Hall C A
JAMA. 1981 Mar 20;245(11):1144-6.
An increase in the mean corpuscular volume (MCV), while not diagnostic of vitamin B12 or folate deficiency, is a valuable, readily available screening test. I discuss six instances where an increased MCV was recorded months prior to diagnosis and could, if noted, have led to an earlier diagnosis.
平均红细胞体积（MCV）升高虽不能确诊维生素B12或叶酸缺乏，但却是一项有价值且易于获得的筛查测试。我讨论了六个病例，这些病例中MCV升高在诊断前数月就已记录，如果当时注意到这一点，本可更早做出诊断。
