Public health

Question 1

What are the 3 types of prevention?

Answer 1

1. Primary: stopping disease from occurring e.g. vaccines
2. Secondary: detecting a disease early e.g. screening
3. Stopping disease from progressing e.g. diabetic foot care, stroke rehab

Question 2

What is the preventative paradox?

Answer 2

A preventative measure which brings much benefit to the population often offers little to each participating individual.
I.e. it’s about screening a large number of people to help a small number of people.

Question 3

What does sensitivity mean?

Answer 3

the proportion of people with the disease who are correctly identified by the screening test.

Question 4

What does specificity mean?

Answer 4

the proportion of people without the disease who are correctly excluded by the screening test.

Question 5

PPV vs NPV?

Answer 5

PPV: the proportion with a positive test result who actually have the disease.
NPV: the proportion with a negative test result who do not have the disease.

Question 6

What is the wilson + jugner criteria for screening?

Answer 6

1. The condition should be an important health problem
2. Treatment should be available
3. Facilities for diagnosis and treatment should be available
4. There should be a recognisable latent or early symptomatic stage
5. There should be a suitable test or examination
6. The test should be acceptable to the population
7. The natural history of this condition should be understood
8. There should be a policy on whom to treat as patients
9. Costs of screening should be economically balanced
10. Screening should be a continuous project, not just one off

Question 7

Lead time bias vs length time bias?

Answer 7

Lead time : early detection results in an apparent increase in survival time
Length time: differences in the length of time taken for a condition to progress to severe effects that may affect the apparent efficacy e.g. less aggressive cancers that slowly progress are more likely to be spotted

Question 8

What are the prospective studies vs retrospective studies?

Answer 8

Prospective: cohort/RCT
Retrospective: Case control/cross-sectional/case series/case report

Question 9

Incidence vs prevalence?

Answer 9

Incidence – the number of new cases of a disease that develop in a population (e.g. per 100,000) in a given time frame (e.g. per year).
Prevalence – the total number of people in a population found to have a disease at a point in time.
Number of existing cases/population/points in time.

Question 10

What is absolute risk?

Answer 10

gives a feel for actual numbers involved i.e. it has units.
E.g. deaths/1000 population.

Question 11

What is relative risk?

Answer 11

ratio of risk of disease in the exposed to the risk in the unexposed i.e. no units.
Incidence in exposed ÷ incidence in unexposed.
Tells us about the strength of association between a risk factor + a disease.

Question 12

What is attributable risk?

Answer 12

the rate of disease in the exposed that may be attributed to the exposure.
Incidence in exposed – incidence in unexposed

Question 13

What is relative risk reduction?

Answer 13

the reduction in rate of the outcome in the intervention group relative to the control group.
(Incidence in unexposed – Incidence in exposed) ÷ incidence in unexposed.

Question 14

What is absolute risk reduction?

Answer 14

the absolute difference in the rates of events between the 2 groups. Gives an indication of the baseline risk + the intervention effect.
Incidence in unexposed – incidence in exposed

Question 15

What is odds and odds ratio?

Answer 15

The odds of an event is the ratio of the probability of an occurrence compared to the probability of a non-occurrence.
Odds = probability ÷ (1 – probability).
Odds ratio – the ratio of odds for the exposed group to the odds for the non-exposed groups.

Question 16

What are the 3 types of bias?

Answer 16

1. selection
2. information
3. publication

Question 17

What is the Bradford-hill criteria for assessing causality?

Answer 17

1. Strength - The strength of the association
2. Dose-response – does a higher exposure produce higher incidence?
3. Consistency – similar results in different studies and populations
4. Temporality – does the exposure precede the outcome
5. Reversibility – removing exposure reduced risk of disease
6. Biological plausibility – does it make sense biologically
7. Coherence – logical consistency with lab information e.g. incidence of lung cancer with increased smoking is consistent with lab evidence that tobacco is carcinogenic
8. Analogy – similarity with other established cause-effect relationships in the past e.g. thalidomide in pregnancy, not other teratogenic drugs show similar effects
9. Specificity – Relationship is specific to the outcome of interest e.g. introducing helmets reduced head injuries specifically, it wasn’t that there has been an overall lower injury rate

Strong dogs can tear really big cats apart sadly

Question 18

What is health behaviour?

Answer 18

behaviour aimed to prevent disease e.g. eating healthy

Question 19

What is illness behaviour?

Answer 19

behaviour aimed to seek rememdy e.g. going to a doctor

Question 20

What is sick role behaviour?

Answer 20

– behaviour aimed at getting well e.g. taking tablets and rest

Question 21

What 4 things influence perception of risk? (unrealistic optimism)

Answer 21

1. Lack of personal experience with the problem
2. Belief that the problem is preventable by personal action
3. Belief that if its not happened by not, its not likely to
4. Believe that the problem is infrequent

no one i know has died from smoking -> ill just sop smoking later -> nothings happen and ive been smoking 20 years -> not many people die from smoking

Question 22

What is the health belief model?

