Health and life

However, several studies have reported conflicting findings. Janz and Becker (1984) found that healthy behavioural intentions are related to low perceived severity, not high as predicted, and several studies have suggested an association between low susceptibility (not high) and healthy behaviour (Becker et al. 1975; Langlie 1977). Hill et al. (1985) applied the HBM to cervical cancer, to examine which factors predicted cervical screening behaviour. The results suggested that barriers to action was the best predictor of behavioural intentions and that perceived susceptibility to cervical cancer was also significantly related to screening behaviour. However, benefits and perceived severity were not related. Janz and Becker (1984) carried out a study using the HBM and found that the best predictors of health behaviour are perceived barriers and perceived susceptibility to illness. However, Becker and Rosenstock (1984), in a review of 19 studies using a meta-analysis that included measures of the HBM to predict compliance, calculated that the best predictors of compliance are the costs and benefits and the perceived severity.

The transtheoretical model of behaviour change was originally developed by Prochaska and DiClemente (1982) as a synthesis of 18 therapies describing the processes involved in eliciting and maintaining change. It is now more commonly known as the stages-of-change model. Prochaska and DiClemente examined these different therapeutic approaches for common processes and suggested a new model of behaviour change based on the following stages:
1 Pre-contemplation: not intending to make any changes.
2 Contemplation: considering a change.
3 Preparation: making small changes.
4 Action: actively engaging in a new behaviour.
5 Maintenance: sustaining the change over time.
These stages, however, do not always occur in a linear fashion (simply moving from 1 to 5) but the theory describes behaviour change as dynamic and not ‘all or nothing’. For example, an individual may move to the preparation stage and then back to the contemplation stage several times before progressing to the action stage. Furthermore, even when an individual has reached the maintenance stage, they may slip back to the contemplation stage over time.
The model also examines how the individual weighs up the costs and benefits of a particular behaviour. In particular, its authors argue that individuals at different stages of change will differentially focus on either the costs of a behaviour (e.g. stopping smoking will make me anxious in company) or the benefits of the behaviour (e.g. stopping smoking will improve my health).
For example, a smoker at the action (I have stopped smoking) and the maintenance (for four months) stages tend to focus on the favourable and positive feature of their behaviour (I feel healthier because I have stopped smoking), whereas smokers in the pre-contemplation stage tend to focus on the negative features of the behaviour (it will make me anxious).
The stages-of-change model has been applied to several health-related behaviours, such as smoking, alcohol use, exercise and screening behaviour (e.g. DiClemente et al. 1991; Marcus et al. 1992). If applied to smoking cessation, the model would suggest the following set of beliefs and behaviours at the different stages:
1 Pre-contemplation: ‘I am happy being a smoker and intend to continue smoking’.
2 Contemplation: ‘I have been coughing a lot recently, perhaps I should think about stop- ping smoking’.
3 Preparation: ‘I will stop going to the pub and will buy lower tar cigarettes’.
4 Action: ‘I have stopped smoking’.
5 Maintenance: ‘I have stopped smoking for four months now’.
This individual, however, may well move back at times to believing that they will continue to smoke and may relapse (called the revolving door schema).
The stages-of-change model is increasingly used both in research and as a basis to develop interventions that are tailored to the particular stage of the specific person concerned. For example, a smoker who has been identified as being at the preparation stage would receive a different intervention to one who was at the contemplation stage. However, the model has recently been criticized for the following reasons (Weinstein et al. 1998; Sutton 2000, 2002a; West 2006):
■ It is difficult to determine whether behaviour change occurs according to stages or along a continuum. Researchers describe the difference between linear patterns between stages which are not consistent with a stage model and discontinuity patterns which are consistent.
■ However, the absence of qualitative differences between stages could either be due to the absence of stages or because the stages have not been correctly assessed and identified.
■ Changes between stages may happen so quickly as to make the stages unimportant.
■ Interventions that have been based on the stages-of-change model may work because the individual believes that they are receiving special attention, rather than because of the effectiveness of the model per se.
■ Most studies based on the stages-of-change model use cross-sectional designs to examine differences between different people at different stages of change. Such designs do not allow conclusions to be drawn about the role of different causal factors at the different stages (i.e. people at the preparation stage are driven forward by different factors than those at the contemplation stage). Experimental and longitudinal studies are needed for any conclusions about causality to be valid.
■ The concept of a ‘stage’ is not a simple one as it includes many variables: current behavi- our, quit attempts, intention to change and time since quitting. Perhaps these variables should be measured separately.
■ The model focuses on conscious decision-making and planning processes. Further it assumes that people make coherent and stable plans.
■ Using the model may be no better than simply asking people, ‘Do you have any plans to try to…?’ or ‘Do you want to…?’.

