Red Cell Distribution Width (RDW) is a crucial component of a complete blood count (CBC) test. RDW helps guide the practitioner in dealing with some types of anemia. Anemia affects the global population by 27%. Understanding RDW results provides valuable insights for patients and practitioners, potentially identifying underlying health issues and guiding appropriate medical consultations. The purpose of the article is to investigate this individual marker in depth, help guide the ... RDW (red cell distribution width) tests measure the variation in red blood cell size, helping diagnose anemia and other blood disorders. An RDW (red cell distribution width) test measures the size and volume of your red blood cells. High results can be a sign of various conditions. Red cell distribution width (RDW) test identifies the sum of red blood cell variation in volume and size. Get the meaning behind a low or high test result and more.