Systematically identified evidence concerning modifiable and contextual barriers and enablers can guide the choice of theory and inform behaviour change intervention design. The Bayesian approach can enable the comparison of the extent to which a barrier or enabler influences behaviour and helps in concluding on the uncertainty in the evidence. It can be used to inform intervention development with stakeholders' accounts using qualitative research. The Bayesian approach facilitates the synthesis of qualitative and quantitative evidence. This review evaluates the evidence on the determinants of physical activity among individuals living with heart failure (HF). In HF, physical activity is associated with improved quality of life, reduced hospitalisation, and increased longevity and is a key component of treatment.
Embracing the Bayesian approach in health psychology research, we aimed to synthesise evidence regarding barriers and enablers to physical activity in HF in a way that can inform behaviour change intervention development. Qualitative and observational studies investigating any barriers and enablers to physical activity in adults diagnosed with HF were included in a systemic review with Bayesian meta-analysis following the methodology of Dixon-Woods et al. (2002). Evidence from 19 studies (three qualitative; 16 quantitative studies) was synthesised. Qualitative evidence was annotated using the Theoretical Domains Framework to identify determinants of physical activity participation and represented as a prior distribution using an expert elicitation task. The maximum a posteriori probability (MAP) was calculated as a summary statistic for the probability distribution of physical activity conditioned on each determinant, according to qualitative evidence alone (i.e., prior) and qualitative and quantitative evidence combined (i.e., posterior). The uncertainty in the evidence was expressed using Credible Intervals (CrI). Evidence concerning the modifiable barriers and enablers is highly uncertain: social support(MAP=0.11,CrI:[0.08;0.13]),negative attitude(MAP=0.22,CrI:[0.17;0.27]),positive attitude(MAP=0.27,CrI:[0.23;0.31]),self-efficacy(MAP=0.31,CrI:[0.29;0.33]),symptom distress(MAP=021,CrI:[0.18;0.24]). The contextual barriers are age(MAP=0.22,CrI:[0.22;0.23]), low Left Ventricular Ejection Fraction(MAP=0.20,CrI:[0.19;0.22]), and depression(MAP=0.14,CrI:[0.12;0.16]), low, moderate, and high uncertainty in the evidence, respectively. This work extends the limited research on the modifiable barriers and enablers for physical activity participation by individuals living with HF. The review supports the usefulness of the Bayesian approach in informing intervention development and identifies determinants to physical activity that warrant consideration when designing interventions.