Biological maturation and social development: A longitudinal study of some adjustment processes from mid-adolescence to adulthood.

The role of biological maturity in behaviors in adolescence which most often are considered as negative by adults was investigated for a normal group of girls. In mid-adolescence early matured girls were found to play truant, smoke hashish, get drunk, pilfer, ignore parents' prohibitions, considerably more often than did late maturing girls. These differences between biological age groups were mediated by the association with older peer groups and they leveled out in late adolescence. Data on alcohol consumption and crime at adult age showed little association with biological maturation. A hypothesis was tested suggesting that early biological maturation may have negative long-term consequences within the education domain. In accord with this assumption, a considerably smaller percentage of girls among the early maturers had a theoretical education above the obligatory nine-year compulsory schooling than among the late maturing girls. The association between biological maturation and adult education was significant also after controlling for standard predictors of education, such as the girls' intelligence and the social status of the home. The requirement of conducting longitudinal studies when investigating issues connected with maturation was strongly emphasized.