What are the I-IV blood type descriptions shown below (commonly used in Eastern Europe), and how do you translate them into the ABO-system?

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    $\begingroup$ What do you mean by translate? $\endgroup$ – WYSIWYG Nov 11 '14 at 7:09
  • $\begingroup$ @WYSIWYG: Convert it to the system used in the West: redcrossblood.org/learn-about-blood/blood-types $\endgroup$ – MikeF Nov 11 '14 at 7:14
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    $\begingroup$ I still don't understand. Isn't it already clear from the image? $\endgroup$ – WYSIWYG Nov 11 '14 at 7:15
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    $\begingroup$ @WYSIWYG: What's this (I), (II), (III), etc. stuff? I guess that's what I'm asking. $\endgroup$ – MikeF Nov 11 '14 at 7:17
  • $\begingroup$ I think this description is wrong. Blood type used to be described as AB-I, A-II, B-III and O-IV plus Rh Positive or Negative. $\endgroup$ – antonio Feb 13 '19 at 23:59

It is a direct correlation between the ABO blood groups and the Roman numerals.

 O: I

 A: II



This numeric system was pioneered by Jan Jansky of Czechoslovakia in the early 20th century. Apparently it is still used in some former Soviet states.

Erb IH. 1940. Blood Group Classification (A Plea for Uniformity). Can Med Assoc J 42(5):418-421.

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    $\begingroup$ I can't upvote it (not enough rep.) But thanks for the info! $\endgroup$ – MikeF Nov 11 '14 at 7:45
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    $\begingroup$ @MikeF you should be able to accept it by clicking the check mark. $\endgroup$ – canadianer Nov 11 '14 at 8:01
  • $\begingroup$ What would O+ in the US be in the UK? $\endgroup$ – user5434678 May 21 '16 at 7:13

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