  The use of registers has been increasingly popular in the field of population
census because of its advantages over the traditional census. While the
traditional census requires a large amount of fieldwork and data collection,
the registered-based census can rely on pre-existing administrative data. As a
result, the register-based census can save both time and budget. Thailand
explored a use of the register-based census in 2020. In this paper, the authors
layout the methodology in an aspect of data preparation and integration as well
as analyze data quality of the register-based census compared with the
traditional census in Chachoengsao province, Thailand. In addition, we compared
conceptual frameworks that are commonly used for a register-based census in
several countries and the number of databases (a recent single database VS
multiple databases) used to construct the register-based census. We found that
using a conceptual framework that counts the number of populations based on the
main census variables on a single recent database is better than using a
framework that counts population who appears on many registers in term of
overcoverage and data distribution regarding to sex. This provides the evidence
of using one recent and complete database is sufficient for conducting the
register-based census. The authors end up with recommendations for conducing
the register-based census.
