Multi-professional primary care practices (Maisons de Santé Pluriprofessionnelles, MSP) have expanded widely in France over the last decade to respond to increasing healthcare needs, uneven distribution of physicians, and deteriorating working conditions, which were further exacerbated by the COVID-19 pandemic. MSPs are expected to offer more collaborative and coordinated care, and to provide a more attractive work environment, particularly for younger healthcare professionals seeking less isolation and better work-life balance.

Well-being at work for healthcare professionals is now recognised as a key determinant of quality and safety of care. Studies have shown links between staff satisfaction, burnout, and patient outcomes, including communication quality, error rates and staff retention. However, research specifically focused on collective well-being or "shared happiness" within multi-professional primary care teams remains limited. Existing work in French MSPs (notably qualitative studies by F. Burté and O. Caillaud) has identified relevant dimensions of "shared happiness" and led to the preliminary construction of a questionnaire named the Shared Happiness Index (Indice de Bonheur Partagé, IBP). To date, no validated, standardised instrument exists to measure this collective well-being in MSPs.

The Be_aPi study aims to validate the IBP questionnaire among healthcare professionals working in MSPs. The study is observational, descriptive and cross-sectional, conducted in several French regions covered by the GIRCI (Groupement Interrégional de Recherche Clinique et Innovation) SOHO (Sud-Ouest Outre-Mer Hospitalier) network (Nouvelle-Aquitaine, Occitanie, Réunion and Mayotte). It comprises three main steps. First, a content validation phase will be carried out with two independent panels of experts. One panel, including psychometrics, methodology and linguistics experts and MSP representatives, will assess face validity by examining each item in relation to the concept of shared happiness in multi-professional primary care. A second panel will be involved in an e-Delphi process to establish consensus validity on the relevance and clarity of items, using Likert-type ratings and iterative feedback.

Second, the psychometric validation phase will recruit approximately 350 professionals from over 100 MSPs. Eligible participants include medical and paramedical professionals, medical-social staff, medical assistants, coordinators, health mediators, adapted physical activity instructors and psychologists, working in MSPs that have been operating for at least one year, with at least one year of seniority in their current MSP. Participants will complete an online survey including the IBP questionnaire and three reference instruments: the Maslach Burnout Inventory (MBI), the General Health Questionnaire-12 (GHQ-12) and the Short Form-12 (SF-12). Internal consistency of the IBP will be assessed using Cronbach's alpha, and construct validity will be examined with exploratory factor analysis and correlation patterns with the reference scales, according to a multi-trait multi-method approach.

Third, to evaluate test-retest reliability, participants who completed the initial IBP will be invited to fill in the same questionnaire again after a delay of approximately one month. The stability of scores over time will be assessed using intraclass correlation coefficients. Ceiling and floor effects, as well as the distribution of scores across professional categories and organisational characteristics of MSPs (e.g. single-site vs multi-site, role in the organisation, membership in interprofessional associations), will also be analysed.

The expected outcome of Be_aPi is a valid, reliable and transferable Shared Happiness Index specifically tailored to multi-professional primary care practices. This tool should enable regular monitoring of collective well-being, support targeted quality-of-work-life interventions, and ultimately contribute to improving quality and safety of care, staff retention and the long-term sustainability of MSPs. In the longer term, the IBP could inform policy instruments and financing schemes that aim to "take care of those who care," in line with national quality and safety strategies.

Inclusion Criteria:

• Healthcare professionals (medical, paramedical) and professionals in the medical-social sector, medical assistants, health coordinators and mediators, as well as adapted physical activity instructors and psychologists
• who work in healthcare centres that had been operating for more than one year at the start of the study and who themselves had more than one year's seniority in the MSP.

Exclusion Criteria:

• Substitute professionals,
• Secretaries without coordination or medical assistant duties Professionals belonging to MSPs that had been operating for less than one year at the start of the study and who had less than one year's seniority within the organisation.

healthcare professionals