Social prescribing for people in vulnerable situations in Europe: Protocol for a process evaluation of an RCT in eight countries

This article presents the protocol for a process evaluation accompanying the Social Prescribing Europe (SP-EU) randomized controlled trial. Social prescribing connects people with non-clinical community resources—such as physical activity, gardening, cultural programs, social groups, or financial and housing support—to address social needs that influence physical and mental health.

The SP-EU project focuses on three populations that may experience heightened health risks and barriers to accessing services:

* LGBTIQ+ people
* Refugees and first-generation immigrants
* Adults aged 65 and older who live alone

The adapted social-prescribing pathway will be tested at ten hubs across Belgium, Croatia, Denmark, Germany, Poland, Portugal, Spain, and Switzerland. Participants assigned to the intervention will work with trained link workers who help identify their needs and connect them with appropriate community activities. The comparison group will receive usual care, consisting of written information about available community services. The trial’s primary outcome is whether participants attend at least one non-medical community service within six months.

The process evaluation is designed to explain not only whether the intervention works, but also how, why, for whom, and under what conditions it works. Researchers will assess the program’s reach, fidelity, participant engagement, acceptability, cultural and organizational context, unintended consequences, and differences in implementation across countries. They will also examine how the usual-care pathway operates and what participants find helpful or insufficient about it.

The study uses a convergent mixed-methods design. Quantitative information will be gathered from link-worker records, electronic case-report forms, hub-level recruitment and retention data, and a digital tool that identifies local community activities. Qualitative data will come from interviews and focus groups with approximately 50 participants, including patients, general practitioners, link workers, study nurses, and research coordinators. Community workers may also be interviewed about the accessibility and quality of local services.

Quantitative findings will be analyzed descriptively, while interview data will undergo framework analysis. Researchers will then integrate both forms of evidence using the social-prescribing pathway—individual, referrer, link worker, and community activity—and the Context and Capabilities for Integrating Care framework. This approach will help identify where implementation succeeded, departed from the intended model, or produced unexpected outcomes.

People with lived experience helped co-create the intervention and trial procedures, and local advisory boards will continue contributing throughout implementation and interpretation. Ultimately, the evaluation will provide important context for understanding the trial’s outcomes and inform European policies on using social prescribing to reduce health inequities and improve the well-being of people in vulnerable situations.