NBME CBSE REAL EXAM 200 QUESTIONS AND ANSWERS LATEST (usmle step 1)MEDICAL EXAMINATION

NBME CBSE REAL EXAM 200 QUESTIONS AND ANSWERS LATEST (usmle
step 1)MEDICAL EXAMINATION
What is a case series? - AnswersDescription of clinical findings/symptoms for several patients with the
same diagnosis, treatment, or outcome.
What is a cross-sectional study? - AnswersAssesses the frequency of disease and risk-related factors in
the present.
What is a case-control study? - AnswersRetrospectively compares a group of people with a disease to a
group without the disease to determine if odds of prior exposure/risk factor differ.
What is a cohort study? - AnswersCompares a group of people with a given exposure/risk factor to a
group without exposure to determine if the exposure/risk factor is associated with later development of
disease.
What is a twin concordance study? - AnswersCompares the frequency with which both monozygotic
twins vs both dizygotic twins develop the same disease to measure heritability and influence of
environmental factors.
What is an adoption study? - AnswersCompares behavioral traits/genetics in siblings raised by biological
vs adoptive parents to measure heritability and influence of environmental factors.
What is an ecological study? - AnswersCompares the frequency of disease and risk-related factors across
populations to measure population data (not applicable to individuals).
What is a clinic therapeutic trial? - AnswersAn experimental study involving humans that compares the
benefits of two or more interventions.
What are the criteria for a high-quality clinical trial? - AnswersRandomized, controlled, and doubleblinded
What is a crossover clinical trial? - AnswersCompares the effect of multiple treatments on a subject
What is the purpose of randomizing the order of treatments in a crossover trial? - AnswersTo avoid bias
What is a washout period in a crossover trial? - AnswersA period between treatments to eliminate any
lingering effects
What is the advantage of using a crossover trial? - AnswersSubjects serve as their own controls
What is the intention-to-treat analysis? - AnswersAnalyzing all subjects according to their original
assigned treatment
What is the purpose of intention-to-treat analysis? - AnswersTo avoid bias from attrition, crossover, and
noncompliance
What is the disadvantage of intention-to-treat analysis? - AnswersMay dilute the true effects of the
intervention
What is the as-treated analysis? - AnswersAnalyzing subjects according to the treatment they actually
received
What is the disadvantage of as-treated analysis? - AnswersIncreases the risk of bias
What is the per-protocol analysis? - AnswersExcluding subjects who did not complete the originally
assigned treatment