Height must be measured accurately, otherwise it cannot be reliably evaluated and, in particular, the growth rate of the child between measurements cannot be correctly calculated. How to measure height in a standard way? Many people think it is easy to measure height, just use a ruler, but in fact, height measurement is very delicate and has certain requirements for measuring tools. Measure the length of the body (lying length) and the top – hip length can use a standard measuring bed, portable measuring board. Measure the height or sitting height can use height meter or fixed wall ruler or soft ruler. The soft ruler should be made of cloth with lacquer, and should not be made of pure plastic with large stretch. The measurement of height differs between children under 3 years of age and those over 3 years of age. children under 3 years of age, due to the difficulty of standing measurement, are measured in the prone position. A standard measuring bed or a portable measuring board is used. The child removes shoes, socks, and cap, wearing only a single pair of pants, and lies on his or her back on the midline of the measurement bed floor. An assistant holds the child’s head so that it touches the headboard, with the child facing upward and both ears on a horizontal line. The measurer is positioned on the right side of the child, holding both knees in the left hand, is both legs together close to the measuring bed, and the right hand moves the foot plate so that it touches the heels on both sides. When using a bed with scales on both sides, attention should be paid to the consistency of the readings on both sides. If you use a bed without a scaffold or a portable measuring board, you should pay attention to the bottom edge of the footboard and the measuring tape in close contact, so that the footboard is perpendicular to the latter. Read the numbers shown at the footboard. When measuring the height of children and adolescents over 3 years old, use a vertical height meter or a standing ruler fixed to the wall. Before measurement, remove shoes, socks and hat, wear only an undershirt and shorts, make the child’s back against the height meter column or wall, heels, hips and shoulders in contact with the column or wall, take an upright position, eyes forward, chest slightly raised, abdomen slightly retracted, arms naturally hanging down, fingers together, heels close together. The angular tips are separated by about 60 degrees, and several points between the heels, hips and shoulder blades touch the column at the same time. The measurer’s hand holds the measuring board so that it moves gently downward, taking care to measure with the eyes, to be at a level with the board. Let the bottom of the board read when it touches the cranial vertex exactly. Some parents ask why the height measurement at night is shorter than that in the morning. That is because the height change during the day is the highest in the morning and the lowest in the evening, generally a difference of 1~2 cm, due to the day’s activities and weight pressure, which makes the intervertebral disc thinner, the arch shallower, and the spinal curvature increased.