ASBHDS Session 5 - Health Promotion, Screening and Risk Communication

Question 1

What are determinants of health?

Answer 1

A range of factors that have a powerful and cumulative effect on the health of populations, communities and individuals:

• The physical environment,
• The social and economic environment,
• Our individual genetics, characteristics and behaviours

Question 2

What realisation arises from the understanding of health determinants?

Answer 2

“The context of people’s lives determine their health, and so blaming individuals for having poor health or crediting them for good health is inappropriate. Individuals are unlikely to be able to directly control many of the determinants of health.”

Question 3

Outline the health career.

Answer 3

Question 4

Define health promotion.

Answer 4

• The process of enabling people to increase control over and to improve their health.
• Health is a positive concept emphasizing social and personal resources, as well as physical capacities.
• Therefore, health promotion is not just the responsibility of the health sector, but goes beyond healthy lifestyles to well-being.

Question 5

Identify and describe the principles of health promotion.

Answer 5

• Empowering: Enabling individuals and communities to assume more power over the determinants of health

- Participatory: Involving all concerned at all stages of the process

- Holistic: Fostering physical, mental, social and spiritual health

- Intersectoral: Involving the collaboration of agencies from relevant sectors

- Equitable: Guided by a concern for equity and social justice

- Sustainable: Bringing about changes that individuals and communities can maintain once funding has ended

- Multi-strategy: Uses a variety of approaches – including policy development, organisational change, community development, legislation

Question 6

What is the relationship with health promotion and public health?

Answer 6

• Public Health has tended to place more emphasis on ends.
• Health Promotion has placed more value on means of achieving those.
• Public Health = health protection + health promotion?
• Health Promotion = health education x healthy public policy

Question 7

In terms of critiques, outline the sociological perspectives of health promotion.

Answer 7

• Structural critiques

I. Material conditions that give rise to ill health marginalized

II. Focus on individual responsibility

• Surveillance critiques – Monitoring and regulating population
• Consumption critiques – Lifestyle choices not just seen as health ‘risks’ but also tied up with identity construction

Question 8

Identify the 5 approaches of health promotion in action.

Answer 8

• Medical or preventive
• Behaviour change
• Educational
• Empowerment
• Social change

Question 9

What is the aim and 4 main approaches of primary prevention?

Answer 9

• Aim: to prevent the onset of disease or injury - by reducing exposure to risk factors
• 4 main approaches:

I. Immunisation (e.g. measles, TB…)

II. Prevention of contact with environmental risk factors (e.g. asbestos)

III. Taking appropriate precautions re communicable disease

IV. Reducing risk factors from health-related behaviours (e.g. quitting smoking)

Question 10

Outline the aim of secondary prevention and provide some examples.

Answer 10

• Aim: to detect and treat a disease (or its risk factors) at an early stage (to prevent progression / potential future complications and disabilities from the disease)
• Examples:

I. Screening for cervical cancer

II. Monitoring and treating blood pressure

III. Screening for glaucoma

Question 11

Outline the aims of tertiary prevention and provide some examples.

Answer 11

• Aims to minimise the effects of established disease
• Examples:

I. To maximise the remaining capabilities and functions of an already disabled patient

II. Renal transplants (to prevent someone dying of renal failure)

III. Steroids for asthma (to prevent asthma attacks)

Question 12

Illustrate some of the dilemmas raised by health promotion:

Dilemma I: Ethics of interfering in people’s lives

Answer 12

• Potential psychological impact of health promotion messages
• State interventions in individuals’ lives

I. “Nanny state”

II. “Liberal do-gooders”

III. Rights and choices

Question 13

Illustrate some of the dilemmas raised by health promotion:

Dilemma II: Victim blaming

Answer 13

• Focusing on individual behavioural change plays down the impact of wider socioeconomic & environmental determinants of health
• Examples:

I. Housing conditions, water and air quality, workplace conditions, roads, green spaces…

II. High perceived costs of ‘healthy living’

Question 14

Illustrate some of the dilemmas raised by health promotion:

Dilemma III: ‘Fallacy of empowerment”

Answer 14

• Does giving people the information give them the power? No
• ‘Unhealthy’ lifestyles are not due to ignorance but due to adverse circumstances and wider socio-economic determinants of health.

