Birth Order and Spacing

While much of the research on birth order is considered useful, many psychologists are quick to point out that it lacks strong scientific merit. One social psychologist has even likened birth order theory to astrology because of its rather liberal and far-reaching implementation. Another mentions that it is often a way for people to deny responsibility for their behavior. Judith Blake, author of Family Size and Achievement (1989), believes the size of the family into which a child is born is more important than the order of births in the family. She argues that the fewer the siblings there are, the more attention each child gets from the parents. And the more attention the child receives, the greater the chances of achievement in school verbal and behavioral skills are used more often through interaction with parents.

Probably the biggest setback to birth order research came from the writings of two Swiss psychologists, Cecile Ernst and Jules Angst. In a noteworthy 1983 critique of over a thousand studies on birth order, Ernst and Angst openly criticized the method by which many of these studies were conducted. Background variables, they argued, were inadequately controlled within the research, thereby rendering much of the significance of birth order useless. They further argued that the differences between families and number of siblings might be the cause for particular trends. A similar critique by Carmi Schooler in the early 1970s also called into question the validity of much of the birth order literature, citing most often poor research design as the culprit in the misrepresentation of the effects of birth order.