This document provides guidance on evaluating a patient presenting with anemia. It recommends: 1. Calculating the reticulocyte index to determine if the cause is blood loss, red blood cell destruction, or impaired red blood cell production. 2. If production is impaired, check the mean corpuscular volume to identify microcytic, macrocytic, or normocytic anemia. 3. Order targeted labs depending on the mean corpuscular volume to identify causes like iron deficiency anemia, vitamin B12 or folate deficiency, or bone marrow disorders.