作者@article {Johnson2001637 ={约翰逊,Miriam J. and Ekstr{\"o}m, Magnus and Currow, David C.}, title = {Observational studies and {\textquotedblleft}the eye of the beholder{\textquotedblright}}, volume = {56}, number = {1}, elocation-id = {2001637}, year = {2020}, doi = {10.1183/13993003.01637-2020}, publisher = {European Respiratory Society}, issn = {0903-1936}, URL = {//www.qdcxjkg.com/content/56/1/2001637}, eprint = {//www.qdcxjkg.com/content/56/1/2001637.full.pdf}, journal = {European Respiratory Journal} }