title: The value of the serum vitamin B12 level in diagnosing B12 deficiency.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000437:Alcoholism / Q000097:blood; D000752:Anemia, Pernicious / Q000175:diagnosis; D003951:Diagnostic Errors; D005260:Female; D005492:Folic Acid / Q000097:blood; D006801:Humans; D007437:Intrinsic Factor / Q000032:analysis; D008286:Malabsorption Syndromes / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014805:Vitamin B 12 / Q000097:blood*; D014806:Vitamin B 12 Deficiency / Q000175:diagnosis*
chemical_list: D007437:Intrinsic Factor; D005492:Folic Acid; D014805:Vitamin B 12