Since the study began in 1956, a grand total of 5676 adults have participated in the research! Approximately equal numbers of women (N=2977) and men (N=2696) have participated. In the most recent phase of the study occurring in 2008/10, there were 884 participants. In November 2011 the 10th wave of cognitive testing began. We anticipate testing will continue through December 2013.

The oldest participant in 2013 was 94 years old. The youngest participant in 2013 was 38 years old. Are there any “first timers” (those participating in 1956) remaining in the study? Yes! 13 “first timers” continue in the study. As might be expected, the “baby boomers” are well represented in the study with approximately 700 participants.

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