Question

Current data provided by the 2010 census indicates that the prevalence of breast cancer in the US is still on the rise, while the mortality rates have slightly declined over time. A researcher at a local health department conducts an observational study to determine the prevalence in the particular region. The researcher gathers 2,168 participants and confirms 246 cases of breast cancer in her sample. The census data indicates a national prevalence of 23.5%. Do you feel that the breast cancer prevalence is more in the region of investigation compared to the national figure? Justify your answer with statistical reasoning.

Answer 1

We have to test whether the breast cancer prevalence is more in the region of investigation compared to the national figure

given that

sample proportion = 246/2168 = 0.113

sample size n = 2168

population proportion = 0.235

z test statistics =

using z distribution table for z value of -13.40, we get p value = 0.0000

So, at 0.05 significance level, result is significant as p value is less than significance level of 0.05. Rejecting the null hypothesis and concluding that the breast cancer prevalence is more in the region of investigation compared to the national figure