Diagnosis of Polycythemia Vera Complete blood count (CBC) Testing for JAK2, CALR, or LNK mutations (done sequentially) Sometimes RBC mass determination, if available Polycythemia vera is often first suspected because of an abnormal CBC (eg, hemoglobin > 16.5 g / dL [> 165 g / L] in men or > 16.0 g / dL [> 160 g / L] in women).