Answer 22

Perceived barriers have been demonstrated to be the most
important factor in addressing behaviour change in patients
Individuals will change if they:
1. Believe they are susceptible to the condition (perceived susceptibility)
2. Believe that it has serious consequences (perceived severity)
3. Believe that taking action reduced susceptibility (perceived benefits)
4. Believe that the costs of taking action outweigh the benefits (perceived barriers)

Question 23

What are the pros and cons of the health belief model?

Answer 23

Advantages
1. Can be applied to wide variety of health behaviours.
2. Cues to action are unique component to the model.
3. Long standing model.

Criticism
1. Does not differentiate between first time + repeat behaviour.
2. Does not consider the influence of emotions + behaviour.
3. Cues to action often missing.
4. Alternative factors may predict health behaviour such as self-efficacy or outcome expectancy (whether they feel they will be healthier as a result).

Question 24

What is the theory of planned behaviour?

Answer 24

Proposes that the best predictor of behaviour is intention to change behaviour.
Intention is determined by
1. Personal attitude to the behaviour
2. Social pressure to change behaviour (social norm)
3. Person’s perceived behavioural control

i think Smoking is bad -> people think smoking is bad -> i believe i can stop smoking

Question 25

How do you bridge the intention-behaviour gap ?

Answer 25

PPAIR 1. Perceived control (something an individual feels they are capable of doing). 2. Preparatory actions (dividing task into sub-goals increases self-efficacy + satisfaction at the point of completion). 3. Anticipated regret (reflecting on feelings once failed, related to sustained intentions). 4. Implementation intentions (biggest one, “if-then” plans): E.g. if I need to take my medication in the morning then I will place it here to remind me. 5. Relevance to self (can they relate to the behaviour).

Question 26

What are the pros and cons of the planned behaviour model?

Answer 26

Pros 1. Can be applied to wide variety of health behaviours. 2. Useful for predicting intention. 3. Takes into account importance of social pressures. Cons 1. Lack of temporal element + direction or causality, no sense of how long behaviour change may take. 2. ‘Rational choice model’ so does not take into account emotions. 3. Assumes attitudes, subjective norms + perceived behavioural control can be measured. 4. Relies on self-reported behaviour.

Question 27

What is the trans-theoretical model?

Answer 27

1. Precontemplation = no intention of stopping. 2. Contemplation = beginning to consider stopping, probably at some ill-defined time in the future. 3. Preparation = getting ready to quit in the near future, set stop date, go to doctor, throw away items (28d). 4. Action = engaged in stopping behaviour on stop date (6m). 5.Maintenance = continues + engaged with abstinent behaviour (6m).

Question 28

What are the NICE transition points?

Answer 28

Leaving school. Starting work/new job. Becoming a parent. Becoming unemployed. Retirement. Bereavement.

Question 29

What is the difference between horizontal and vertical equity?

Answer 29

Horizontal equity = Equal treatment for equal need e.g. individuals with pneumonia should all be treated equally Vertical equity = unequal treatment for unequal need e.g. patients with the cold and pneumonia should be treated differently

Question 30

What are the health care needs?

Answer 30

1. Felt need – individual perceptions of variation form normal health 2. Expressed need – individual seeks helps to overcome variation in normal health (demand) 3. Normative need – professional defines intervention appropriate for the expressed need 4. Comparative need – comparison between severity, range of interventions and cost

Question 31

What are the 3 approaches to health need assesments?

Answer 31

1. Epidemiological: 2. comparative 3. corporate

Question 32

What are maslows hierarchy of needs

Answer 32

Physiological – breathing, food, water, sleep. Safety – security of employment, resources, family health, property. Love/belonging – friendship, family, sexual intimacy. Esteem – self-esteem, confidence, achievement, respect. Self-actualisation – morality, creativity, spontaneity, problem solving, lack of prejudice, acceptable of facts.

Question 33

What are the 2 methods of evaluating health services?

Answer 33

1. Donabedian’s framework 2. Maxwells

Question 34

What is the donabedians framework?

Answer 34

1. Structure - what actually is the service e.g. how many heart surgeons there are 2. Process – how does the process work 3. Outcome – 5 Ds = death, disease, disability, discomfort, dissatisfaction

Question 35

What are the issues with health outcome?

Answer 35

1/ Link (cause + effect) between health service provided + health outcome may be difficult to establish as many other factors may be involved 2. Time lag between service provided + outcome may be long – E.g. healthy eating intervention in children + incidence of T2DM in adults. 3. Large sample sizes may be needed to detect statistically significant effects. 4. Data may not be available or there may be issues with data quality – Consider CART = Completeness, Accuracy, Relevance, Timeliness.

Question 36

What is the maxwells dimension of quality of care?

Answer 36

(3Es and 3As) - Effectiveness - Efficiency - Equity - Acceptability - Accessibility - Appropriateness

Question 37

What are the 3 NHS principles?

Answer 37

Universal – it meets the needs of everyone. Comprehensive – it’s based on clinical need, not ability to pay. Free – at the point of delivery.

Question 38

What is the assessment tool for domestic abuse?

Answer 38

DASH

Question 39

How do you handle domestic abuse?

Answer 39

1. Domestic abuse Multi-Agency Risk Assessment Conference (MARAC) 2. Independent Domestic Abuse Advisers (IDVAS) help victims to navigate the domestic abuse services