Week 7 Flashcards
what is a time-to-event study?
how do you create a survival curve? (what is the official name of this type of curve)
of ppl who had outcome at certain point divided by # of ppl still in study at that time (Kaplan-Meier Curve)
length of time to any “event” or outcome of interest (death, cancer, pregnancy, etc)
or
mean survival time (between a duration of time, how many events happened during that time)
define what a Kaplan-Meier Survival Curve is
an illustrative curve based on all follow-up data which estimates probability of survival
describe what a parallel-group RCT is
takes individual subjects and divides them into the experimental group and control group and both groups are evaluated based on if they had the outcome or did not have the outcome
describe what a cluster RCT is
involves the selection of a specific group of subjects for randomization such as a hospital or clinic.
AKA known as: community trial, group randomized trial
describe what a crossover RCT is
subjects are placed into either the treatment group or control group and data is recorded until the FIRST end of the trial. then a washout period occurs to ensure drug is out of pts system and then subjects are swapped into the other group they weren’t in before and evaluated
what is a main disadvantage of crossover RCTs?
they cannot test for cures, mortality or prevention of disease, only outcomes such as lab values (like blood pressure)
describe what a factorial RCT is
studying more than 1 drug treatment in one study, including: Drug a + control, Drug B + control, Drug a + Drug b, and Control groups to evaluate combo therapies
what is a “Quasi-experimental” trial?
a trial commonly used for quality improvement studies (“staff training”) where the researcher decides who will be in the intervention gorup. it is not a RCT, so it is not as powerful as a RCT, but it is better than an observational study
what are the 3 main purposes of conducting RCTs? (what is the trial trying to prove in regards to the study?)
superiority trials (proving the intervention is superior)
equivalence trials (proving the intervention is equivalent)
inferiority trials (proving the intervention is not inferior)
** in regards to old drug or placebo
what is “Delta” used for in equivalence/inferiority trials?
Delta is considered a hypothetical margin interval showing where the treatment aligns respective to it’s equivalence or non-inferiority
*for non-inferiority trials, both per protocol and intention-to-treat analyses should be used for proper interpretation
which studies have the highest level of significance?
systematic reviews and meta-analyses
