Public Health eBook Flashcards
There are many models of behaviour change. Those most relevant to public health are:
There are many models of behaviour change. Those most relevant to public health are:
• Health Belief Model
• Theories of Reasoned Action and Planned Behaviour
• Trans-theoretical (Stages of Change) Model
• COM-B Model
• Social Marketing
• ‘Nudge’ Theory
• 3 E’s Model
Health Belief Model
The HBM was proposed by Becker in 1974. The model was developed to explain why people would or would not participate in programmes for disease prevention or detection, and is based on two key ideas; threat appraisal and behavioural evaluation. The HBM is determined by:
• The severity of potential illness
• The individual’s perception of their personal likelihood of getting the illness
• The benefits of taking preventative steps
• The barriers to making change
As an example, the HBM can be applied to HIV; individuals are more likely to practice safer sex if they are aware that they are at risk of HIV infection through unprotected sex, the consequences of infection are serious, safer sex practices are effective at reducing risk and safer sex benefits outweigh barriers to, and costs of, condom use.
The key points of the Health Belief Model are:
• Self-efficacy is vital
• Confidence in achieving each small step
• Behaviour change will only occur if the individual sees the risks of the current behaviour as unacceptable and the new behaviour as having benefits
• The model fails to take into account the influence of family, friends or other role model
Theory of Planned Behaviour
The Theory of Planned Behaviour was proposed by Azjen and Fishbein in 1980, who suggested that understanding the individual’s intentions is the key to understanding
individual behaviour change. According to this theory there are three factors that affect the intention to behave, and that change needs to look at these factors; these factors are attitude, subjective norm and perceived behavioural control.
• Attitudes are determined by the belief that a desired outcome will occur if a particular behaviour is followed and that this outcome will be beneficial to health.
An example would be where people are more likely to exercise if they believe it will make them look and feel better
• Subjective norms look at a person’s beliefs about what others think they should do (known as normative beliefs) and their motivation to comply with the wishes of others. An example can be applied to smoking cessation as a smoker would be more likely to develop subjective norms to give up smoking if they believe that most people do not smoke and the people they value think it would be good for them to give up smoking
• Perceived behavioural control looks at an individual’s beliefs about their selfefficacy. This can be illustrated by a person living away from home for the first time being more likely to eat vegetables if they have a higher degree of perceived behavioural control, or confidence, in their ability to purchase and cook fresh food
Key points of the Theory of Planned Behaviour:
• Helps target information for interventions
• Can account for factors influencing people
• Relies on understanding a person’s beliefs about an issue, who that person sees as affecting these beliefs and what they see as the barriers to taking action
Attention should be paid to what Tones (1997) describes as the ‘pushes and pulls’ of competing motivations on intentions to act.
Trans-theoretical (Stages of Change) Model
The Trans-theoretical Model of Change was proposed by Prochanska and DiClemente (1984). The model was developed for application to addictive behaviour to explain how individuals move toward adopting healthy behaviours. According to the model, individuals may pass through 5 stages (pre-contemplation, contemplation, preparation, action and maintenance), which allows interventions to be targeted at each individual stage to
encourage change to occur. Table 1 illustrates the client characteristics and interventions relevant to each stage of the Trans-theoretical model for change.
Key points of the Trans-theoretical Model of Change:
• Relapse is part of the cycle
• People should move through each stage
• Re-entering the cycle a number of times before being successful is normal
• Applied in motivational interviewing and brief interventions e.g. smoking cessation
• Ethical concerns that application of the model leads to ‘categorisation’ (due to individuals being grouped in a particular stage)
• May exacerbate inequality of provision
COM-B Model
The COM-B model was proposed by Michie, van Stralen and West in 2011. The model proposes that there are three linked drivers behind behaviour, these being:
• Capability – psychological or physical ability to enact the behaviour
• Motivation – reflective and automatic mechanisms that activate or inhibit behaviour
• Opportunity – physical and social environment the enables the behaviour
The COM-B model links together all previous models of behaviour change in a new way, which forms the ‘Sources of Behaviour’ section of the Behaviour Change Wheel. This wheel has sources of behaviour at its core, with 9 interventions in the middle layer and the outer rim forming the policies to deliver the intervention.
Social Marketing
Social marketing is the process by which behaviour is influenced by the promotion of an idea within a society, and was proposed by Kotler and Zaltman (1971). This model of behaviour has a consumer orientation and requires an understanding of the interests and needs of the target audience. When using social marketing strategies it is important to use market research to ensure that the service or message you are conveying is acceptable to the target audience.
