The working principle of children's intelligence tester is mainly to infer the intelligence level of the tested children through IQ testing methods such as PPVT, WISC, CRT and MOD.

(1) The principle of intelligence test is determined by testing IQ, which means IQ is a quantitative unit to measure individual intelligence level.

In order to have a quantitative evaluation of people's intelligence level, psychologists invented intelligence tests, worked out a number of test questions through spot checks and investigations, and worked out the norm of a certain area, so that each level of test questions represented a certain age level, and then calculated IQ according to the formula.

1. Children's Picture Vocabulary Test (PPVT) Each picture represents a vocabulary. Its principle is to test children's intelligence level through auditory vocabulary (language).

2. Children's Combined Raven Test (CRT) is a non-verbal intelligence test created by British psychologist J.C. Raven. Since 1980s, combined with the specific situation in China, professionals from health, education, scientific research and other departments have developed the China revised edition, with 6 groups of 72 pictures.

3. After revision in China, MOD is classified as 17 scoring standard. The conclusion of the study is the correlation coefficient between the painter's IQ and that obtained by Webster and Stanford Binet.Alfred. Alfred scales is 0.55~0.08, which is closely related.

4. Height and weight test (body mass index), boy: (father height+mother height) × 0.54; Girl: (father's height ×0.932+ mother's height) ÷2. This formula is an international general formula, and the specific height is related to later nutrition and exercise.