Table 2.

TABS scheme for qualitative assessment of annotation accuracy.

Category	Description	Comment
0	Total agreement	Original annotation is correct, but annotations may be only semantically (but not computationally) identical
1	Typographical error	Original annotation contains typographical errors that may be propagated in the database
2	Undefined source	Original annotation contains undefined terms, non-homology based predictions, and so on
3	Under-prediction	Original annotation predicts a nonspecific biochemical function although a more detailed prediction could have been made
4	False negative	Original annotation does not provide predicted function although there is sufficient evidence to characterize the query protein
5	Domain error	Original annotation overlooks different domain structure of query and reference proteins
6	Over-prediction	Original annotation predicts a specific biochemical function without sufficient supporting evidence
7	False positive	Original annotation predicts function without any supporting evidence

(from Ouzounis and Karp, Genome Biol. 2002;3(2):COMMENT2001)