How a long COVID rehabilitation intervention works: refining its programme theory through a realist-informed...

Although the majority of individuals infected with SARS-CoV-2 recover without treatment, some individuals experience persistent symptoms (long COVID), which may negatively affect their activities and roles of everyday life, leaving them with a profound rehabilitation need. In response to the emergence of long COVID patients, a Danish municipality developed and implemented a structured, out-patient long COVID rehabilitation intervention (The Long COVID Rehabilitation Intervention). To understand how, why and for whom the intervention works, and its functioning, an exploration of the underlying programme theory is required. We thus aimed to explore the interactions between the intervention mechanisms of change, the implementation context and the expected outcomes of The Long COVID Rehabilitation Intervention to confirm or refine the initial programme theory.

We conducted a qualitative study from a realist perspective. Data comprised 12 individual interviews with patients participating in the intervention, a focus group interview with the health professionals delivering the intervention, and an individual interview with the manager of the rehabilitation centre. Transcripts were coded and analysed using a realist analytical approach, enabling for refinement of the initial programme theory expressed with context-mechanism-outcome configurations.

We demonstrated a close interconnectedness among the context-mechanism-outcome configurations, with identity transformation as central to the intervention functioning supported by a person-centred rehabilitation approach, patient education, and peer support. Moreover, we identified acceptance as an overarching mechanism across all context-mechanism-outcome configurations, facilitating a reconceptualisation of beliefs, values, and roles. This empowered the patients to navigate and participate in daily life despite ongoing long COVID symptoms.

Overall, the initial programme theory was confirmed but required refinement to contexts and mechanisms. The theorisation of The Long COVID Intervention clarified how, why, and for whom it worked, informing the development of future long COVID and post-viral rehabilitation interventions.