, psychologist, pharmacist
• Not opposed to participating in the study

Exclusion Criteria:

Patients :

• Do not have proficiency in the French language
• Patients with advanced cognitive disorders
• Patients with severe depression

Patient companions :

• Do not have proficiency in the French language
• Patients with advanced cognitive disorders
• Patients with severe depression

Healthcare professionals :

-None

Patients managed in the CRIOAC unit, who underwent surgery for prosthetic joint infection more than one month and less than one year ago and were treated with antibiotic therapy.

Relatives or friends designated by the patient, who accompanied them throughout their care, from diagnosis, during and after hospitalisation, at least until the end of the antibiotic therapy.

Healthcare professionals (nurses, physiotherapist, psychologists, pharmacists) working for at least one year in the CRIOAC unit.