# RECONCEPTUALIZING REHABILITATION RESEARCH VIA AN ENACTIVE FRAMEWORK AND A RADICALLY INTERDISCIPLINARY CROSS-ANALYSIS: A STUDY PROTOCOL ON FATIGUE IN POST COVID-19 CONDITION (PCC)

## TL;DR

This study introduces a new interdisciplinary approach to understanding fatigue in post-COVID-19 condition by combining multiple research methods and perspectives.

## Contribution

The paper proposes a radically interdisciplinary cross-analysis methodology grounded in an enactive framework to study complex symptoms like fatigue.

## Key findings

- A mixed-methods protocol is outlined for studying post-COVID fatigue using diverse assessments and interdisciplinary analysis.
- The enactive framework is suggested as a way to integrate biological, psychological, and sociocultural aspects of health.
- The approach aims to provide a more holistic understanding of complex symptoms through cross-disciplinary collaboration.

## Abstract

To present a radically interdisciplinary research approach to ill-defined symptoms, with a focus on fatigue as a major symptom of post COVID-19 condition, where multiple and, to date, rarely combined approaches may yield a fuller understanding of these symptoms.

Protocol for a mixed-methods study comprising an interdisciplinary cross-analysis.

35 persons with post COVID-19 condition and severe fatigue were included, and 35 age-, sex-, and educationally matched controls who recovered from COVID-19 without post COVID-19 condition.

Participants were assessed by a multidisciplinary research team as follows: physician assessment; blood and urinalysis; spirometry and physical performance tests; neuropsychological tests; structural and functional magnetic resonance imaging; extended immunological tests (cytokines); and qualitative phenomenological analysis of interviews. Data will be analysed in accordance with established methods in each of these research fields and by a cross-analysis methodology developed from within an enactive framework. This framework encompasses a focus on neuroscientific, physiological, and experiential aspects of the person as a living being in their sociocultural world.

The biopsychosocial model needs to be implemented in research according to methods that allow radically different research paradigms, typically seen as incommensurable, to inform each other in a non-reductionist manner. One application of such an approach is therefore described.

Several of the most debilitating symptoms in medicine, such as fatigue and pain, are highly non-specific and both difficult for the patient to describe and for the caregiver to interpret. The underlying factors contributing to such symptoms are often complex and multiple. Our purpose is to develop a cross-analysis methodology, developed from within an enactive interpretation of the biopsychosocial model that allows for a focus on neuroscientific, physiological, and experiential aspects of the person as a living being in their sociocultural world, and to do so in order to achieve a more holistic and clinically clarifying way of understanding complex conditions, such as post-COVID fatigue. Traditionally conceived, the biopsychosocial model of disease acknowledges this complexity, but does not as such suggest how to capture it for clinical or research purposes. In this paper, we propose a radically interdisciplinary approach, where experts from basic medical science, clinical medicine, psychology, phenomenology, and ethics collaborate, each with their specific perspectives and methods. We then combine and enrich the obtained results through a cross-analysis. We suggest that an enactively modernized biopsychosocial framework is especially suitable for this collaboration, as it acknowledges the close interrelation between mind, body, and environment, and can facilitate cross-analyses of data in this project.