Anemia-oriented history and physical examination, with particular emphasis on co-morbid conditions associated with anemia and drug history

CBC/diff/plt, absolute reticulocyte count, smear review

Tests of iron stores (Fe/TIBC, ferritin, soluble transferrin receptor)

Tests of B₁₂ deficiency; serum levels of cobalamin, methylmalonic acid, and serum homocysteine

Chemistry panel (using calculated creatinine clearance)

Serum erythropoietin (with caveat for what represents a “normal” erythropoeitin in an elderly person)

TSH, serum testosterone

Tests of inflammation ( e.g. ESR, C reactive protein)

Bone marrow aspiration and biopsy, cytogenetics (particularly if myelodysplastic syndrome is suspected)

RBC or serum folate level

Specialized tests of erythrocyte physiology (e.g., RBC mass determination, serum interleukin-6 determination)