WITH 100% VERIFIED ANSWERS
\.Sensitivity and specificity of a screening test refer to its: - ANSWERS✔-validity
\.The degree of agreement among several trained experts refers to: - ANSWERS✔-inter-judge
reliability
\.A test that determines whether disease is actually present is a - ANSWERS✔-diagnostic test
\.A new antibody test detects serum antibodies against virus X (sensitivity 99%, specificity 90%).
When applied in a group of hospitalized patients diagnosed as having virus X infections, the test
is found to have a positive predictive value of 85%. When used to screen a group of healthy
blood donors for virus X infections, the test is found to have a positive predictive value of 30%.
Which of the following best explains this difference between the positive predictive values? -
ANSWERS✔-The prevalence of virus X infection is higher among the hospital patients than
among blood donors
\.1. The conditions favorable to population screening for pre-symptomatic diagnosis
of a given disease include:
i. a relatively high prevalence of the disease.
ii. availability of effective treatment.
iii. a screening test with a high degree of sensitivity.
iv. availability of physicians to perform the screening test procedure.
, Which of the above statements are correct? - ANSWERS✔-i., ii., and iii. only
\.A person with an inapparent infection... - ANSWERS✔-can transmit the infection to others
\.The Centers for Disease Control and Prevention published an article concerning the high rate
of foot fungal disease in New Orleans. The article explains that there has been a high rate of
foot fungal disease in New Orleans for decades. Foot fungal disease in New Orleans is best
described as: - ANSWERS✔-endemic
\.The public health officer from Long Beach complains to you about the dreaded Pacific Pox. The
health officer says, "If people catch the Pox, they suddenly get the urge to dance in the sand and
fall dead on the beach within the hour." There are no survivors to interview so you deduce: -
ANSWERS✔-the case fatality rate of the Pox must be high
\.What factors comprise the epidemiologic triangle? - ANSWERS✔-agent, host, environmental
(all of the above)
\.Someone suggests immunization as a means of reducing disease, specifically the feared UJ
(uderlinger jacamoodi). What part of the disease cycle is he or she trying to affect? -
ANSWERS✔-host
\.With respect to a hypothetical rabies investigation conducted among veterinary workers (Dr.
Spot, 2003), researchers found that rabies was almost always fatal. This finding refers to: -
ANSWERS✔-virulence
\.the site where a disease agent enters the body is the: - ANSWERS✔-portal of entry
\.One must use care in interpreting occupational differences in morbidity and mortality
because: - ANSWERS✔-good health status may be a factor for selection into a job