这项调查是由美国波士顿布莱根妇女医院劳雷尔“叶慈博士完成的，1981——1984年叶慈博士对七十岁出头的人进行了调查，此后对他们的调查每年进行一次直到2006年。

The survey, carried out by Dr Laurel Yates, of Brigham & Women's Hospital, in Boston, questioned the men between 1981 and 1984 when they were in their early 70s, and then annually until 2006.

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