Background: Performance-based tests (PBTs) objectively assess functional capacity and are increasingly applied in fibromyalgia (FM) to complement patient-reported outcomes (PROMs). However, evidence regarding their reliability, especially considering patients’ socio-occupational status, is limited. This study aimed to determine test–retest reliability of a standardized PBT battery in women with FM and to examine the influence of employment status on measurement stability. Methods: A total of 119 women were assessed (89 with FM). The battery included the 6 min walk test (6MWT), handgrip strength test (HST), and 8 feet up and go test (8FUGT). Test–retest reliability was examined using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and smallest real difference (SRD). Analyses were conducted for the total FM group and socio-occupational subgroups (actively working, claiming disability, and permanent disability). Results: All PBTs demonstrated excellent test–retest reliability. Measurement stability was consistently higher in controls. Absolute reliability indices confirmed acceptable measurement stability. However, the claiming disability group showed markedly higher SEM% and SRD% for HST, suggesting reduced reproducibility. The 6MWT and 8FUGT maintained excellent reliability and stability across all groups. PROMs showed good-to-excellent reliability. Conclusions: PBTs showed excellent reliability in women with FM. However, reliability varied across socio-occupational groups, particularly for HST in patients claiming disability. PROMSs showed lower reliability than PBTs.

Introduction Programmes for older people aimed at increasing physical activity (PA) and reducing sedentary behaviour (SB) traditionally focus on achieving functional and health improvements. Focusing on enjoyment and social inclusion could strengthen adherence and help reach older people with social disadvantages. The aim of this study is to assess the feasibility and acceptability of the Join4Joy approach in PA programmes and its assessment tools. Methods and analysis A multicentric, pragmatic, pre-post feasibility study using mixed methods will be conducted. The intervention will consist of a PA programme boosting enjoyment and social inclusion, grounded on a co-creation process. Trainers will offer twelve, 1-hour weekly sessions of structured, supervised, group-based PA. Participants will be encouraged to increase activity in daily living. 144 older people will be recruited from the community and nursing homes in Spain, Denmark, Italy, Germany, and France. Additionally, participants and trainers will be invited to join virtual communities of practice to share their experiences across settings and countries. Qualitative procedures will be used to explore the acceptability of the design via interviews and focus groups with participants and trainers. Quantitative methods will be used to assess uptake, adherence, retention, reach, satisfaction, enjoyment (PACES questionnaire), physical function (e.g., Short Physical Performance Battery), quality of life (EQ-5D-5L scale), perceived improvement (Patient Global Impression of Improvement scale-I), activities of daily living (Barthel index) and SB and PA patterns (IPAQ and accelerometry). The degree and type of participation in virtual communities of practice will also be assessed. SPSS software will be used for the analysis of quantitative variables. Qualitative data will be analysed using reflective thematic analysis following Braun and Clarke (2006). Ethics and dissemination A favourable report by the Research Ethics Committee of UVic-UCC (282/2023) was obtained on 26 June 26th, 2023. Participation and withdrawal will be voluntary. Participants’ (or their legal guardians’, when necessary) written permission will be required. Results of the study will be disseminated through publication of scientific articles, presentations at sport and health-related professional conferences and congresses, as well as through social media and via the Join4Joy website. Study registration ClinicalTrials.gov, NCT06100835.