Popularly known as “the data behind the data”, metadata refers to the coverage, temporal reference, distribution and other general characteristics of the corresponding statistical source, as well as to an entire set of technical characteristics regarding the methodology used for their production.

The term is used for the documentation of different issues of the statistical data produced by Central Statistical Offices and other integrants of national General Statistical Systems. Part of them are also disseminated by International Organizations in their general statistical publications.

Metadata are closely related with the fact that credibility is provided by users (either those preparing National Accounts, business associations, academic researchers and consultants, etc). In fact, users are often confronted by some difficulties of interpretation when comparing statistics compiled over time within one agency and by agencies in different countries as well as by different international organizations:

  • conceptual differences arising from the use of different variable definitions, units and classifications;
  • operational differences flowing out of differences in data collection and processing practices by countries, and;
  • different practices in the presentation of data.

UNWTO Tourism Statistics Metadata Project: General Guidelines for documenting tourism statistics is part of an effort by the international community aimed at providing some sort of guidance as to how national statistics-producing bodies may provide users with the information that, though normally left out of the data tables, is important for users to properly analyze the figures. The project shares some components from the Statistical Data and Metadata Exchange (SDMX) ( or and contains the following three phases:

  • inventorying data sources;
  • inventorying available data related to tourism variables;
  • checking the quality of data related to a potential TSA exercise.

It includes the documentation of a different set of statistical inputs –like standards forms for seven types of data sources and a standard check list for identifying available information on key variables-, as well as a comprehensive questionnaire on TSA exercises – both on conceptual issues and main results.

It also includes a multilingual glossary of basic terms in tourism statistics.

Finally, as a complementary initiative, UNWTO periodically requests a sample of questionnaires used by different countries in main tourism statistical surveys