In a case-control study with equal numbers of cases and controls, what is the number of women with a hip fracture who are not taking calcium supplements?

The given question was incomplete the complete question is as follows:

A history of dietary supplement with calcium was recorded among 10,000 women over the age of 50. The women were followed for 2 years to determine if they experienced hip fracture. Calcium supplementation was reported by 31% of women who experienced hip fracture and by 46% of all other women. In a case-control study with equal numbers of cases and controls, what is the number of women with a hip fracture who are not taking calcium supplements?

The correct answer would be - 3450.

Explanation:

In the case control study that is represent there is equal number of cases and control so the cases and controls would be 5000 in each type, which means there is 5000 cases and 5000 controls in this study.

Now for 5000 women who are cases, there would be 31 percent women who exposed to calcium supplement would be = 1550 women. This leaves the women with 69% or 5000 - 1550 = 3450 women.

Thus, the correct answer is - 3450.