Designing a behaviour change intervention to address the behavioural risk factors for stillbirth: A study protocol

Introduction

Stillbirth is one of the most devastating outcomes that a woman and her family can experience¹. Although not all, some cases of stillbirth are preventable, and hence, efforts are being conducted internationally to tackle the risk factors for stillbirth in order to reduce its rates². Some of the modifiable risk factors for stillbirth include a behavioural component, meaning that they have the potential to be modified through behaviour change interventions. These risk factors are substance use (smoking^3–6, alcohol consumption^7,8, illicit drug use⁶), high maternal weight^9–11, lack of attendance to antenatal care¹², and sleep position^13,14. Although some interventions tackling the behavioural risk factors for stillbirth already exist^15–17, none of them have been designed to take into consideration all the different behavioural risk factors and the particularities regarding risk perception in the context of pregnancy and stillbirth, and with a behaviour change theory basis.

Behavioural theories are the accumulated knowledge of the assumptions of what behaviour is, how is it influenced, and what mechanisms of action will produce a change in behaviour¹⁸. Behavioural theories are important because they can help explain and facilitate understanding of the factors that influence behaviour, and through which mechanisms this behaviour is influenced¹⁹. Despite the importance and usefulness of behavioural theory, many behaviour change interventions have been designed without evidence or with a poor application of theory²⁰. Mitchie et al. (2011) hypothesise that this is because the existing frameworks to date did not meet intervention designer’s needs, as they either contained poorly defined constructs or did not produce enough level of detail to address what is effective in an intervention and what is not²⁰.

The COM-B model is a framework for understanding behaviour and how to change behaviour²¹. This model was generated to develop a behaviour change design methodology informed by behaviour theory. The authors identified three main factors that are considered sufficient and necessary for behaviour change: the necessary skills, a strong intention to perform the behaviour, and no environmental constraints to make the behaviour possible¹⁸. These are operationalised as Capability, Motivation, and Opportunity respectively. In the COM-B model, the three components interact and influence each other, hence, altering one has the potential to alter the others. In the COM-B model, Capability is defined as “the individual’s psychological and physical capacity to engage in the behaviour”¹⁸ through, for example, knowledge or skills; and it is divided into Physical Capability and Psychological Capability. Opportunity is defined as “all the factors that lie outside the individual that make the behaviour possible or prompt it”¹⁸; and it is subdivided into social opportunity and physical opportunity. Finally, Motivation is defined as “all those brain processes that energise and direct behaviour”¹⁸ such as habitual processes, emotional responses, and analytical decision-making; and it is subdivided into reflexive motivation and automatic motivation.

The Theoretical Domains Framework (TDF) and the COM-B model represent potentially useful theories of behaviour that can be used in the context of stillbirth prevention because they incorporate internal factors, such as attitudes, co-occurring behaviours and co-founding factors²². The importance of the social context has been described in the literature in relation to behaviour change during pregnancy²³. Moreover, it is also well established that the behaviours that have been associated with an increased risk of stillbirth often can co-occur (e.g., smoking and alcohol consumption, smoking and illicit drug use, illicit drug use and lack of attendance at antenatal care, substance use and physical inactivity)^6,24,25. Therefore, utilising a theory that takes into account factors that influence behaviour such as the physical and social environment is important to understand behaviour change during pregnancy²⁶. The COM-B model has not been widely tested in the context of stillbirth prevention. However, previous research mapping factors influencing dietary behaviour, physical activity, smoking, and alcohol use²³ during pregnancy to the elements of the COM-B has concluded that all its factors (capability, opportunity and motivation) have a role in directing behaviour²⁶.

The Behaviour Change Wheel (BCW) is a systematic framework providing a methodology for designing behaviour change interventions. This methodology proposes the elements of the COM-B model as mechanisms of action. The BCW provides intervention designers with a systematic process for intervention design composed of three main stages and eight steps exposed in Table 1.

The BCW framework has been used for behaviour change intervention design in the context of pregnancy. For example, Gould et al. (2017) successfully used the BCW to design an intervention to target smoking amongst Australian indigenous pregnant women²⁷. Another example of an intervention designed using the BCT is the “stay-active” smartphone app developed by Smith et al. (2022) to increase physical activity in pregnant women²⁸. The authors of both interventions report that utilising the BCW provided them with a systematic approach that facilitated the process. The process described in the studies published by both authors outlining their use of the BCW to inform the development of their interventions led to the design of two different interventions that are now being tested through feasibility studies^29,30. Hence, there is evidence in the literature that the BCW is a methodology suitable for intervention design applicable to pregnancy.

While the BCW provides a promising approach to informing design of behaviour change interventions that target behaviours associated with increased risk of stillbirth, to date, no intervention has been designed using the BCW and adopting a multi-target approach that might incorporate all of the relevant behaviours. Evidence from public health initiatives implemented in high-income countries provide evidence that further reduction in stillbirth rates is possible in Ireland^31,32. Hence, the main objective of this project is to utilise all of the evidence gathered in earlier stages of its development^33–39 to inform the design of a behaviour change intervention tackling the modifiable risk factors for stillbirth.

Methods

Using all of the evidence generated from the studies composing this thesis, we will follow the process proposed by the BCW for intervention design.

Study status

At the moment, the research team is completing stage 1 of this study and coding the data into the COM-B model as described in the stage one of the “Applying the Behaviour Change Wheel” section.

Conclusion

In summary, following this process will hopefully allow us to define the behaviours that need to be addressed, identify intervention functions, and identify BCTs. This process also will allow us to identify options to translate such BCTs into actual intervention content. Involving PPIs and stakeholders and utilising the APEASE criteria throughout the whole process will enhance the chances of the intervention to be acceptable and effective for its purpose. The following steps will then involve developing an implementation strategy for the designed intervention.