All the boys were participating in a more substantial longitudinal study. Infant head measurements are typically done regularly by pediatricians through the initial 1. 5 years of life, but aren’t reliably done after that. Head circumference is calculated from the brow, or ridge above the optical eyes, around to the bony bump on the trunk of the skull and back again around to the brow. Three measurements, including at birth, were required to chart the growth of each young child and review it with the number of normal development. Webb said generally parents would have a difficult time detecting abnormal development because there is a range of normal head sizes. Approximately 20 % of children with autism have abnormally large head sizes, or what is called macrocephaly.The study process was accepted by the relevant ethics committee for every participating site. All subjects gave written informed consent. The study was designed by the executive steering committee , in cooperation with the sponsor . Data were collected, maintained, and analyzed by the sponsor, with the assistance of MDS Pharma oversight and Services by the executive steering committee. The scholarly study was monitored by an unbiased data and safety monitoring committee.