Behaviour change: general approaches

Resilience and coping: Antonovsky (1985, 1987) and Lazarus (1976, 1985; Lazarus and Folkman 1984)

Antonovsky argued that there are 'health-giving' or 'health-generating' factors in many situations. These 'salutogenic' factors can help people withstand or respond positively to stressors, crises or difficulties. They help to protect against vulnerability and disease and may help maintain good mental and physical health. Lazarus argued that people develop habitual ways of coping with life. However, although they may be highly effective from the individual's point of view, some coping mechanisms (like smoking or excessive alcohol consumption) may damage their health and the health of others. Behaviour change and readiness to change behaviour takes place in this context.

'Habitus': Bourdieu (1977)

Bourdieu argued that many of the things that people do and believe are so familiar and habitual that they go largely unnoticed (because they are part of their 'habitus'). This makes changing them very difficult.

Social capital (Bourdieu 1986; Putnam 2000; Morgan and Swann 2004)

Social capital is commonly defined as those features of a society, such as networks, social trust and cohesion, which facilitate cooperation among people for mutual benefit. It was of interest because of the way these factors might influence health behaviours and people's ability to change.

Society: Giddens (1979, 1982, 1984)

Giddens argued that society was the product of interaction between individual human behaviour and the social structure. He argued that the human actions or agency produce societal patterns. The patterns repeat themselves to such a degree that structures emerge. Although those structures change, sometimes gradually, sometimes rapidly, individuals are aware of them and orient their actions in line with them (and are constrained by them).

The Theory of Planned Behaviour: (Ajzen 1991) and Bandura's construct of self-efficacy (1997)

The Theory of Planned Behaviour (TPB) is the most widely applied model of beliefs, attitudes and intentions that precede action (Ajzen 2001; Conner and Sparks 2005). TPB proposes that intention is the main determinant of action and is predicted by attitude, subjective norms and perceived behavioural control (PBC). PBC is a person's perception of whether or not they can control their actions and is closely related to Bandura's construct of self-efficacy (1997). Both PBC and self-efficacy are likely to bolster intentions and sustain action because people are more likely to attempt actions that are controllable and easy to perform.

Phase 1: comparing the cost-effectiveness of behaviour change strategies to reduce the risk of CHD

Many interventions aimed at tackling multiple risk factors fell into the 'likely to be very cost effective' category (£0 to £20,000/per cost per quality adjusted life year [QALY]). These included a mix of population-level and individual interventions for adults over the age of 30.

Interventions aimed at changing the behaviour of adults with specific CHD risk factors (such as smoking, poor diet and low levels of physical activity) fell into the 'likely to be very cost effective' category. Two non-advisory interventions (labelling of foods containing trans-fatty acid and a population-based programme promoting a healthier diet) also fell into the 'likely to be very cost effective' group.

Significant gaps in the evidence were noted. There was little evidence on the cost-effectiveness of using behaviour change interventions with specified sub-groups (for example, 19- to 30-year-olds, low-income groups, pregnant women, and particular ethnic or disadvantaged groups). The quality of evidence was also a cause for concern. For example, there was a lack of reliable data from which to extrapolate the long-term health outcomes. In addition, only a limited number of economic evaluations had been conducted alongside RCTs of behaviour change interventions to reduce CHD.

Phase 2: modelling

In the second phase, a deterministic Markov chain simulation model was developed of a population-wide intervention to lower cholesterol and prevent CHD. The intervention was carried out in Norway in 1990. It included a mass media campaign and information delivered to a range of sectors including academia, the agricultural sector and schools. The model extrapolated the results to England and Wales in the first decade of 2000.

In the base case, an incremental cost-effectiveness ratio (ICER) of £87 per QALY (£116 per life year) was estimated. However, it was noted that the health benefits were underestimated, as this model only reported those related to CHD. Sensitivity analysis estimated that the intervention would be highly cost effective in a wide range of situations.