Agreement and Divergence in Illness Perceptions among Primary Care Patient–Caregiver Dyads with Diabetes-related Foot Ulcers

BACKGROUND: Illness perceptions shape how patients and caregivers understand and respond to chronic conditions, yet little is known about how they align in diabetes-related foot ulcer (DFU) management. This study examined agreement and divergence in illness perceptions, including causal beliefs, among primary care patient-caregiver dyads with DFUs, offering insights to inform communication, education, and family-centered care. METHODS: A cross-sectional study of 50 consecutively recruited patient-caregiver dyads who completed the Brief Illness Perception Questionnaire (BIPQ). Agreement was assessed using intraclass correlation coefficients (ICC), paired-sample t-tests, and distribution of agreement patterns. Open-ended responses on DFU causal beliefs were thematically analysed to identify convergence and divergence. RESULTS: Moderate agreement across domains (ICC 0.58-0.70) with significant differences only in Identity, where caregivers attributed more symptoms to DFU than patients (5.30 vs. 3.98, p = 0.004). The greatest disagreement was observed for Consequences (54%) and Identity (42%), reflecting divergent perceptions of illness impact and symptom burden. Both groups most often attributed DFUs to behavioural factors, with greater alignment on lifestyle-related than biomedical or psychosocial determinants. CONCLUSIONS: This first quantitative study of DFU illness perceptions in patient-caregiver dyads reveals both concordance and divergence in illness understanding. Incorporating dyadic perspectives into routine care may improve communication and strengthen family-centered collaborative care. Future interventions could test whether reconciling divergences in Identity and Consequence perceptions reduces caregiver strain and improves patient self-care.