Question 15

Illustrate some of the dilemmas raised by health promotion:

Dilemma IV: Reinforcing of negative stereotypes

Answer 15

• Health promotion messages have the potential to reinforce negative stereotypes associated with a condition or group
• Example: – Leaflets aimed at HIV prevention in drug users can reinforce that drug users only have themselves to blame for their situation.

Question 16

Illustrate some of the dilemmas raised by health promotion:

Dilemma V: Unequal distribution of responsibility

Answer 16

• Implementing healthy behaviours in the family is often left up to women.
• Example: Healthy eating advice and the responsibility / ‘unenviable’ task to get their family to eat more fresh fruit, less processed food, etc.

Question 17

Illustrate some of the dilemmas raised by health promotion:

Dilemma VI: Prevention paradox

Answer 17

Interventions that make a difference at population level might not have much effect on the individual.

Question 18

Explain the relevance of lay beliefs to health promotion interventions.

Answer 18

• Link with lay beliefs

I. If people don’t see themselves as a ‘candidate’ for a disease they may not take on board the health promotion messages.

II. Awareness of anomalies and randomness of a disease (e.g. heart attacks) will also impact on views about candidacy

• Importance of health promoters engaging with lay beliefs
• Awareness of anomalies and randomness

Question 19

What is evaluation?

Answer 19

“The rigorous & systematic collection of data to assess the effectiveness of a programme in achieving predetermined objectives.”

Question 20

Why should one evaluate?

Answer 20

• Need for evidence-based interventions: Properly conducted evaluation studies can provide necessary evidence.

- Accountability: Evidence also gives legitimacy to interventions and political support.

- Ethical obligation: The imperative to ensure there is no direct or indirect harm

- Programme management and development

Question 21

What are the types of health promotion evaluation?

Answer 21

• Process
• Impact
• Outcome

Question 22

Describe process evaluation.

Answer 22

• Focuses on assessing the process of programme implementation.
• Also, referred to as ‘formative’ or ‘illuminative’ evaluation.
• Employs a wide range of mainly qualitative methods.

Question 23

Describe impact evaluation.

Answer 23

• Assesses the immediate effects of the intervention.
• Tends to be the more popular choice, as it is the easiest to do.

Question 24

Describe outcome evaluation.

Answer 24

• Measures more long-term consequences.
• Measures what is achieved: – For example: improvement in clients’ lives; reduction of symptoms; level of harm reduction.
• Timing of evaluation can influence ‘outcome’:

I. Delay: some interventions might take a long time to have an effect;

II. Decay: some interventions wear off rapidly

Question 25

What are the difficulties with evaluation?

Answer 25

Demonstrating an attributable effect is difficult because:

• Design of the intervention
• Possible lag time to effect
• Many potential intervening or concurrent confounding factors
• High cost of evaluation research - studies are likely to be large scale and long term

Question 26

How does one detect disease?

Answer 26

• Spontaneous presentation
• Opportunistic case finding
• Screening

Question 27

Outline spontaneous presentation.

Answer 27

• Person presents with symptoms
• Self-defined as a ‘patient’
• Service - GP and A&E / Other services
• A diagnosis is made

Question 28

Define diagnosis.

Answer 28

The definitive identification of a suspected disease or defect by application of tests, examinations or other procedures (which can be extensive) to definitely label people as either having a disease or not having a disease

Question 29

Outline diagnosis.

Answer 29

• The diagnosis is made following tests
• Treatment will follow
• The ‘patient’ will be prepared to accept the (reasonable) risks (sideeffects) associated with the treatment in order to get well

Question 30

Define screening.

Answer 30

A systematic attempt to detect an unrecognised condition by the application of tests, examinations, or other procedures, which can be applied rapidly (and cheaply) to distinguish between apparently well persons who probably have a disease (or its precursor) and those who probably do not

Question 31

Outline the screening process.

Answer 31

Screening is the process of identifying healthy people who may be at increased risk of disease or condition. The screening provider then offers information, further tests and treatment. This is to reduce associated risks or complications.

