Flashcards in Measures of Frequency, Association and Impact Deck (28)

Loading flashcards...

1

## What are the basic measures?

###
Count- no comparison

Proportion

Odds- 4:1

Rate- needs time

2

## What are the two most important measures of frequency?

###
Incidence

Prevalence

3

## What is the difference between incidence and prevalence?

### Incidence is frequency of new cases during a period where as prevalence is the proportion of all animals in a specific time

4

## What is the commonly used measures of incidence?

### Cumulative incidence/ incidence risk

5

## What does incidence show about a disease?

### The amount of risk of contracting the disease

6

## What is needed for incidence?

### A clear case definition, surveillance programme which identifies cases, to show its a new case

7

## What is cumulative incidence?

### The proportion of disease-free individuals developing a given disease over a specified time

8

## How is cumulative incidence calculated?

###
Number of new cases during period/

population at risk during same period

9

## How is prevalence calculated?

###
Number of cases at time/

total number of animals at risk at time

10

## What is the difference between point and period prevalence?

### Point is a single point in time, period is number of cases over defined period of time

11

## What does prevalence show about a disease?

### How widespread a disease is

12

## What is needed for prevalence?

### Cross sectional studies, no idea about temporality

13

## How does duration of a disease effect incidence and prevalence?

###
High incidence but short duration causes low prevalence

Low incidence but long duration causes high prevalence

14

## What are measures of association used to assess?

### The magnitude of the relationship between risk factor and outcome

15

## What are the 2 types of relative measures?

### Relative risk, odds ratio

16

## What are the 2 types of absolute measures?

### Risk difference, attributable fraction,

17

## What kind os studies are used for relative risk?

### Cohort and cross sectional

18

## How is the relative risk ratio calculated?

###
risk of disease in exposed/

risk of disease in unexposed

19

## What does relative risk measure?

### The strength of association

20

## What is odds?

### The probability of an event occurring divided by the probability of the event not occurring

21

## How is odds ratio calculated?

###
Odds of disease in exposed/

Odds of disease in non-exposed

22

## How can odds be interchanged?

### Odds of exposure can be used

23

## What king of studies is odds ratio used?

### Case-control studies

24

## What does it mean if the RR/OR are below 1, equal to 1, over 1?

###
<1- decreased risk

=1- no change

>1- increased risk

25

## What can make a RR/OR insignificant?

### If the confidence interval crosses 1

26

## What is the problem of measures of association?

### Don't show the frequency of disease or the amount of disease that results

27

## What is the measure of impact of exposed?

### Attributable risk

28