Public Health

Question 1

Define incidence

Answer 1

Number of new cases of a disease/condition in a population per unit time

Question 2

Define prevalnce

Answer 2

Number of existing cases of a disease/condition in a population at a given point in time

Question 3

What are the 5 stages of change?

Answer 3

Pre-contemplation
Contemplation
Preparation
Action
Maintenance

Question 4

What is the aim of a primary intervention?

Answer 4

It aims to prevent the onset of a disease and involves interventions that are applied before any evidence of disease is present e.g. vaccines

Question 5

What is the aim of a secondary intervention?

Answer 5

Detection of disease in earliest stages before symptoms are present and intervening to slow, stop or reverse disease progression e.g. breast cancer screening

Question 6

What is the aim of a tertiary prevention?

Answer 6

Interventions designed to arrest the progress of established disease and minimise its negative consequences

Question 7

What is screening?

Answer 7

A process which identifies apparently well individuals who may be at increased risk of developing a condition

Question 8

What is selection bias?

Answer 8

A systematic error in selection/allocation of study participants

Question 9

What is screening?

Answer 9

A process which identifies apparently well individuals who may be at increased risk of developing a condition, in the early stages of a condition so that intervention can alter the disease course thereby reducing morbidity and mortality

Question 10

What is a true negative?

Answer 10

A result that is negative and the patient has not got the disease

Question 11

What is a false positive?

Answer 11

A positive result but the patient does not have the disease

Question 12

What is a false negative?

Answer 12

A negative result but the patient does have the disease

Question 13

Define sensitivity

Answer 13

Ability of a test to correctly identify those with the disease
A/A+C

Question 14

Define specificity

Answer 14

Ability of a test to correctly identify those without the disease
B/B+D

Question 15

Define positive predicted value

Answer 15

The proportion of the positive results that are true positives
A/A+B

Question 16

Define negative predicted value

Answer 16

The proportion of the negative results that are true negatives
D/D+C

Question 17

What are the limitations of using PSA as a screening test?

Answer 17

Raised in BPH, prostatitis, after ejaculation, bike riding

Question 18

What are the limitations of using a D-dimer to detect PE?

Answer 18

It can be raised due to other conditions

Question 19

What is absolute risk?

Answer 19

The risk of developing risk over a time period

Question 20

What is relative risk?

Answer 20

Risk of getting a disease in an exposed group compared to an unexposed group. It’s a ratio so has no units

Question 21

What’s attributable risk?

Answer 21

AKA absolute risk reduction
Rate of disease in exposed that may be attributed to exposure
Incidence in exposed - incidence in unexposed

Question 22

Define number needed to treat

Answer 22

The number of people need to be treated for one person to benefit
NNT= 1/ARR

Question 23

Define a never event

Answer 23

A serious, largely avoidable patient safety event which should not occur if the available preventative measures have been implemented

Question 24

Give some examples of a never event

Answer 24

Wrong patient 
Wrong site surgery 
Wrong drug dose
Foreign body retained
Mental health: escape of transfer patient 
ABO incompatibility

Question 25

What is neglect?

Answer 25

Falling below the acceptable standard of care

A breach of the legal duty of care owed which results in harm to that patient

Question 26

What is the Swiss cheese model?

Answer 26

Each layer represents processes which have been put in place to prevent errors happening. Holes are where processes fail. When the holes in the cheese line up an error can occur.

Question 27

What are the two types of error?

Answer 27

Errors of commission - doing something

Errors of omission - not doing something

Question 28

What are the 5 factors affecting patient compliance?

Answer 28

Socioeconomic - long distance from treatment setting
Health system - supply of medication
Condition - memory impairment 
Therapy - complex treatment regimens
Patient - disbelief/denial of condition

Question 29

What are the two tests to determine negligence?

Answer 29

Bolam - would a group of reasonable doctors have done the same?
Bolitho - would it have reasonable for them to do so?

Question 30

What are the principles of treatment for substance misuse interventions?

Answer 30

Minimise harm e.g. decrease risk of blood borne viruses
Substitute prescribing e.g. methadone 
Psychosocial interventions
Residential treatment 
Self-help groups

Question 31

What are the 3 times you can break confidentiality?

Answer 31

If they’re a risk to the public - intend to commit a crime
If they have given consent
If it is required by law - notifiable disease, a judge orders you to do so
You should always try to obtain consent

Question 32

Define epidemic

Answer 32

An increase in the prevalence of a disease above the number usually observed in the population in a particular area

Question 33

Define pandemic

Answer 33

An epidemic which occurs in several countries or continents

Question 34

What is information bias?

Answer 34

A systematic error in measurement/classification of exposure or outcome

Question 35

List 3 examples of screening programs.

Answer 35

Bowel cancer - FOB
Breast cancer - mammograms
Cervical cancer - smear and HPV testing 
AAA
Foetal anomaly screening program
Diabetic eye screening