Introduction and Causal Concepts

Question 1

Epidemiologists seek to identify ______ and evaluate _________ with various _______ of interest

Answer 1

• exposures (demographic, infectious, toxic, nutritional, lifestyle
• associations
• outcomes

Question 2

Generalized inferences about ‘causation’ based on repeated observations

Answer 2

Inductive Reasoning

Question 3

Starts with hypothesis and makes observations to either prove or refute assumptions

Answer 3

Deductive Reasoning

Question 4

Factor always present with disease

Answer 4

component cause (necessary cause

Question 5

Factor is present, disease invariably follows

Answer 5

sufficient cause (very few are sufficient themselves)

Question 6

Causal Web model Causes

Answer 6

Direct (ex. toxin)

Indirect (exposure on outcome mediated through intervening variables)

Question 7

Counterfactual (Potential Outcomes)

Answer 7

Exposed vs. Non-exposed

Question 8

Census = ________ evaluated

Answer 8

Everyone

Question 9

Sample = data collected from _____ of population

Answer 9

subset

Question 10

Descriptive Study

Answer 10

describes population

Question 11

Analytic

Answer 11

estimate magnitude of association b/w outcome and exposures

Question 12

Target population

Answer 12

extrapolate results from in a study

Question 13

source population

Answer 13

pop. study subjects were drawn

Question 14

study sample

Answer 14

indie that end up in study

Question 15

sampling frame

Answer 15

list of all sampling units in source pop.

Question 16

association exist when in fact it doesn’t

Answer 16

Type 1 (alpha) error

Question 17

outcome aren’t different when they are

Answer 17

Type 2 (beta) error

Question 18

judgement of investigator sample is representative of pop

Answer 18

judgement sampling

Question 19

easy to obtain sample

Answer 19

convenience

Question 20

subject possesses one or more attributes known to exposure

Answer 20

purposive sampling

Question 21

every element in pop. has a non-zero prob of being in study

Answer 21

random selection (probability sampling)

Question 22

Simple Random

Answer 22

Every study subject in source pop has the same chance

Question 23

systematic random

Answer 23

study pop size / required sample size

Question 24

stratified random (Proportional)

Answer 24

sampled in each stratum is proportional to total number in each stratum

Question 25

Cluster sampling

Answer 25

natural collection of study subjects

Question 26

multistage sampling

Answer 26

secondary sampling unit is selected from a cluster

Question 27

targeted (risk-based) sampling

Answer 27

sample only from strata with probability of disease