If applied to a health-related behaviour such as screening for cervical cancer, the HBM predicts regular screening for cervical cancer if an individual perceives that she is highly susceptible to cancer of the cervix, that cervical cancer is a severe health threat, that the benefits of regular screening are high, and that the costs of such action are comparatively low. This will also be true if she is subjected to cues to action that are external, such as a leaflet in the doctor’s waiting room, or internal, such as a symptom perceived to be related to cervical cancer (whether correct or not), such as pain or irritation. When using the new amended HBM, the model would also predict that a woman would attend for screening if she is confident that she can do so and if she is motivated to maintain her health.

The HBM predicts that behaviour is a result of a set of core beliefs, which have been redefined over the years. The original core beliefs are the individual’s perception of:
■ susceptibility to illness (e.g. ‘my chances of getting lung cancer are high’)
■ the severity of the illness (e.g. ‘lung cancer is a serious illness’)
■ the costs involved in carrying out the behaviour (e.g. ‘stopping smoking will make me irritable’)
■ the benefits involved in carrying out the behaviour (e.g. ‘stopping smoking will save me money’)
■ cues to action, which may be internal (e.g. the symptom of breathlessness), or external (e.g. information in the form of health education leaflets).
The HBM suggests that these core beliefs should be used to predict the likelihood that a behaviour will occur. In response to criticisms the HBM has been revised originally to add the construct ‘health motivation’ to reflect an individual’s readiness to be concerned about health matters (e.g. ‘I am concerned that smoking might damage my health’). More recently, Becker and Rosenstock (1987) have also suggested that perceived control (e.g. ‘I am confident that I can stop smoking’) should be added to the model.

The health belief model (HBM) was developed initially by Rosenstock (1966) and further by Becker and colleagues throughout the 1970s and 1980s in order to predict preventive health behaviours and also the behavioural response to treatment in acutely and chronically ill patients. However, over recent years, the health belief model has been used to predict a wide variety of health-related behaviours.

Several studies support the predictions of the HBM. Research indicates that dietary compliance, safe sex, having vaccinations, making regular dental visits and taking part in regular exercise programmes are related to the individual’s perception of susceptibility to the related health problem, to their belief that the problem is severe and their perception that the benefits of preventive action outweigh the costs (e.g. Becker 1974; Becker et al. 1977; Becker and Rosenstock 1984).
Research also provides support for individual components of the model. Norman and Fitter (1989) examined health screening behaviour and found that perceived barriers are the greatest predictors of clinic attendance. Several studies have examined breast self-examination behaviour and report that barriers (Lashley 1987; Wyper 1990) and perceived susceptibility (Wyper 1990) are the best predictors of healthy behaviour.
Research has also provided support for the role of cues to action in predicting health behaviours, in particular external cues such as informational input. In fact, health promotion uses such informational input to change beliefs and consequently promote future healthy behaviour. Information in the form of fear-arousing warnings may change attitudes and health behaviour in such areas as dental health, safe driving and smoking (e.g. Sutton 1982; Sutton and Hallett 1989). General information regarding the negative consequences of a behaviour is also used both in the prevention and cessation of smoking behaviour (e.g. Sutton 1982; Flay 1985). Health information aims to increase knowledge and several studies report a significant relationship between illness knowledge and preventive health behaviour. Rimer et al. (1991) report that knowledge about breast cancer is related to having regular mammograms. Several studies have also indicated a positive correlation between knowledge about breast self-examination (BSE) and breast cancer and performing BSE (Alagna and Reddy 1984; Lashley 1987; Champion 1990). One study manipulated knowledge about pap tests for cervical cancer by showing subjects an informative videotape and reported that the resulting increased knowledge was related to future healthy behaviour (O’Brien and Lee 1990).

Central to unrealistic optimism is the notion of risk perception and the proposal that individuals can process risk information in ways that enables them to continue their unhealthy behaviour. In fact research suggests that those least persuaded by risk data are often those most at risk (Sherman et al. 2000). An example of this is smokers’ ability to continue to smoke even when the words ‘smoking kills’ are written on their packet of cigarettes. Recently, however, it has been suggested that self-affirmation may help reduce the tendency to resist threat information. Self-affirmation theory suggests that people are motivated to protect their sense of self-integrity and their sense of themselves as being ‘adaptively and morally adequate’ (Steele 1988). Therefore if presented with information that threatens their sense of self, they behave defensively. However, if given the opportunity to self-affirm in another domain of their lives, then their need to become defensive is reduced. For example, if a smoker thinks that they are a sensible person, when confronted with a message that says that smoking is not sensible their integrity is threatened and they behave defensively by blocking the information. If given the chance, however, to think about another area in which they are sensible then they are less likely to become defensive about the anti-smoking message. A couple of recent studies have tested the impact of self-affirmation on the processing of information about the link between alcohol and breast cancer in young women and smoking in young smokers (Harris and Napper 2005; Harris et al. 2006). In the first study, young women who were drinking above the recommended limit were randomized either to the self-affirmation condition or the control condition (Harris and Napper 2005). Those in the self-affirmation condition were asked to write about their most important value and why it was important to them. All were then given a health message about the links between excessive alcohol intake and breast cancer. The results showed that those who had self-affirmed were more accepting of the health message. In a similar study, smokers were asked to study four images depicting the dangers of smoking and half underwent a self-affirmation task. These results also showed that those who had self-affirmed rated the images as more threatening and reported higher levels of self-efficacy and intentions to stop smoking (Harris et al. 2006). Therefore it would seem that although people can deny and block the risks associated with their behaviour, this defensive process is reduced if they are encouraged to self-affirm. This approach has implications for a wide range of health-related behaviours and the development of more effective interventions to change behaviour.

