Experimental Design

Question 1

what is a case report or case series?

Answer 1

A report on a single patient or a single treatment/intervention or small set of patients without any control groups

Question 2

What is a Case-control study?

prevalence of exposure > in (cases) than (controls)

Answer 2

Study patients with a specific condition compared with people who do not have the condition; less reliable than randomized controlled trials. Both groups are expose to a factor

Question 3

what are the pros of a Case-control study?

Answer 3

• Fairly easy and cost-effective
• Tend to support, but not prove causal hypotheses

Question 4

1.

what are Observational Cohort studies?

Answer 4

Evaluate and follow patients who have a specific exposure or receive a particular treatment over time and compare them with another group that is similar but has not been affected by the exposure being studied

Question 5

What are the pros of Observational Cohort studies?

Answer 5

Best method for determining the incidence and natural history of a condition
- Determine whether there is an association between a factor and development of disease
- Derive inferences appropriate regarding possible causal relationships

Question 6

what means that a study is double blinded?

Answer 6

both the investigators and the subjects do not know whether they received an active medication or a placebo

Question 7

what are Randomized controlled trials (RCTs)?

Answer 7

Subjects are randomly assigned to a treatment or a control group that received placebo or no treatment; only difference between the two groups is the intervention being studied.

Can be single or double blinded

Question 8

what are the study phases?

Answer 8

Phase I
- Small N
- Toxic and pharmacologic effects
Phase II:
- Larger N
- Safety and efficacy studies
Phase III (RCT)
- Large scale randomized controlled trials
- Effectiveness and relative safety
- Often multicenter
- Certain side effects may not be evident for years
Phase IV
- Postmarketing surveillance
- Important for monitoring new agents as they come into general use by public

Question 9

What are the pros of Randomized controlled trials (RCTs)?

Answer 9

-RCTs are the gold standard design to test therapeutic interventions
- Determine whether the intervention had a significant impact relative to the no-intervention
group. Best for: Determining cause-effect
- Studying definable treatments or exposures