B4.027 Study Design and Protocol Development

Question 1

hierarchy of scientific evidence

Answer 1

1. meta analyses
2. systematic review
3. randomized controlled trial
4. cohort
5. case-control
6. cross sectional/ecologic
7. case series/ case report

Question 2

features of randomized controlled trial

Answer 2

prospective exposure and outcome observation
concurrent control group
test for causal relationships

Question 3

features of cohort studies

Answer 3

observational study
investigators select subjects based on existing exposure status
direction of inquiry is forward in time

Question 4

what is prospective/retrospective vs forward directional/backward directional

Answer 4

prospective/retrospective indicated when the cohort is identified relative to the observation of the outcome
forward/backward directional refers to when the exposure is observed relative to the outcome

Question 5

features of a case control study

Answer 5

observational study
investigators select study subjects based on existing outcome status
direction of inquiry is backward in time to determine exposure
retrospective exposure and outcome observation

Question 6

features of a cross sectional study

Answer 6

descriptive study designed to assess the association between an exposure and outcome
selection of study subjects based on both their exposure and outcome, no direction of inquiry

Question 7

features of an ecological study

Answer 7

descriptive study where measurements are on defined groups rather than individuals
exposures and outcomes from existing data sets are averages for aggregate data
examines associations between average exposure levels and overall outcome rates at the group level

Question 8

most common study design for new tests? ie syphilis rapid screen

Answer 8

cross sectional
comparing tests not treatment
concurrent usage, no directionality

Question 9

good for rare outcomes?

Answer 9

case-control