3 and 4

Question 1

What is epidemiology

Answer 1

study of distribution and determinants of a disease

Question 2

What are incidence rates

Answer 2

the number of new cases

Question 3

what are prevalence rates

Answer 3

the number of cases at a given point in time

Question 4

what is the iceberg phenomenon

Answer 4

asymptomatic people aren’t being counted

Question 5

risk factor criteria

Answer 5

1. temporal relation
2. dose response
3. strength of association
4. consistency
5. biological sense

Question 6

Prevention

Answer 6

primary - before you have the disease, keeping it away
secondary - symptoms have started, but you try to keep them down
tertiary - you have the disease, are just trying to manage the symptoms, and rehabilitate

Question 7

What are experimental studies

Answer 7

when the operator changes certain variables and studies the outcome

Question 8

what are observational studies

Answer 8

when the operator simply observes what is going on

Question 9

what are the types of descriptive studies

Answer 9

case reports
case series
correlational/ecological
cross sectional surveys

Question 10

what is a case report

Answer 10

a study of a single individual

Question 11

what is a case series

Answer 11

a study of a few individuals with unusual symptoms or conditions

Question 12

what is a correlational/ecological study

Answer 12

when rates are studied and you look for correlations

Question 13

what is a cross sectional survey

Answer 13

a survey of the general population at a single point in time

Question 14

what is a case control study

Answer 14

a study in which you focus on people with the disease, and look into the past for common exposures

Question 15

what is a cohort study

Answer 15

a study in which you focus on people with a certain exposure and observe them periodically

Question 16

what is a Quasi-experimental study

Answer 16

a study in which the operator changes variables but no control group is present

Question 17

what is a true-experimental study

Answer 17

a study in which the operator changes variables and has a control group for comparisons

Question 18

hierarchy of evidene

Answer 18

1. metaanalysis/systematic review
2. randomized clinical trial
3. cohort study
4. case control
5. case series
6. case reports

Question 19

What is quantitative data

Answer 19

numerical data

Question 20

what is continuous quantitative data

Answer 20

numerical data for which all values are possible

Question 21

what is discrete quantitative data

Answer 21

numerical data for which only certain values are possible

Question 22

what is categorical data

Answer 22

data that falls into categories, can’t be quantified

Question 23

what is non-ordinal or nominal categorical data

Answer 23

data that falls into categories, but those categories are in no particular order

Question 24

what is ordinal categorical data

Answer 24

data that falls into categories, and those categories have a sort of order

Question 25

What are the descriptive statistics for quantitative data

Answer 25

mean - average median - middle number when in numerical order mode - most common value standard deviation - average variation from the average square root of the variance

Question 26

what are the descriptive statistics for categorical data

Answer 26

frequency - # of outcomes in that category | percentage - # of outcomes in that category per 100

Question 27

what are the four types of sampling

Answer 27

convenience - using the most convenient group random - stratified - systematic

Question 28

What is the null hypothesis

Answer 28

the hypothesis that is being tested declares no difference, or no effect rejecting the null happens when p < or = .05 fail to reject the null happens when p> .05

Question 29

What is the alternate hypothesis

Answer 29

the hypothesis that the researcher thinks they are studying | usually declares that there is a difference, or that there is an effect.

Question 30

what is a type 1 error

Answer 30

false positive | rejecting the null when you shouldn't

Question 31

what is a type 2 error

Answer 31

false negative | failing to reject the null when you should

Question 32

What is the p value

Answer 32

the probability that a difference occurred by chance alone and isn't a true difference

Question 33

What are confidence intervals

Answer 33

usually listed at 95%, indicates the probability that the CI contains the true population parameter

Question 34

What does it mean if the CI (confidence interval) passes through 1

Answer 34

that it is not significant

Question 35

What tests are used on quantitative data

Answer 35

T-Tests (used to compare differences in TWO groups) ANOVA Linear regression

Question 36

What are the types of T-tests

Answer 36

one sample T-test - single population vs. known two sample T-test - two sample populations matched pair T-test - single group measured at two points

Question 37

What is an ANOVA test for

Answer 37

a test two determine if differences between more that two groups are statistically different

Question 38

what is a linear regression used for

Answer 38

Correlation

Question 39

what is the symbol for correlation and what do its values mean

Answer 39

r it can be from -1 to 1, the further from 0 the more strongly correlated they are. when r=0 it means there is no correlation

Question 40

What does the square of the correlation tell us (r^2)

Answer 40

how likely things will fit to the line

Question 41

What are the analyses for categorical data

Answer 41

Chi square logistic regresssion Odds ratio

Question 42

When is a chi square analysis used

Answer 42

on categorical data when comparing proportions of two groups with dichomotus outcomes

Question 43

What does the odds ratio tell us

Answer 43

odds difference between those exposed and those not exposed

Question 44

what does an OR of 1 =

Answer 44

no difference between groups

Question 45

What does an OR >1 =

Answer 45

it shows an increased risk (higher OR = higher risk)

Question 46

what does an OR < 1 =

Answer 46

it shows it as protective

Question 47

What does a CI that goes through 1 mean

Answer 47

that it is not significant

Question 48

What does validity tell you

Answer 48

whether or not the study is good at finding what you are looking for

Question 49

what is external validity

Answer 49

does the study fit the patients

Question 50

What is internal validity

Answer 50

is the study well designed

Question 51

what is sensitivity

Answer 51

does it detect a difference when there is a difference

Question 52

what is specificity

Answer 52

does it detect no difference when there isn't a difference

Question 53

What is reliability

Answer 53

is it reproducable, repeatable

Question 54

What is Bias

Answer 54

systematic error resulting in incorrect estimates

Question 55

what is selection bias

Answer 55

inappropriate selection and assignment to groups

Question 56

what is a recall bias

Answer 56

when those studied incorrectly recall past events

Question 57

what is confounding

Answer 57

a third variable that is hard to tease out and can affect your dependent variable