Question 32

What is the purpose of screening?

Answer 32

• To give a better outcome compared with finding something in the usual way (having symptoms and selfreporting to health services)
• If treatment can wait until there are symptoms, there is no point in screening
• Finding something earlier is not the primary objective

Question 33

List the criteria for implementing a screening programme, including those relating to the condition, the test, the treatment, and the programme

Answer 33

Five areas of criteria:

• Condition
• Test
• Intervention
• Screening programme
• Implementation

Question 34

Outline the condition area.

Answer 34

• An important health problem (frequency/severity) with epidemiology, incidence, prevalence and natural history understood
• All the cost-effective primary prevention interventions should have been implemented as far as practicable
• If the carriers of a mutation are identified as a result of screening the natural history of people with this status should be understood, including the psychological implications

Question 35

What are the properties of the test area.

Answer 35

• Simple, safe, precise and validated screening test
• Distribution of test values in the population must be known and an agreed cut-off level must be defined and agreed
• Acceptable to target population
• Agreed policy on further diagnostic investigation of those who test positive and choices available to them
• If the test is for a particular mutation or set of genetic variants the method for their selection and the means through which these will be kept under review in the programme should be clearly set out

Question 36

What are the two types of error that any screening test will make?

Answer 36

• False positive – It is going to refer well people for further investigation. Putting them through stress, anxiety and inconvenience. There will be direct costs and opportunity costs.

- False negative – It is going to fail to refer people who do actually have an early form of the disease. This results in inappropriate reassurance and will possibly delay presentation with symptoms.

Question 37

What are the features of test validity?

Answer 37

• Sensitivity (detection rate)
• Specificity
• Positive predictive value
• Negative predictive value

Question 38

Outline the sensitivity of the test.

Answer 38

• Is the proportion of the people with the disease who are test positive
• Also known as the detection rate
• The proportion of the people who really have the disease who are identified correctly by the test as having the disease
• Sensitivity is the probability a case will test positive
• If the sensitivity is high then the test is very good at correctly identifying people with the disease you are screening for
• A high sensitivity is ideal (although not always possible)

Question 39

Outline the specificity of the test.

Answer 39

• Is the proportion of the people without the disease who are test negative
• The proportion of the people who really do not have the disease who are identified correctly by the test as not having the disease
• Probability a non-case will test negative
• If the specificity is high then the test is very good at correctly identifying people without the disease as not having the disease
• A high specificity is ideal (although not always possible)

Question 40

What are the features of sensitivity and specificity?

Answer 40

• Sensitivity and specificity are a function of the characteristics of the test
• When the same test is applied in the same way in different populations the test will have the same sensitivity and specificity

Question 41

Briefly, outline positive predictive value.

Answer 41

• This is what people want to know:
• “If I am test positive – what is my risk of actually having the disease?”*
• In fact, many people assume incorrectly that because they test positive they must have the disease
• Probability that someone who has tested positive actually has the disease
• This value is strongly influenced by the prevalence of the disease

Question 42

In terms of PPV, describe the influence of prevalence for a high prevalence disease,

Answer 42

Assume the following scenario:

1. Screening in a diabetic clinic for diabetic retinopathy
2. Diabetic retinopathy occurs commonly in diabetics and thus is a high prevalence condition in diabetic clinic populations
3. Assume the prevalence of diabetic retinopathy is 30%…

Question 43

In terms of PPV, describe the influence of prevalence for a low prevalence disease.

Answer 43

Assume the following scenario:

1. Now we are going to take the same test (same sensitivity and specificity) for diabetic retinopathy and screen the general population – where of course the condition is much less common (low prevalence)
2. Assume the prevalence is 1%…

Question 44

Outline Negative predictive value.

Answer 44

• NPV - is the proportion of the people who are test negative who actually do not have the disease
• The NPV is the answer to the question
• “If the screening test is negative – what are the chances that I really don’t have the disease?”*

Question 45

Outline the intervention area.

Answer 45

• Effective intervention for patients identified through screening, with evidence that intervention at a presymptomatic phase leads to better outcomes for the screened individual compared with usual care.
• There should be agreed evidence based policies covering which individuals should be offered interventions and the appropriate intervention to be offered.

