PhlebotomyBloodlettingHemochromatosisPolycythemiaIron OverloadAnemia, NeonatalPolycythemia VeraChelation TherapyFerritinsIronErythropoietinPorphyria Cutanea TardaHematocritBlood Specimen CollectionTime FactorsTreatment OutcomeCerebrospinal Fluid PressureBlood Volume DeterminationAnemiaErythropoiesisHemoglobinsRetrospective StudiesBlood Component TransfusionSensitivity and SpecificityProspective StudiesNitrilotriacetic AcidBlood TransfusionReproducibility of ResultsPhenylhydrazines