Metal development index(MDI)and the psychomotor development index(PDI) comparatively divergence marked (P<0. 01).
智力发育指数和运动发育指数比较，差异显著（P<0．01）。
2
The infants MDI differed in the type of family and had obvious discrepancy (P<0.05), but the PDI had no significant discrepancy.
家庭类型不同的婴幼儿之间MDI差异有统计学意义（P<0.05），而PDI差异无统计学意义。
3
The mental development index (MDI) and the psychomotive development index (PDI) at 18 months in the intervention group were much higher than those of the control group (P <0. 001 ).