There are many clinical indicators for detecting anemia in children, among which the more commonly used ones include hemoglobin, mean red blood cell volume (MCV), mean red blood cell hemoglobin content (MCH), etc.: 1. Hemoglobin: the most commonly used clinically is the level of hemoglobin, and the level of hemoglobin for determining anemia varies in different age groups. If the hemoglobin level is <145g/L for newborns, <90g/L for 1-3 months, <100g/L for 4-6 months, <110g/L for children 6 months to 6 years old, and <120g/L for children 6-14 years old, they are all considered anemic. The degree of anemia in children is usually clinically classified into four degrees. The first one is if the hemoglobin value is lower than the normal value for that age group but >90g/L, it is called mild anemia, if the hemoglobin value of children is 60-90g/L it belongs to moderate anemia, if it is below 60g/L it belongs to severe anemia; 2. MCV, MCH: MCV refers to the average red blood cell volume and MCH refers to the average red blood cell hemoglobin value, these two values can also be used to These two values can also be used to determine the type of anemia. For example, if MCV decreases and MCH is also small, it belongs to microcytic anemia. If the MCV increases and the MCH is also large, it is a large cell anemia.