title: Optimising digital cardiac rehabilitation using the multiphase optimization strategy
Creators: name: Kenny, Eanna
Publisher: name: University of Galway
Year: 2025
Subjects: subject: cardiac rehabilitation
subject: Cardiovascular disease (CVD)
subject: digital cardiac rehabilitation
subject: Arts, Social Sciences &amp; Celtic Studies
subject: Psychology
subject: FOS: Psychology
subject: Health psychology

description: Background. Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Cardiac rehabilitation (CR) is a complex intervention that seeks to improve the functional capacity, wellbeing, and health-related quality of life of patients with CVD. Despite strong evidence supporting the clinical and cost-effectiveness of CR, its utilisation remains low due to various patient-, clinician-, and service-level barriers. Digital CR offers a promising solution to some of these challenges, yet its components and mechanisms of change are not well-defined. The Multiphase Optimization Strategy (MOST) provides a framework that allows the effects of individual components of complex interventions to be studied. Aims. This research aimed to (1) determine the effectiveness of digital CR and identify the active ingredients in these interventions, (2) qualitatively explore patient experiences of participating in digital CR, (3) develop a conceptual model of digital CR, and (4) explore the feasibility and acceptability of conducting an optimisation randomised controlled trial of a digital CR intervention. Methods. Four studies were conducted to achieve the aims of this thesis. Study 1 involved a systematic review and meta-analysis to synthesise the evidence for digital CR interventions and identify the behaviour change techniques (BCTs) associated with effective interventions. In Study 2, thematic analysis was used to explore patient experiences of participating in digital CR programmes. Study 3 aimed to develop a conceptual model of digital CR using used tools and frameworks from behavioural science, including the Behaviour Change Wheel, the Capability Opportunity Motivation Behaviour (COM-B) model, and Theoretical Domains Framework to synthesise the findings from the systematic review, qualitative research, and a review of international guidelines for CR. Study 4 is a protocol for a mixed methods study that will explore the feasibility and acceptability of conducting an optimisation randomised controlled trial of a digital CR intervention. Key stakeholders, including a Patient and Public Involvement panel, were engaged with throughout the programme of research. Findings. Study 1 found that digital CR was associated with significant improvements in daily steps, light physical activity, medication adherence, functional capacity, and low- density lipoprotein-cholesterol when compared to usual care, and was comparable to centre- based CR on all outcomes. More effective interventions included BCTs belonging to the following BCT domains: feedback and monitoring, goals and planning, natural consequences, and social support. Study 2 found that digital CR helped to empower and support participants by providing them with the tools to modify their lifestyle and manage their recovery. However, participants reported challenges when communicating online and expressed a desire for more social interaction with peers. The conceptual model developed in Study 3 outlines the causal process through which digital CR can enhance patient outcomes. It specifies intervention components (e.g., education), targeted outcomes (e.g., physical activity), and theorised mediating variables (e.g., knowledge). Study 4 encountered significant delays due to data protection and intellectual property concerns, highlighting the challenges of conducting research with digital health technology. The findings from this study will provide insights into the feasibility and acceptability of conducting a fully powered optimisation randomised controlled trial of a digital CR intervention. Conclusions. This thesis applies multiple methods to develop the evidence base for the optimisation of digital CR. It presents evidence supporting the effectiveness of digital CR and offers insights into the design and structure of these interventions that contribute to their success. Additionally, it explores the patient experience of participating in digital CR programmes and identifies the key factors that shaped these experiences. The conceptual model, developed through a synthesis of quantitative and qualitative evidence using behavioural science frameworks, provides a strong foundation for evaluating a digital CR intervention in an optimisation randomised controlled trial. The description of the conceptual model development process serves as an example of the preparatory work that can be conducted within MOST, and demonstrates how behavioural science can enhance this phase. The research makes a significant contribution to the literature on digital CR, the preparation phase of MOST, and the application of tools and frameworks that can support this work. The findings offer important implications for the development and optimisation of effective digital CR programmes.