Community-Based Participatory Research (CBPR) is often understood primarily as an ethical approach to including vulnerable groups1. This article argues that, beyond this, CBPR represents a central precondition for the methodological quality and epistemic validity of scientific research. Drawing on a detailed analysis of an empirical case from the field of sign language interpreting, we show how missing or inadequate participation can affect various phases of the research process, from the development of the research question and the design of the study to data collection, analysis, and the interpretation of results.

The analysis makes clear that a lack of involvement of the affected communities can lead to fundamental methodological problems, including insufficiently validated survey instruments, undifferentiated samples, and conclusions that are not adequately substantiated. Furthermore, it shows that these deficits not only restrict the explanatory power of scientific findings but can also lastingly damage the trust marginalised groups place in scientific institutions.

Particular attention is given to the development and use of so-called Sign Language Oriented Easy Language Plus (SEL+), which exemplifies how a lack of participatory coordination can lead to methodological, linguistic, and cultural tensions. The article situates this problem in the broader context of structural power relations and epistemic inequalities within the academic system. Finally, with Deaf-Communities Based Participatory Research (D-CBPR), an approach is presented that systematically takes into account the specific linguistic, cultural, and epistemic conditions of Deaf communities. From this, the demand is derived to anchor participation as an independent criterion of scientific quality and to develop appropriate guidelines, for instance within the framework of the German Research Foundation (DFG).

Keywords: Community-Based Participatory Research (CBPR), Deaf Communities, Participatory Research, Methodological Validity, Epistemic Justice, Deaf Studies, Language and Modality, Research Ethics.

Grote, K., Wegner, S., Gerardo B.J.S. & Metzner, A. (2024). The Significance of CBPR for the Quality of Research with Vulnerable Groups [English version].  Deaf Journal, 1 , Article 2-2. Doi: http://dx.doi.org/10.13140/RG.2.2.26209.11366