Air quality: key behaviours report

8 Conclusions

8.1 Key behaviours impacting on air quality

This rapid evidence review aimed to provide evidence on the key behaviours that impact on air quality to inform future public engagement. Specifically, we sought to identify the behaviours that have the greatest impact on improving air quality, and assess the motivations and barriers associated with these behaviours in relation to the COM-B framework for behaviour change.

The review highlighted that, of the large body of literature on air quality issues, very little frames air quality specifically in behavioural terms. We found no review papers evaluating the relative impacts of different behaviours across the spectrum of behaviours relevant to air quality. As highlighted in section 3, quantifying and comparing the impacts of different behaviours is challenging for a range of reasons. As a result, we were not able to draw direct conclusions about the relative impact of different behaviours that would allow us to prioritise behaviours. We were, however, able to synthesise a set of eight key behaviours for air quality improvement that are supported by evidence. These behaviours centre around the areas of reducing car use, switching vehicle, driving differently and heating the home differently.

8.2 Use of the COM-B to underpin design of policy interventions

Our high-level analysis of the factors influencing the key behaviours using the COM-B framework highlights the wide range of motivations and barriers at play. It is essential that the design of interventions for behaviour change take into consideration the full range of factors influencing behaviour. The COM-B model highlights that increasing motivations to perform a behaviour will not result in behaviour change in the absence of supporting conditions that foster opportunity (such as supporting infrastructure and social norms) as well as individuals' capability. Behaviour change interventions often focus solely on persuasive communications (targeting motivation) or raising awareness, both of which are limited in their effectiveness when employed alone (Whitmarsh et al., 2021). Part of this is a result of the conceptual models that we use (explicitly or implicitly) to understand behaviour, with models such as the knowledge-deficit model and psychological models of motivation having had enduring influence on intervention design. Integrative models such as the COM-B (and the Scottish Government's Individual-Social-Material, ISM, framework) offer promise in that they can help to underpin the design of more effective combinations of interventions that can create the necessary conditions for behaviour change.

The COM-B framework may also help to tackle perceptions that policy focusing on behaviour change seeks to shift responsibility for change onto individuals and away from government and institutions. In highlighting the importance of capability and opportunity as well as motivation, it prompts intervention designers to consider possibilities for intervention at different points in a system, engaging actors from across society in delivering change.