Age effects in medical care. The type of medical care a patientreceives may vary
ID: 2918679 • Letter: A
Question
Age effects in medical care. The type of medical care a patientreceives may vary with the age of the patient. A large study ofwomen who had a breast lump investigated whether or not each womanreceived a mammogram and a biopsy when the lump was discovered.Here are some probabilities estimated by the study. The entries inthe table are the probabilities that both of two eventsoccur; for example, 0.321 is the probability that a patient isunder 65 years of age and the tests were done. The fourprobabilities in the table have sum 1 because the table lists allpossible outcomes.
Tests Done?
Yes No
Age under 65 0.321 0.124
Age 65 orover 0.365 0.190
(1) What is the probability that a patient in this study isunder 65? That a patient is 65 or over?
(2) What is the probability that the tests were done for apatient? That they were not done?
(3) Are the events A = (the patient was 65 or older)and B = (the tests were done) independent? Were the testsomitted on older patients more or less frequently than would be thecase if testing were independent of age?