Suppose the expected number of breast cancer cases among a large number of 45- to 49-year-old women in this study who were followed for 7 years is 149, while the observed number of cases is 107. Are there an unusually small number of cases among Asian women? Why or why not?

Cancer

The Shanghai Women’s Health Study (SWHS) was undertaken to determine risk factor for different cancers among Asian women. The women were recruited from urban communities in 1997−2000 and were interviewed every 2 years to obtain health-related information.

One issue is whether risk prediction models derived from American populations are also applicable to Asian women.