Use the following information to answer questions 4-8. suppose that 50,000 women who have never had a breast cancer diagnosis are available and willing to participate in a new screening program of computerized digital mammography. 1132 women had a positive screening test. all of these positive women had a breast biopsy and 136 were diagnosed with breast cancer. of the 48,868 who screened "negative" on the test, 24 were in fact in the detectable pre-clinical phase. this was determined by following these women and observing that all 24 were diagnosed with breast cancer within one year of the screening test.

a colleague in another city reports that the same screening test (with the same sensitivity and specificity) is achieving a predictive value positive of only 6%. what is the explanation for this?

a.
the colleague is screening a higher risk population

b.
the colleague is screening a lower risk population

c.
the colleague is screening a larger population