The project of the Belgian Ageing Studies uses a participatory methodology, namely peer research. Older adults were involved in the study, not only as the research target group, but also as experts and actors by playing a role as volunteers in the research process. They play a crucial role in the planning, the design, and the realisation of the research project, as well as in the development of local policy plans on the basis of the findings of the research.

In every municipality, an older volunteer is responsible for guiding, monitoring and supervising the research process. Such a supervisor brings together representatives from local policy makers, older volunteers, local senior advisory boards and stakeholders in a steering committee of four or five participants. He or she also provides training to the older, voluntary interviewers. Every supervisor is trained and supported by the Belgian Ageing Studies-research team.

In each municipality, on average between 30 and 50 volunteers participate in the project. In order to find these volunteers, an intensive recruitment campaign is set up, which is identical in every municipality. Essentially, older volunteers adopt the role of expert researchers. They invite respondents to participate in the research project by sending them a letter and subsequently contacting them face to face a few days later. The questionnaire is meant to be self-administered, but volunteers are allowed to clarify the meaning of questions, when this is requested. This system has the advantages of face-to-face research (which has a higher response rate), while minimising the social desirability. All volunteers are trained and followed by the local supervisor and a municipal professional.

This system of peer-research enriches the research-design and results in more complete questionnaires and a high response rate. Depending on the municipality, between 65% and 85% of the older people contacted filled in the questionnaire.