2.With the age increasing,the time of nighttimesleep in regular time decreased gradually,being 9.28h,9.27h,9.04h,9.04h,8.96h and 8.85h in 6,7,8,9,10 and 11-year old children. But the time of nighttimesleep in these children at weekends was not significantly different.
3.The average time of nighttimesleep in 6~12 year-old children was (9.10±0.57)hours in regular time,and (9.47±0.81)hours at weekend( t =16.437, P =0.000).