What is it about?

Hard-to-reach is an expression largely used to describe those sections of the community difficult to involve in public participation or to reach by services of which they are the intended beneficiaries. This paper discusses the meaning of hard-to-reach in the context of administrative sources and in relation to the traditional hard-to-count groups in censuses and surveys. At first glance, administrative data might offer the potential to improve frame coverage for some target populations, but may also lead to other hard-to-reach or “hidden” populations for different population groups.

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Why is it important?

The answer to the rather ambitious question: ‘Is it possible to replace field collection with administrative sources by at the same time ensuring the inclusion and representation of HTR groups?’, is that the understanding of hard-to-reach populations varies from country to country, and that there are many ongoing initiatives in individual countries aiming at capturing and improving the access to hard-to-reach populations. The diverging understanding of hard-to-reach populations in administrative sources could point to the need of a common framework of concepts and some general guidelines in the field, starting from the identification of cross-cutting issues faced by countries.


We hope the article provides a useful basis for further possible work to improve access to hard-to-reach groups using administrative data, at a time when an increasing number of countries rely on register-based statistics, and when the call to 'leave no-one behind' enshrined in the 2030 Agenda for Sustainable Development provides the backdrop for improving the quality and coverage of statistics.

Donatella Zindato
Istat (Italian National Institute of Statistics)

Read the Original

This page is a summary of: Hard-to-reach population groups in administrative sources: main challenges and future work, Statistical Journal of the IAOS, December 2023, IOS Press,
DOI: 10.3233/sji-230074.
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