Longitudinal studies provide developmental science with invaluable information about how variables and the associations between variables change across time, but typically give limited attention to the length of time over which that change occurs. The present study re-analyzed data from previously published meta-analyses of longitudinal data…

Studied 21 mentally handicapped children of 20-45 months and their parents to determine patterns of child care and teaching interactions. Although children spent more time with mothers than with fathers, parents did not differ as groups on the proportion of time spent in concentrated interaction with the child. (RJC)