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COMLEX II: Statistics Questions and
Verified Answers
How do you calculate relative risk?
Ans: [A/(A+B)]/[C/(C+D)]
expresses the risk of disease in people exposed to a given factor
What type of study uses relative risk to evaluate conclusions?
Ans: cohort study
what type of study uses odds ratio to evaluate conclusions?
Ans: case-control study
what is the difference between case-control and cohort studies?
Ans: cohort study: examines a group of subjects exposed to a given situation or
factor; usually prospective
case-control: retrospective comparison of patients with a disease to healthy
controls; frequency of certain exposures in both groups is considered
How do you calculate the odds ratio?
Ans: (A/B)/(C/D)
expresses the odds of exposure among patients with a disease compared with odds
of exposure among patients wo a disease
What does an RR val of 1 mean?
Ans: RR = 1 means that there is NO relationship between exposure and disease
What does RR <1 mean?
Ans: RR <1 suggests a negative relationship between exposure and disease
(exposure prevents disease)
What does RR >1 mean?
COMLEX II: Statistics Questions and
Verified Answers
How do you calculate relative risk?
Ans: [A/(A+B)]/[C/(C+D)]
expresses the risk of disease in people exposed to a given factor
What type of study uses relative risk to evaluate conclusions?
Ans: cohort study
what type of study uses odds ratio to evaluate conclusions?
Ans: case-control study
what is the difference between case-control and cohort studies?
Ans: cohort study: examines a group of subjects exposed to a given situation or
factor; usually prospective
case-control: retrospective comparison of patients with a disease to healthy
controls; frequency of certain exposures in both groups is considered
How do you calculate the odds ratio?
Ans: (A/B)/(C/D)
expresses the odds of exposure among patients with a disease compared with odds
of exposure among patients wo a disease
What does an RR val of 1 mean?
Ans: RR = 1 means that there is NO relationship between exposure and disease
What does RR <1 mean?
Ans: RR <1 suggests a negative relationship between exposure and disease
(exposure prevents disease)
What does RR >1 mean?
