5.2.1  Length

A wooden measuring board (also called sliding board) is used for measuring the length of children under two years old to the nearest millimetre (as shown in Figure 5.1). Measuring the child lying down always gives readings greater than the child’s actual height by 1-2 cm.


To measure the length of a child under two years, you need one assistant and a sliding board.

As you can see in Figure 5.1, you need an assistant to help you measure a child using this method.

  1. Both assistant and measurer are on their knees (arrows 2 and 3).
  2. The assistant holds the child’s head with both hands and makes sure that the head touches the base of the board (arrow 4).
  3. The assistant’s arms should be comfortably straight (arrow 5).
  4. The line of sight of the child should be perpendicular to the base of the board (looking straight upwards) (arrow 6).
  5. The child should lie flat on the board (arrow 7).
  6. The measurer should place their hands on the child’s knees or shins (arrow 8).
  7. The child’s foot should be flat against the footpiece (arrow 9).
  8. Read the length from the tape attached to the board.
  9. Record the measurement on the questionnaire (arrow 1).
Measuring child’s length
Figure 5.1  Measuring length. (Source: UNICEF, 1986, How to weigh and measure children: assessing the nutrition status of young children)

5.2  Anthropometric measurements used to assess growth

5.2.2  Height