Lecture 1and 2 - Quant methods - Case controls studies

Question 1

2 goals of descriptive studies

Answer 1

1. generate hypos

2. Assess or estimate prevalence or incidence

Question 2

2 goals of analytic reseach

Answer 2

1. tests hypotheses

2. assess association between exposure and outcome

Question 3

def. cases

Answer 3

clearly defined and shown to have the disease in question

Question 4

def. controls

Answer 4

clearly defined and shown to be free of the disease

Question 5

steps to conduct a case control trial

Answer 5

1. start with outcome
2. sample people with disease (cases)
3. sample people without (controls)
4. assess exposure Hx

Question 6

main adv. and dis

Answer 6

adv
- good for rare outcomes
dis
- bias can be high

Question 7

how to tell you are looking at a case control

Answer 7

look at sampling - is it cases and controls?

Question 8

what is analysis of case contols

Answer 8

• look back to measure the probablity of exposure given disease
• cannot calculate incidence
• calculate ORs that with low prevalence can estimate the RR

Question 9

weaknesses

Answer 9

1. bias in selection of controls
2. recall bias among participants
3. can only study one disease
4. cannot estimate incidence
5. cannot prove temporal relat.