Fig. 2

Qualitative synthesis of effects of prematurity/low birthweight on measures of cognitive function. Numbers indicate studies that found measures of cognitive function to be affected in both sexes, to be affected more in females, to be affected more in males, or to be affected in neither sex in childhood (1–10 years), adolescence (11–18 years), and adulthood (over 19 years). In each age group, the y-axis indicates the logarithm (base 10) of the sample size. A single study could show different results for different traits and so may appear in more than one cell. Study numbering is the same as in text. Circles indicate studies that examined sex-dependence using statistical interaction terms, whereas squares indicate studies that analyzed the sexes separately