This study examined the effects of training children?perceive ability, comparison ability, abstract and generalization ability on the development of 3-4 years olds?ability of classifying objects according to experimenter-named properties and ability of direct classification.

This study selected 4-year-old children, tried to explore the relationship between children\'s temperament and self-control.

Study on maternal consciousness of 3-year-old children s mothers between China and Japan;

A clinical analysis of mortality of children aged 0~4 years old in Heihe city from 2004 to 2006;