China
Descriptive (Case report/series)
Medical records
1775
Patients infected with SARS-CoV-2 in Wuhan Jinyintan Hospital. Controls (Wuhan Area) N=3694
none
0
COVID-19 (any condition)
Patient characteristics
ABO blood group
Persons with other than 0 blood group
1317
3761
0 blood group
458
1708
Odds ratio
0.680 (0.600-0.770)
Yes
No
random effects model
Average