{"entity":{"id":"haematocrit","kind":"term","name":"Haematocrit","aka":[],"tldr":"The share of blood volume made up of red cells. Normal is roughly 40 to 50 percent; in polycythaemia vera treatment aims to keep it under 45 percent, because above that clots become much more likely.","summary":"Haematocrit is measured on every full blood count. In polycythaemia vera it is the number treatment is steered by: the CYTO-PV trial showed that a target below 45 percent, compared with 45 to 50 percent, cut cardiovascular deaths and major clots by about two thirds. Some experts use a lower target of 42 percent in women, whose normal range is lower.","asOf":"2026-09-16","wikipedia":"https://en.wikipedia.org/wiki/Hematocrit","links":[{"label":"Wikipedia","url":"https://en.wikipedia.org/wiki/Hematocrit"}],"tags":["polycythaemia-vera","mpn"],"related":[],"cancers":["polycythaemia-vera"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":["cyto-pv"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"notes":[],"category":"Clinic basics"},"route":"/terms/haematocrit/","neighbours":{"cancer":[{"id":"polycythaemia-vera","kind":"cancer","name":"Polycythaemia vera (PV)","route":"/cancers/polycythaemia-vera/"}],"trial":[{"id":"cyto-pv","kind":"trial","name":"CYTO-PV","route":"/trials/cyto-pv/"}]}}