Multiple birth risk factors and the distribution of handedness.

In this study, we attempted to maximize the likelihood of replicating Bakan's (1971, 1977a) observations that left-handedness was more probable in college students who were the progeny of "high-risk" births. To do this, the relationships between handedness and a combination of factors known to be associated with birth risk were computed. The observed relationships proved to be trivial and thus the validity of Bakan's hypothesis was questionned.