Question

A study was performed looking at the risk of fractures in three rural lowa communities according to whether their drinking water was "higher calcium," "higher fluorides," or "control" as determined by water samples. Table 1 presents data comparing the rate of fractures (over 5 years) between the higher-calcium vs. the control communities for women ages 20-35 and 55-80, respectively 1 What test can be used to compare the fracture rates in these two communities while controlling for age? 2 Implement the test in Problem 1, and report a p-value (two-sided). A study was performed looking at the risk of fractures in three rural lowa communities according to whether their drinking water was "higher calcium," "higher fluorides," or "control" as determined by water samples. Table 1 presents data comparing the rate of fractures (over 5 years) between the higher-calcium vs. the control communities for women ages 20-35 and 55-80, respectively 1 What test can be used to compare the fracture rates in these two communities while controlling for age? 2 Implement the test in Problem 1, and report a p-value (two-sided) 3 Estimate the OR relating higher calcium and frac- tures while controlling for age. 4 Provide a 95% CI for the estimate obtained in Prob- lem 3 TABLE 1 Relationship of calcium content of drinking water to the rate of fractures in rural lowa Number of women Total number of women Total number Ages 20-35 Ages 55-80 Number of women with fractures with fractures of wamen 3 Control 37 Control 11 121 Higher calcium 33 Higher calcium 21 148

Answer 1

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