Longitudinal analysis of development among single and nonsingle children in Nanjing, China: ten-year follow-up study.

In order to examine the impact of "one-child-per-couple" family planning policy on child development, a longitudinal study of a group of children in Nanjing, China, was carried out between 1984 and 1995. The same cohort of children was examined at four stages of development: preschool, early school, preadolescence, and adolescence. Achenbach's Child Behavior Checklist was used to measure the child's behavior. A total of 274 children were surveyed in all four stages. The total behavior problem scores obtained at different stages of development were compared among boys and girls. The results showed that the total score declined significantly in association with the time. As the child grew older, the problems score decreased significantly. This maturation effect was seen for both boys and girls. On average, boys' scores dropped from 21 to 11, whereas girls' scores went from 19.5 to 12. In comparing single with nonsingle boys, there were no significant differences throughout the four stages of development. However, girls who were single children, in contrast to girls with siblings, had significantly higher scores of total behavior problems at each stage of development. These findings illustrate that the longitudinal effect of being a "single-child" is similar to other studies, indicating a minimal impact of family policy. However, the effects were more prominent among girls. This phenomenon can be explained by parents' different attitude toward single-children because of gender difference.