Question 46

Outline the screening programme area.

Answer 46

• Proven effectiveness in reducing mortality or morbidity (high quality RCT data)
• Evidence that the complete screening programme is clinically, socially and ethically acceptable to health professionals and public
• Benefit gained by individuals should outweigh any harms for example from overdiagnosis, overtreatment, false positives, false reassurance, uncertain findings and complications
• Opportunity cost of the screening programme should be economically balanced in relation to expenditure on medical care as a whole

Question 47

Outline the implementation area,

Answer 47

• Clinical management and patient outcomes should be optimised in all healthcare providers
• All other options for managing the condition should have been considered
• Management and monitoring programme – quality assurance
• Adequate staffing and facilities for programme
• Evidence-based information available to potential participants (informed choice)
• Public pressure should be anticipated - decisions should be scientifically justifiable to the public

Question 48

List the advantages of screening for a disease.

Answer 48

• Screening makes it possible to detect many diseases at birth, with no risk to the child.
• Treatment that begins prior to the appearance of symptoms makes it possible to avoid serious and permanent consequences for the child. For many diseases, early treatment can even enable completely normal development of the child.
• In general, a single blood specimen and a single urine specimen will suffice to detect all the target diseases.

Question 49

Outline the disadvantages of screening for disease.

Answer 49

• Occasionally, specimens may need to be taken a second time.
• If you receive a call due to an abnormal test result for your child, it is possible that the period of time needed to confirm the disease may take several months. This could be because the variant of the disease is rare or more difficult to diagnose, and naturally, this could be a source of concern for the parents.
• Even if treatment begins at an early age, complications of the disease could still arise.
• Despite its high efficacy, screening does have limits. For example, there exists a small chance that your child does have a target disease that went undetected during the screening process.

Question 50

Describe difficulties of evaluating the effectiveness of screening programmes.

Evaluating difficulty 1: Lead time bias

Answer 50

Evaluating difficulty 1: Lead time bias

• Early diagnosis falsely appears to prolong survival
• Screened patients appear to survive longer, but only because they were diagnosed earlier
• Patients live the same length of time, but longer knowing they have the disease

Question 51

Describe difficulties of evaluating the effectiveness of screening programmes.

Evaluating difficulty 2: Length time bias

Answer 51

Evaluation difficulty 2: Length time bias

• Screening programmes better at picking up slow growing, unthreatening cases than aggressive, fast-growing ones
• Diseases that are detectable through screening are more likely to have a favourable prognosis, and may indeed never have caused a problem
• Could lead to false conclusion that screening is beneficial in lengthening the lives of those found positive – curing people that didn’t need curing?

Question 52

Describe difficulties of evaluating the effectiveness of screening programmes.

Evaluating difficulty 3: Selection bias

Answer 52

• Studies of screening often skewed by ‘healthy volunteer’ effect
• Those who have regular screening likely to also do other things that protect them from disease
• An RCT would help deal with this bias

Question 53

Outline the need for an informed choice.

Answer 53

• Need an informed choice – Increasing emphasis on promoting informed choice about screening. But is this happening?

- Difficulty achieving informed choice – Communicating benefits, harms and risks of preventive interventions can be challenging

Question 54

Offer a critical perspective on screening programmes.

Answer 54

• Is the natural history always understood?
• How many abnormalities would regress spontaneously or never be problematic?
• Are the ‘right’ people being screened?
• Has screening caused any observed reduction in mortality?
• Over-diagnosis and over-treatment?
• Psychological impact?

Question 55

Give examples of screening programmes in the UK.

Answer 55

• NHS breast screening (BSP) programme
• NHS cervical screening (CSP) programme
• NHS diabetic eye screening (DES) programme
• NHS newborn hearing screening programme (NHSP)
• NHS sickle cell and thalassaemia (SCT) screening programme

Question 56

Explain sociological critiques of health promotion and screening

Answer 56

• Victim blaming / Individualising pathology
• Individuals and populations increasingly subject to surveillance – prevention as social control?
• Moral obligation
• Feminist critiques