PUBH 6003 QUIZ 4 TEST BANK PRACTICE
QUESTIONS SOLUTIONS DETAILED
EXPLANATIONS VERIFIED
●● -Bias due to loss of subjects from the control group over time
Answer: In a case control study of the relationship between radiation
exposure and cancer, 50 cases admitted for thyroid cancer and 100
"controls" admitted during the same period for treatment of hernias were
studied. Only the cases were interviewed, and 20 of the cases were
found to have been exposed to x-ray therapy in the past, based on
medical interviews and medical records. The controls were not
interviewed, but a review of their hospital records when they were
admitted for hernia surgery revealed that only 2 controls had been
exposed to x-ray therapy in the past.
Based on the description given above, what source of bias is least likely
to be present in this study?
●● surveillance bias
Answer: It has been suggested that physicians may examine women who
use oral contraceptives more often or more thoroughly than woman who
do not. If so, and if this association is observed between phlebitis and
oral contraceptive use, the association may be due to:
, ●● individual matching, stratification, group matching, adjustment
Answer: Which of the following is an approach to handling
confounding?
●● -A necessary, but not sufficient, cause
-Neither necessary nor sufficient
Answer: . Factor A, B, or C can each individually cause a certain disease
without the other 2 factors, but only when followed by an exposure to
Factor X. Exposure to Factor X alone is not followed by the disease, but
the disease never occurs in the absence of the exposure to Factor X.
a. Factor X is....
b. Factor A is.....
●● predictive value
Answer: All of the following are important criteria when making causal
inferences except:
●● May be incorrect b/c mothers who had intercourse during the month
before childbirth may differ in other important characteristics from those
who did not
QUESTIONS SOLUTIONS DETAILED
EXPLANATIONS VERIFIED
●● -Bias due to loss of subjects from the control group over time
Answer: In a case control study of the relationship between radiation
exposure and cancer, 50 cases admitted for thyroid cancer and 100
"controls" admitted during the same period for treatment of hernias were
studied. Only the cases were interviewed, and 20 of the cases were
found to have been exposed to x-ray therapy in the past, based on
medical interviews and medical records. The controls were not
interviewed, but a review of their hospital records when they were
admitted for hernia surgery revealed that only 2 controls had been
exposed to x-ray therapy in the past.
Based on the description given above, what source of bias is least likely
to be present in this study?
●● surveillance bias
Answer: It has been suggested that physicians may examine women who
use oral contraceptives more often or more thoroughly than woman who
do not. If so, and if this association is observed between phlebitis and
oral contraceptive use, the association may be due to:
, ●● individual matching, stratification, group matching, adjustment
Answer: Which of the following is an approach to handling
confounding?
●● -A necessary, but not sufficient, cause
-Neither necessary nor sufficient
Answer: . Factor A, B, or C can each individually cause a certain disease
without the other 2 factors, but only when followed by an exposure to
Factor X. Exposure to Factor X alone is not followed by the disease, but
the disease never occurs in the absence of the exposure to Factor X.
a. Factor X is....
b. Factor A is.....
●● predictive value
Answer: All of the following are important criteria when making causal
inferences except:
●● May be incorrect b/c mothers who had intercourse during the month
before childbirth may differ in other important characteristics from those
who did not
