Use of the Weaver curve in a child with microcephaly

Example of the use of the Weaver curve in a child with microcephaly. The child's OFC was 42 cm at age 12 months (<2 SD below the mean on the standardized OFC charts). The standard score was calculated to be −2.95. The mother's OFC was 51 cm (standard score: −2.81) and the father's OFC was 52 cm (standard score: −2.95). The average parental standard score was −2.88. The intercept (point A) of the lines from the standard scores falls within 2 standard deviations of the regression line (solid diagonal line). The child's head size is considered to be normal in relationship to that of the parents.