Inter-relationships of depression and anxiety symptoms among widowed and non-widowed older adults: findings from the Chinese Longitudinal Healthy Longevity Survey based on network analysis and propensity score matching - Li, Yinglin; Lin, Doudou; Gong, Xuan; Fu, Dou; Zhao, Ling; Chen, Weibing; Chen, Jie; Liu, Shanshan; Yang, Guirong; Cai, Zhongxiang (Frontiers in Public Health, 2025)