Table 1:
number of concept changes in SNOMED CT from Release Jan 2002 to July 2009.
| CT | Existing concept made … | N | Error Type |
|---|---|---|---|
| 0 | active: in current use | 2,010 | A-1 |
| 1 | inactive: ‘retired’ without a specified reason | 1,993 | P-1 |
| 2 | inactive: withdrawn because duplication | 9,711 | P-9 |
| 3 | inactive because no longer recognized as a valid clinical concept (outdated) | 1,348 | P-1 |
| 4 | inactive because inherently ambiguous. | 5,829 | P-4 |
| 5 | inactive because found to contain a mistake | 1,204 | P-1 |
| 6 | active with limited clinical value (classification concept or an administrative definition) | 4,461 | A-1 |
| 10 | inactive because moved elsewhere | 14,406 | P-6 |
| 11 | pending move | P-6 | |
| TOTAL | 40,962 |
Legend: CT: concept status as defined in SNOMED CT; N: cumulative number of changes in all versions studied; Error Type: corresponding error in previous version according to the typology described in Table 2