Lesson 4

Question 1

What are some interchangeable terms for S.E.P?

Answer 1

Social class, social stratification, socio-economic background, socio-economic status (SES)

Question 2

What is S.E.P?

Answer 2

Social and economic factors which affect the position where groups or individuals stand, within the societal structure.

The determinants must be objective, measurable and meaningful

Question 3

What are some of the determinants regarding S.E.P?

Answer 3

Income, Education, Occupation, NEET (NOT in education employment, or training)

Question 4

Why measure S.E.P?

Answer 4

SEP is used to quantify the level of inequality within or between societies
May highlight changes to population structures over time, between census periods or even between generations.

Question 5

How is S.E.P measured for individuals? (E.I.O.H.A)

Answer 5

Education (more likely to take on board health issues and messages)

Income- more material goods

Occupation- status and power

Housing

-Assets and Wealth

Question 6

How is S.E.P measured for populations?

Answer 6

Area measures
i.e deprivation and access
Who has the best access why and how?

Population Measures
income inequality
Literacy Rates
GDP ( gross domestic product per capita

Question 7

Advantages and disadvantages of each individual determinant of S.E.P?

Answer 7

Income = sensitive topic

Education = Usually easier to obtain (less sensitive)
Different standard in different countries or population

Occupation =Hard to determine which occupation should be measured (e.g. should past occupation be taken into account?)
Can see social mobility

Question 8

Which measure of S.E.P is the best/gold-standard?

Answer 8

There is no gold standard!

Income is the best option

Question 9

What does screening in health involve?

Answer 9

Screening involves identifying risk factors for disease or unrecognised disease by applying tests on a large scale to a population

Question 10

What is the screening criteria?

Answer 10

Suitable test, suitable treatment, suitable screening programme

Question 11

Why do we need the screening criteria?

Answer 11

Not enough money in the health care system to fund every single health problem, so the screening helps us to decide what does get screened and how

Question 12

How is a suitable disease determined?

Answer 12

1. Relatively common or uncommon (early detection leads to better outcome)
2. Knowledge of the natural history of disease.

Question 13

Is screening women for alcohol intake to prevent breast cancer primary, secondary or tertiary?

Answer 13

Primary

Dealing with a risk factor- screening for alcohol intake to prevent breast cancer.

Question 14

Is screening for bone density following chemotherapy for breast cancer primary, secondary or tertiary?

Answer 14

Tertiary
After clinical diagnosis- have had treatment. They are screening for bone density which is a complication of breast cancer.

Question 15

Is breast cancer screening primary, secondary or tertiary?

Answer 15

Secondary

Is to prevent further complications.

Question 16

What are the two measures of accuracy in a screening test?

Answer 16

Sensitivity and specificity

Question 17

Define sensitivity:

Answer 17

The ability of the test to correctly identify those who have the disease (a), from all individuals with the disease (a+b)

Represents the likelihood of a + test in those who have the disease

Question 18

How is sensitivity calculated?

Answer 18

a / a+b x 100%

(True positives / those with disease) x 100%

Question 19

Define specificity?

Answer 19

The ability of the test to correctly identify those who do NOT have the disease (d), from the individuals free from the disease (b+d)

Represents the likelihood of a – test in those who do NOT have the disease

Question 20

How is specificity calculated?

Answer 20

d / b+d x 100%

(True negatives / those without disease) x 100%

Question 21

Are sensitivity and specificity fixed characteristics?

Answer 21

Yes!

Think of it as how good the test actually is, and the science behind it!

Question 22

When is the sensitivity of a screening test high?

Answer 22

If the proportion of true positives (a) is high.

Question 23

When is the specificity of a screening test high?

Answer 23

if the proportion of true negatives (d) is high.

Question 24

What do the predictive values show?

Answer 24

Are a reflection of the proportion of disease in the population AND a reflection of the ability of the screening test to detect a +/- result

Question 25

What is the positive predictive value?

Answer 25

The proportion who actually have the disease, of those who tested positive

Represents the probability of having the disease if tested positive

Question 26

How is PPV calculated?

Answer 26

a / a+b x 100%

(True positives / those tested positive) x 100%

Question 27

What is the Negative predictive value?

Answer 27

The proportion who actually do NOT have the disease, of those who tested negative

Represents the probability of NOT having the disease if tested negative

Question 28

How is NPV calculated?

Answer 28

d / c+d x 100%

(True negatives / those tested negative) x 100%

Question 29

Are PPV and NPV fixed characteristics of the test?

Answer 29

No!
They reflect both test accuracy AND prevalence of the disease!
Depends on both specificity and sensitivity and the prevalence of disease in a population

Question 30

What are the negative aspects of screening tests?

Answer 30

Lead time bias

Length time bias

Question 31

What is lead time bias?

Answer 31

Apparent increase in lead time or life expectancy, when you only actually ‘lengthened’ the time between where is disease is detectable by screening and clinical diagnosis
(The whole time line is the same length overall!)

Question 32

What is length time bias?

Answer 32

We are only picking up and identifying patients with slower progressive disease (Mean survival time appears to be longer than those rapidly progressive disease as they were not actually included in the tests!)

Question 33

What is population attributable risk?

Answer 33

The amount of extra disease attributable to a risk factor in a population

Question 34

How is attributable risk calculated?

Answer 34

AR = R.D

EGO - CGO

Question 35

What does attributable risk reflect?

Answer 35

Represents the amount of disease we could prevent if we removed the risk factor from the exposure group.

Question 36

What is population attributable risk?

Answer 36

The amount of extra disease attributable to a risk factor in a particular population

Question 37

How is PAR calculated?

Answer 37

PGO – CGO

(a+b)/P – CGO

Question 38

What does PAR represent?

Answer 38

Represents the amount of disease we could prevent if we removed the risk factor from the whole population.