Integrated Taxonomic Information System - Standards
ITIS was founded with a charter to develop, scientifically review, improve, and maintain a taxonomic information system. To help accomplish this goal standards and guidelines have been established.
Data conform with the International Code of Nomenclature for algae, fungi, and plants (ICN), the International Code of Nomenclature of Prokaryotes (ICNP) , and the International Code of Zoological Nomenclature (ICZN).
seven kingdom system has been adopted as a standard. The kingdoms are Bacteria, Protozoa, Plantae, Fungi, Animalia, Chromista and Archaea, each with a defined set of ranks.
Quality indicators are associated with each record. Global Species Completeness and Latest Record Review are found on names at the rank of Genus and above. Global Species Completeness indicates whether all known, named, modern species (extant or recently extinct) for that taxon were incorporated into ITIS at the time of review. Latest Record Review represents the year that the record was last reviewed by ITIS. Both quality indicators can be used in evaluating the timeliness of a group's peer review.
All names have a Record Credibility Rating - the ITIS "level of review" value - associated with them. The highest value, Verified Standards Met, indicates that all elements in the record and the position of the scientific name in the hierarchy are understood to be accurate and supported by one or more credible references. If data in the record have been reviewed but are incomplete or contain accuracy, placement, or nomenclatural issues, or are from a non-peer reviewed source, a rating of Verified Minimum Standards Met is assigned. When the ITIS database was initially populated with NODC records, each name was assigned a rating of Unverified. As efforts to improve the quality of ITIS legacy data continue, more than 58% of the original NODC records have now been rated as Verified.
The ITIS Data Definition has more details about data quality indicators.