Towards a programme theory for fidelity in the evaluation of complex interventions

Area of Science:

• Rehabilitation science
• Implementation science
• Health services research

Background:

• Stroke survivors in UK care homes face challenges in regaining independence in daily living activities.
• Implementing complex rehabilitation interventions requires careful consideration of fidelity.

Purpose of the Study:

• To investigate fidelity in a complex rehabilitation intervention for stroke patients in UK care homes.
• To construct a programme theory of intervention fidelity for a process evaluation alongside a cluster randomized trial.

Main Methods:

• Programme theory developed using principles of realist evaluation.
• Data collected through semi-structured interviews with occupational therapists (n=17) and critical incident reports (n=20).

Main Results:

• Four mechanisms for investigating fidelity were identified: balancing research/professional requirements, occupational therapists' rapport with staff, re-engineering patient environments, and learning over time.
• Fidelity is characterized by the negotiated nature of implementation within clinical settings, considering individual patient needs.

Conclusions:

• Real-world intervention fidelity is complex and negotiated within clinical settings.
• Existing fidelity frameworks neglect the crucial role of individual and trial-wide learning over time.