# Taxonomy of chronic illness research recruitment: a restricted scoping review

## TL;DR

This paper creates a taxonomy of factors affecting recruitment in chronic illness research to help researchers design better strategies.

## Contribution

The paper introduces the first comprehensive taxonomy of recruitment factors in chronic illness research.

## Key findings

- Three core components of recruitment were identified: people, place, and project.
- The taxonomy includes factors like researchers' roles, healthcare environments, and research design.
- A practical list of questions was developed to guide recruitment strategy design and reporting.

## Abstract

Chronic illness prevalence is increasing and research recruitment in these populations remains challenging. Individuals with chronic illness often have poorer quality of life, restricted access to hospitals where research occurs, and can be reluctant to participate. Researchers need multiple simultaneous strategies to achieve success. No taxonomy of recruitment factors in chronic illness research could be identified in the literature. This paper aims to describe a comprehensive taxonomy of recruitment for chronic illness research (inclusive of a nursing focus) to inform the design and reporting of recruitment strategies by creating a list of practical questions.

A restricted scoping review was conducted on articles reporting on recruitment factors in chronic illness research. Main search restrictions were the number of years and databases searched with broad eligibility criteria. Included articles were critically assessed and data extracted. A code book was used to examine findings and results sections line by line, both deductively and inductively. The final codebook and the content of the codes informed the taxonomy construction and the practical questions.

Core components of research recruitment were identified as people, place, and project. The component of People included factors of researchers, clinicians, recruiters, and participants roles. The component of Place included factors of national or local research oversight institutions, healthcare environments, and community spaces. Finally, the component of Project included factors of research design, participant research journey, and research promotion. The final taxonomy informed a practical list of questions to aid researchers in the design and reporting of research recruitment strategies.

The chronic illness research recruitment taxonomy describes and characterises factors reported to impact on research recruitment. It provides a framework for designing and reporting on recruitment strategies. While the taxonomy requires further testing, it is the first to offer a broad characterisation of recruitment factors in chronic illness research.

The online version contains supplementary material available at 10.1186/s12913-025-13115-8.