Flashcards in RESS Deck (55):

1

## What is the scientific method?

###
Observation

Propose or modify hypothesis

Test hypothesis

Reject hypothesis and modify it

OR not reject hypothesis and re-test

2

## Is there truth in science?

### No

3

## What are the 3 requirements of a health outcome?

### Validity, reliability, responsiveness

4

## What is validity?

### Whether it accurately measures what it purports to measure

5

## What is reliability?

### Same result if retest?

6

## What is responsiveness?

### Does it detect changes when they occur?

7

## Definition of a fact?

### Confirmed to such a degree that disagreement would be perverse

8

## Definition of a hypothesis?

### A testable statement that describes an observation

9

## How do you verify a hypothesis?

### Not falsifying it

10

## 4 things a hypothesis must be?

###
Plausible

Testable

Have direction

Precise

11

## Economics is about limited ______ and unlimited_____?

###
Resources

'Wants'

12

## What is opportunity cost?

### Choosing A over B means giving up B

13

## What is technical efficiency?

### What is the best way to deliver a programme?

14

## What is allocative efficiency?

### Producing something that matches demand

15

## Resources being allocated between activities in such a way as to maximise benefit is called?

### Economic efficiency

16

## What is the 'margin' in economics?

### The next step

17

## What are the marginal benefits and costs?

### The benefits and costs of taking the next step

18

## Does efficiency consider WHO benefits?

### No

19

## What is equity?

### Fairness or justice of the distributions

20

## What is the cost and what is the outcome for cost benefit?

### Both are monetary value

21

## What is the cost and what is the outcome for cost effectiveness

###
Cost: monetary value

Outcome: Natural units e.g. life years saved

22

## What is the cost and what is the outcome for cost utility?

###
Cost: monetary value

Outcome: utility values e.g. QALYs

23

## What type of cost analysis do NICE use?

### Cost utility analysis

24

## What is EQ-5D?

### Way of finding out QALYs, a survey that uses country specific data for its algorithm

25

## What perspectives might be considered in determining cost perspective?

###
Societal (absence from work etc)

Health care system

26

## Cost effectiveness ratio =?

### Cost/QALYs

27

## What is the incremental cost effectiveness ratio?

### Change in cost/ change in effectiveness

28

## What does a cost-effectiveness acceptability curve show?

###
The probability that the intervention is cost effective compared with the alternative.

Cost effectiveness threshold aka willingness to pay

against

probability

29

## In normal distribution which average is used?

### Mean and SD

30

## In skewed distribution which average is used?

### Median and IQR

31

## What graph do you use to find the distribution of a continuous variable?

### Histogram

32

## Mortality=?

### Number dying from the disease/number dying in the period

33

## Case fatality=?

### Number dying from the disease/number with the disease (in the period)

34

## A risk ratio of 1 would indicate what?

### The exposure has no impact

35

## A risk ratio of more than 1 =?

### Exposure is harmful

36

## What is the P value?

### Probability that the results were due to the hypothesis (rather than chance)

37

## Effect size

### A quantitative measure of the strength of a phenomenon

38

## What is a confidence interval

### X% (normally 95%) certain that the true population mean falls within a specified range e.g. +-0.05

39

## Correlation should not be used in which 5 cases?

###
1. There is a non-linear relationship between variables

2. There are outliers

3. There are distinct sub-groups, for example, if we mix two samples together such as healthy controls and disease cases

4. One or both of the variables is not normally distributed. 5. One or both of the variables is non-numeric.

40

## Calculation of a risk ratio requires? And so what sort of study can this be used in?

###
Incidence

Cohort

41

## Risk ratio is a measure of

### Relative risk

42

## Odds are

###
number of times the event occurs divided by the number of times it does not occur.

43

## Risk/probability is?

### Number of outcomes / total number of possible outcomes

44

## What is the odds ratio for?

### Represents the relative risk for a case-control study (when there is no incidence.)

45

## Linear regression allows us to?

### Make predictions

46

## What is the null hypothesis of the chi-squared test

### That there is no relationship between the variables

47

## When can chi-squared not be used?

### Small sample size- it is too likely to reject the null hypothesis in this case (but a correction can be used)

48

## If P is more than what value can you not reject the null hypothesis in a chi-squared test?

### 0.05

49

## What is a 'failure' in a study?

### Someone leaving/dying etc.

50

## Leaving the study before the event occurs, or entering the study after the start of the study, is known as ?

### Censoring

51

## Right censored data occurs when....?

### the people in the study did not reach a failure before the end of the study.

52

## Left censoring is when....?

###
We are not certain what happened to people before the time at which they entered the study.

A common example is when people already have the disease of interest when the study starts.

53

## The survival function is defined as....?

### the chance of survival until a certain time

54

## The hazard function is defined as....?

### the chance of instantaneous failure at any one time

55