Packed red blood cells do not have an antibody, since the greatest risk of Rh incompatible blood is to current or future pregnancies. For RBCs, type O negative blood is considered a "universal donor" as recipients with types A, B, or AB can almost always receive O negative blood safely. Type AB positive is considered a "universal recipient" because they can receive the other ABO/Rh types safely. These are not truly universal, as other red cell antigens can further complicate transfusions. There are many other human blood group systems and most of them are only rarely associated with transfusion problems. A screening test is
Jehovah's Witnesses and blood transfusions their comments into English reads: According to sociologist Richard Singelenbreg, the statement appearing in the Dutch edition of "Consolation" may have been published without knowledge of the doctrinal position published in the English July 1945 issue of "Consolation" by the Watch Tower Society's headquarters in the United States. In 1945, the application of the doctrine on blood was expanded to prohibit blood transfusions of whole blood, whether allogeneic or autologous. The prohibition did not specify any punitive measures for accepting a transfusion, but by January 1961—in what was later described as an application of "increased strictness"—it was ruled that it