One historic source claimed that 25,000 subjects participated in the raising of the building's corner posts alone.
The subjects had participated in previous studies as preschoolers.
Researchers at Harvard, the ads said, were seeking subjects "to participate in a memory study."
In total 30 subjects participated in the studies spanning 10 sites in 4 countries.
In all, 100 subjects participated, generating 1,200 outcomes for groups and 3,000 for individuals.
Because many subjects participated in multiple examinations, we could conduct various longitudinal analyses.
A total of 151 gifted subjects participated in the study alongside 136 controls.
All 49 subjects participated in this study after giving written informed consent.
Approximately 4,500 subjects participate in the survey.
One of the difficulties encountered by the Birth to Twenty is that many subjects move out of the area, and can no longer participate.