Study Design — Flashcards

Flashcard 71: Survival Cohort Bias is a special case of _____ where as survival cohort (available patients) is used instead of a(n) true inception cohort

Answer: assembly bias

Flashcard 72: Antigenic drift is associated with _____-demics

Answer: epi

Flashcard 73: Regarding the incidence of the three main types of skin cancer in the United States, _____ > _____ >> _____

Answer: Basal

Flashcard 74: When do you use a CIR? - when there is a(n) _____ population that is starting at a common point in time - when an outcome can occur only once - and when when disease event rates are relatively stable over time

Answer: fixed or closed

Flashcard 75: Lung cancer is the _____ most common cancer by incidence

Answer: 2nd

Flashcard 76: Odds are the _____ of the probability of having an event to the probability of not having the event.

Answer: ratio

Extra: Ex. if odds of event X occurring are 1:9, event X will occur once for every nine times it will not (in 10 events, X will occur once)

Flashcard 77: One assumption of Hardy-Weinberg population genetics is that no _____ have occurred at the locus

Answer: mutations

Flashcard 78: Is probability a proportion or a ratio? _____

Answer: Proportion

Flashcard 79: A study finds the correlation coefficient between plasma homocysteine levels and folic acid intake to be -.8 (p <0.01). How much of the variability in plasma homocysteine levels is explained by folic acid intake? _____

Answer: 64%

Extra: The coefficient of determination ($r^2$) represents the proportion of the variance in the dependent variable that is explained by the independent variable.

Flashcard 80: A study design in which each participant serves as their own control by receiving a sequence of different treatments is a(n) _____ study.

Answer: cross-over

Extra: A washout period is typically required between treatments to prevent carryover effects.