3) Robinson, J.L., Mcgrath, J & Corley, R.P. (2001). The Conduct of the Study: Samples and Procedures. In R. Emde & J. Hewitt (Eds.), Infancy to Early Childhood: Genetic and Environmental Influences on Developmental Change (pp 23-41). Oxford University Press: New York, New York.

This chapter describes the recruitment, sample characteristics, zygosity determination, and assessments of twins at 14, 20, 24 & 36 months in the Macarthur Longitudinal Twin study. The study is a continuing enterprise and most of the families are still active participants. In this chapter, the types of data collection measures are presented and discussed in detail.