The role of multimorbidity and socio-economic characteristics as potential risk factors for Long Covid: evidence from the multilevel analysis of the Survey of Health, Ageing and Retirement in Europe's corona surveys (2020-2021)

多重疾病和社会经济特征作为新冠长期症状潜在风险因素的作用：来自欧洲健康、老龄化和退休调查新冠疫情调查（2020-2021 年）多层次分析的证据