• Our ‘global health metadata catalogue’ (GHMC) is being developed collaboratively under the auspices of the International Methodology Consortium for Coded Health Information (IMECCHI – see http://www.imecchi.org).
• Data of interest includes: administrative accounts of codified individual level health care encounters.
• Data are being collected from a diverse combination of sources including: health insurance registries, inpatient care, day surgery, physician services, homecare, vital statistics and others.
• The databases of interest are national-level databases describing individual care encounters and/or health episodes recorded using any of a number of coding systems (i.e. ICD 9-CM, ICD 10, SNOMED).
• Using a combination of the Internet, telephone interviews, e-mail, written correspondence, and document analysis, we have gathered ‘metadata’ in three distinct layers in a relational database that is viewable by users on the Internet (www.imecchi.org).
• The database is relational such that information in deeper layers collapses upward to higher layers, sometimes with multiple items in the deeper layers.
• Layer 1 of the database consists of simple contact information on national-level agencies or individuals who hold coded health data.
• Layer 2 provides a nominal description for each individual dataset held by any given agency.
• Layer 3 consists of any supporting documents or validity elements that further describe the databases identified.
• For information-rich countries we have observed that it is possible to populate all 3 layers of the metadata-database. In contrast, for many developing countries, only information is available for layer 1.