The changing yardstick in measurement of cognitive abilities in infancy.

There are concerns regarding accurate measurement of cognitive function in infants, particularly those at biologic risk. Herein we discuss these issues and make recommendations. Concerns include: 1) secular changes in test norms, referred to as the Flynn effect; 2) changes in the content of revised test versions; 3) recent findings of higher mean scores in newer test versions when compared to previous scores; and 4) correction for prematurity. Caution is necessary when comparing the same test scores over extended periods of time, and using different versions of the same test when mean scores of the tests vary or evaluate different areas of functioning. Ideal solutions are not readily apparent and thus we provide several suggestions: control groups are essential for longitudinal studies; clinicians should not rely totally on cognitive scores; and further investigation of the Flynn effect in different subgroups of children at different ages is necessary.