Diagnosis of the Disease

Since iron deficiency anemia is a from or anemia, it is key to define the medical diagnosis of anemia before introducing that of IDA. According to the World Health Organization anemia is classified with as a blood hemoglobin level of less than 7.7 mmo1/1 (13g/dl) in men and 7.4 mmo1/1(12g/dl) in women. IDA is a form of microcytic anemia, which is defined as having small, hypochromic blood cells and as a result is characterized by having small iron stores.

Clinical Diagnosis 

The clinical diagnosis of IDA occurs in individuals that have low hemoglobin (<7.7 mmo1/1 in men and <7.4 mmol1/1), a low serum iron (<7.1g/l), a low serum ferritin (storage from or iron) (<30ng/l), a low transferrin saturation (<15%), and I high total iron-binding capacity (>13.1 mol1/1)

Tests

CBC's
These individuals values are measured through several different blood tests called Complete Blood Cell tests or CBC's. These tests look at components in the blood such as:

• red blood cells (RBC's)
• white blood cells (WBC's)
• hemoglobin
• hematocrit
• platelets

Other tests  look at serum iron, serum ferritin, and transferrin level, which can be determined through CBC tests. 

Non-Blood Tests 
To test if individuals have internal bleeding doctors will conduct fecal occult to look for blood in the feces. Doctors may also suggest a pelvic ultra sound

picture: http://contemporarypediatrics.modernmedicine.com/contemporary-pediatrics/content/tags/american-academy-pediatrics/iron-deficiency-anemia-toddlers-tee 

http://www.nhlbi.nih.gov/health/health-topics/topics/ida/diagnosis

Johnson-Wimbley, T. D., & Graham, D. Y. (2011). Diagnosis and management of iron deficiency anemia in the 21st century. Therapeutic Advances in Gastroenterology, 4(3), 177–184. http://doi.org/10.1177/1756283X11398736