Using the U.S. and U.K. Censuses for Comparative Research

Executive Summary

Researchers, policymakers, and practitioners are constantly interested in international comparisons as a means to generate and test hypotheses and new ideas. Likewise, they have for centuries relied on census data as a key source of information about the nature and dynamics of nations.

This discussion paper, accordingly, reviews key features of the U.S. and U.K. censuses of population, and considers how the two canvasses can be used for comparative research on population, housing, and other key issues. To that end, it offers a guide to the surveys’ respective approaches and definitions, and their similarities and differences—all with an eye to helping researchers assess their utility for bilateral comparisons.

On balance, the paper concludes that the two nations’ censuses—despite their variations of method, terminology, and reporting—hold out exciting potential for comparative analysis.

More specifically, the review finds that:

  • In broad terms, the U.S. and U.K. censuses resemble each other. Despite betraying traces of their divergent original rationales and users, both of these long-running canvasses have over time substantially converged. In recent decades, the two censuses have been carried out similarly. What they ask, the response rates, forms of analysis, and the way data are presented are generally comparable now.

  • At the same time, a number of differences between the censuses create pitfalls for comparative researchers. These differences—while not insuperable barriers to comparative analysis—involve such important issues as the topics covered and questions asked, the categories employed, changes in methodology over time, differences in processing techniques, and differences in the spatial units employed to report results.

  • Yet even so, for all of those differences the two censuses are similar enough to support significant comparison of the U.S. and the U.K. on a wide range of topics. Comparative research can also be carried out for a wide range of spatial units from nations to neighborhoods. And it can produce both comparative snapshots and trends comparisons over time.

In sum, the U.S. and U.K. censuses—despite their idiosyncracies—are more similar than different and furnish valuable information for comparative research. By employing a little ingenuity, researchers, policymakers, and practitioners will find in the two censuses a rich resource for future inquiry into the similarities and differences of the two countries.