Different types of scientific evidence

Question 1

Define exposure

Answer 1

Any factor expected to cause a change/ outcome in those exposed
(independent variable)

Question 2

Studies without an exposure are called?

Answer 2

Case series/studies

Question 3

Observational vs interventional studies

Answer 3

Observational studies - the investigator observes what happens without intervening

Interventional studies - the investigator makes an intervention then studies the effects

Question 4

Define outcome

Answer 4

A change expected to occur in response to an exposure

dependent variable

Question 5

Prospective vs retrospective studies

Answer 5

Prospective studies: a exposure (intervention) is made or identified (observational), then people are followed forward to see what will happen (outcome)

Whereas

retrospective studies: people with a specified outcome are identified, then traced back to see if a previous exposure has occurred (observational)

Question 6

cross sectional vs longitudinal

Answer 6

Cross-sectional: measurements are made at a single time point

Longitudinal: measurements are made repeatedly at different time points

Question 7

How is a systematic review done?

Answer 7

All clinical trials addressing a specific question are identified
the data is put together to give stronger signal to answer the questions that the individual trials indicated