Research in Hard-to-Reach Populations: Challenges and Strategies for Conducting Sexual Violence Studies in Applicants for International Protection Beyond the European General Data Protection Regulation

Document Type : Original Article


1 International Centre for Reproductive Health, Department of Public Health and Primary Care, Ghent University, Ghent, Belgium

2 CARE-ESPRIst, Études et évaluations, University of Liège, Liège, Belgium

3 Institute for International Research on Criminal Policy, Department of Criminology, Criminal Law and Social Law, Ghent University, Ghent, Belgium

4 Research Foundation—Flanders (FWO), Brussels, Belgium


Conducting research in hard-to-reach populations such as applicants for international protection (AIPs) brings along a number of research challenges. This is especially true for sexual violence (SV) research.
We developed a study design with the intent to reach AIPs in a randomized and anonymous manner including potential illiterate respondents as well, while avoiding as much bias as possible. However, this method was developed just before the entry into force of the new European General Data Protection Regulation (GDPR), upon which important new research challenges emerged.

This paper describes the original study design developed to estimate SV prevalence in AIPs in Belgium. We discuss the impact of the GDPR on the recruitment strategy applied to conduct a survey on SV in a randomly selected sample of AIPs, the adapted approach to conduct the study beyond GDPR and lessons learned for future research on sensitive topics in hard-to-reach populations such as AIPs.
To achieve reliable prevalence numbers and provide high-quality data on SV in AIPs while respecting the GDPR regulations, studies will require an approach that has become significantly more time consuming and resourceintensive to implement.


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Volume 11, Issue 9
September 2022
Pages 1934-1941
  • Receive Date: 03 March 2021
  • Revise Date: 13 July 2021
  • Accept Date: 30 August 2021
  • First Publish Date: 31 August 2021