Key points are not available for this paper at this time.
R. Shepherd Zeldin, Stephen A. Small, Ritch C. Savin-Williams, Prosocial Interactions in Two Mixed-Sex Adolescent Groups, Child Development, Vol. 53, No. 6, Early Adolescence (Dec., 1982), pp. 1492-1498
Zeldin et al. (Wed,) studied this question.