Great Smoky Mountains Study

The Great Smoky Mountains Study is a longitudinal study led by William Copeland (professor) from Duke University Medical Center that started in 1993 and ended in 2003. It followed 1,420 children from western North Carolina. Participants were interviewed at up to nine points in time - first aged 9 to 16, and again at ages 19–21.

During the study, about one quarter of the families saw a dramatic and unexpected increase in income. The study showed that among these children, instances of behavioral and emotional disorders decreased, and conscientiousness and agreeableness increased. Randall Akee remarked that "It would be almost impossible to replicate this kind of longitudinal study”.

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