little c Ag:PrThr:Pt:RBC^Fetus:Ord
little c ag:prthr:pt:rbc^fetus:ord
c Antigen:Presence or Threshold:To identify measures at a point in time:Erythrocytes^Fetus:Ordinal
c antigen:presence or threshold:to identify measures at a point in time:erythrocytes^fetus:ordinal