https://www.selleckchem.com/products/Vorinostat-saha.html Previous literature has shown that chronic diseases and psychological distress are correlated. However, the mediating and moderating mechanisms underlying this relationship have not been sufficiently studied. The purpose of this study was to explore the role played by activities of daily living (ADL) and perceived social support. Face-to-face questionnaire-based surveys were conducted with 3250 valid participants (age ≥60 years). Participants were assessed using the Barthel Index, Perceived Social Support Scale, and Depression Anxiety Stress Scale-21. 1) Chronic diseases had a significant direct effect on psychological distress in older adults; 2) the relationship between chronic diseases and psychological distress was partially mediated by ADL; and 3) the impact of chronic diseases on psychological distress was significantly moderated by perceived social support. More importantly, perceived social support was a protective factor that could effectively alleviate the adverse effects of chronic diseases on psychological distress. The results add to the existing literature by uncovering the underlying mechanisms between chronic diseases and mental health. These findings have implications for early intervention and prevention of mental health problems in older adults. The results add to the existing literature by uncovering the underlying mechanisms between chronic diseases and mental health. These findings have implications for early intervention and prevention of mental health problems in older adults. Ensuring that future physicians are competent to practice medicine is necessary for high quality patient care and safety. The shift toward competency-based education has placed renewed emphasis on direct observation via workplace-based assessments in authentic patient care contexts. Despite this interest and multiple studies focused on improving direct observation, challenges regarding the objectivity of this ass