Informal carers' perception on perspective taking when reporting as proxies about someone else's health.

PURPOSE: Informal carers ('proxies') are often asked to report on the health of individuals who cannot self-report, either from their own ('proxy-proxy') or the patient's ('proxy-person') perspectives. It remains unclear which perspective proxies find most useful. Understanding this is important for designing measures that proxies can complete. We conducted an exploratory study on which perspective proxies find most useful and why, when reporting pain and physical function in dementia and symptoms in multiple sclerosis (MS). METHODS: This study used data from two cross-sectional online surveys: one for proxies of people with MS and another for people with dementia. Proxies were asked to indicate which perspective they found most useful and why for communicating symptoms in MS, and pain or physical function in dementia, to healthcare professionals (HCPs). Quantitative responses were summarised using percentages; qualitative responses were analysed using content analysis. RESULTS: 55 proxies reported on MS symptoms, 29 on pain in dementia, and 33 on physical function in dementia. The most selected perspectives were: 35% (19/55) proxy-proxy for MS symptoms, 38% (11/29) proxy-person for pain and 39% (13/33) either of the perspectives for physical function. Proxy-person was valued for empathy and person-centredness, especially in reporting pain and MS symptoms. Proxy-proxy was appreciated for objectivity and reducing conflict, particularly in physical function. Using either perspective was considered most useful for balancing views and reducing misinterpretation in both conditions. CONCLUSION: Proxies' most useful perspectives vary slightly by domain and condition. Incorporating an understanding of how proxies approach the challenge of reporting may improve measure design.