Weinstein (1983, 1984) suggested that one of the reasons that people continue to practise unhealthy behaviours is due to inaccurate perceptions of risk and susceptibility – their unrealistic optimism. He asked subjects to examine a list of health problems and to state ‘compared to other people of your age and sex, what are your chances of getting [the problem] – greater than, about the same, or less than theirs?’ The results of the study showed that most subjects believed that they were less likely to get the health problem. Weinstein called this phenomenon unrealistic optimismas he argued that not everyone can be less likely to contract an illness. Weinstein (1987) described four cognitive factors that contribute to unrealistic optimism: (1) lack of personal experience with the problem; (2) the belief that the problem is preventable by individual action; (3) the belief that if the problem has not yet appeared, it will not appear in the future; and (4) the belief that the problem is infrequent. These factors suggest that perception of own risk is not a rational process.
In an attempt to explain why individuals’ assessment of their risk may go wrong, and why people are unrealistically optimistic, Weinstein (1983) argued that individuals show selective focus. He claimed that individuals ignore their own risk-increasing behaviour (‘I may not always practise safe sex but that’s not important’) and focus primarily on their risk-reducing behaviour (‘but at least I don’t inject drugs’). He also argues that this selectivity is compounded by egocentrism: individuals tend to ignore others’ risk-decreasing behaviour (‘my friends all practise safe sex but that’s irrelevant’). Therefore an individual may be unrealistically optimistic if they focus on the times they use condoms when assessing their own risk and ignore the times they do not and, in addition, focus on the times that others around them do not practise safe sex and ignore the times that they do.
In one study, subjects were required to focus on either their risk-increasing (‘unsafe sex’) or their risk-decreasing behaviour (‘safe sex’). The effect of this on their unrealistic optimism for risk of HIV was examined (Hoppe and Ogden 1996). Heterosexual subjects were asked to complete a questionnaire concerning their beliefs about HIV and their sexual behaviour. Subjects were allocated to either the risk-increasing or risk-decreasing condition. Subjects in the risk-increasing condition were asked to complete questions such as ‘since being sexually active how often have you asked about your partners’ HIV status?’ It was assumed that only a few subjects would be able to answer that they had done this frequently, thus making them feel more at risk. Subjects in the risk-decreasing condition were asked questions such as ‘since being sexually active how often have you tried to select your partners carefully?’ It was believed that most subjects would answer that they did this, making them feel less at risk. The results showed that focusing on risk-decreasing factors increased optimism by increasing perceptions of others’ risk. Therefore, by encouraging the subjects to focus on their own healthy behaviour (‘I select my partners carefully’), they felt more unrealistically optimistic and rated themselves as less at risk compared with those who they perceived as being more at risk.

The internal versus external dimension of attribution theory has been specifically applied to health in terms of the concept of a health locus of control. Individuals differ as to whether they tend to regard events as controllable by them (an internal locus of control) or uncontrollable by them (an external locus of control). Wallston and Wallston (1982) developed a measure of the health locus of control which evaluates whether an individual regards their health as controllable by them (e.g. ‘I am directly responsible for my health’), whether they believe their health is not controllable by them and in the hands of fate (e.g. ‘whether I am well or not is a matter of luck’), or whether they regard their health as under the control of powerful others (e.g. ‘I can only do what my doctor tells me to do’). Health locus of control has been shown to be related to whether an individual changes their behaviour (e.g. gives up smoking) and to the kind of communication style they require from health professionals. For example, if a doctor encourages an individual who is generally external to change their lifestyle, the individual is unlikely to comply if they do not deem themselves responsible for their health.
Although the concept of a health locus of control is intuitively interesting, there are several problems with it:
■ Is the health locus of control a state or a trait? (Am I always internal?)
■ Is it possible to be both external and internal?
■ Is going to the doctor for help external (the doctor is a powerful other who can make me well) or internal (I am determining my health status by searching out appropriate intervention)?