Which laboratory finding would most directly indicate anemia?

Which laboratory finding would most directly indicate anemia?

• A. Decreased hemoglobin
• B. Increased hematocrit
• C. Increased RBC count
• D. Normal platelets

Answer: (A)

Anemia is a state where the blood’s oxygen-carrying capacity is reduced, typically due to too little hemoglobin. The most direct signal of this is a decreased hemoglobin concentration, because hemoglobin is the protein in red blood cells responsible for carrying oxygen. If Hb falls, the blood’s ability to transport oxygen drops, regardless of how many red blood cells are present or how the plasma volume shifts. Hematocrit often parallels hemoglobin but can be affected by changes in plasma volume, making it a less direct measure of oxygen-carrying capacity. A higher red blood cell count would suggest the opposite of anemia, and normal platelets don’t provide information about red cell mass. So the decreased hemoglobin level is the clearest indicator of anemia.

Anemia is a state where the blood’s oxygen-carrying capacity is reduced, typically due to too little hemoglobin. The most direct signal of this is a decreased hemoglobin concentration, because hemoglobin is the protein in red blood cells responsible for carrying oxygen. If Hb falls, the blood’s ability to transport oxygen drops, regardless of how many red blood cells are present or how the plasma volume shifts. Hematocrit often parallels hemoglobin but can be affected by changes in plasma volume, making it a less direct measure of oxygen-carrying capacity. A higher red blood cell count would suggest the opposite of anemia, and normal platelets don’t provide information about red cell mass. So the decreased hemoglobin level is the clearest indicator of anemia.