Social marketing assumes:
• The beliefs and attitudes of the individual will affect the impact of any communication
• Individuals are part of social systems – social norms influence the adoption of ideas and new behaviours
• Personal behaviour change is dependent on perception of the source of the message
– e.g. if the recipient does not trust the source they are less likely to change
• A health message needs to acknowledge the costs and benefits of making a change in behaviour
‘Nudge’ Theory
‘Nudge’ theory was proposed Thaler & Sunsten in their 2008 book ‘Nudge: Improving decisions about health, wealth and happiness’. ‘Nudge’ theory proposes that people will make choices that go against their best interests based on external influences, however it is
possible to steer (‘nudge’) people to positive behaviours. The theory has multiple applications including economics and health.
The Coalition Government of the time set up a ‘Behavioural Insights Team’, known as the ‘Nudge Unit’ to research the effects different approaches could have on changing behaviours.
The Nuffield Stewardship model – Ladder of interventions
This model shows the different approaches that can be adopted with interventions.
In Healthy Lives, Healthy People the UK Government set out its aim to “…use the least intrusive approach necessary to achieve the desired effect…” which links to the ladder of interventions as the least intrusive step that creates the desired outcome should be the approach adopted for the intervention.
3 E’s Model
The 3 E’s Model assumes that behaviour change is dependent on:
• Encouragement – motivation to change
• Empowerment – providing the information and support necessary to elicit change
• Environment – external influences on the individual
Models of Behaviour Key Points
Different models can be used to structure interventions
• All models deal with influences on an individual’s health related behaviour
• Behavioural techniques work but using threats does not
Overall behaviour change relies on characteristics of the patient, their surroundings and the information they are provided with. These include:
• Outcome expectancies (knowledge of health consequences)
• Personal relevance
• Positive attitude
• Self-efficacy – belief in their ability to change
• Descriptive norms – positive behaviours in other groups of people and particularly groups the individual aspires to be in
• Subjective norms – what the individual thinks others will think of them
• Personal norms – commitment to change
• Intention formation – goal setting
• Behavioural contracts – shared goals
• Relapse prevention
Health Inequalities (Social Influences on Health)
The National Institute for Clinical Excellence (NICE) define health inequalities as:
“…differences between people or groups due to social, geographical, biological or other factors. These differences have a huge impact, because they result in people who are worst off experiencing poorer health and shorter lives.”
According to the black report, explanations for inequalities include:
- Artefact – the effect is created by the measurement system used
- Natural or social selection – those who are healthier thrive and advance in society
- Cultural explanations – differing choices and preferences by social group
- Material explanation – poverty breeds ill health
- Social capital – social connections and interaction with local society determines health
The Biopsychosocial Model of Health
The Biopsychosocial model of health proposes that health and illness are seen as the combined product of:
• Biological characteristics – e.g. genetic predisposition
• Behavioural factors – e.g. lifestyle, stress, health beliefs
• Social conditions – e.g. cultural influences, family relationships and social support
This model suggests that health and illness are affected by a number of individual factors and wider social factors, the combination of which lead to health inequalities.
• According to the model the factors affecting health include motivation, emotions, stress, perception of illness, lifestyle, beliefs and work
• Social influences on health include wealth / poverty, education, social class, gender, mental health, ethnicity and race, and ageing
Dahlgren and Whitehead (1991) Main Determinants of Health
The Dahlgren and Whitehead Main Determinants of Health model illustrates the factors that determine health and can be used as the basis for policies to reduce health inequalities.
The model shows the different layers of health determinants; those towards the centre are less suitable targets for public health intervention, for example genetic factors are not something that could be influenced by a health campaign.
• Individual lifestyle factors include smoking, alcohol consumption, diet, physical activity and recreational drug use
• Social and community networks refers to family, friends and others within our social circles, and quality relationships with these groups are viewed as a ‘protective factor’ for health
• General socio-economic, cultural and environmental conditions look at other influences on health including wages, disposable income, availability of work, taxes,
and prices for essentials such as fuel, transport, food or clothing
Marmot and Shipley (1996)
Marmot and Shipley (1996) demonstrated a causal link between grade of employment and mortality in pre-retirement men, with this link declining in the 25 years following retirement.
Brief Advice and Brief Intervention Structure
The following should be covered:
• Assess commitment to change
• Explain risks of current behaviour and benefits of change
• Provide advice tailored to the person
• Supply self-help materials / resources
• Signpost to further or specialist information
• Offer follow up or ongoing support
