Key MEDLINE® Indicators
| FY2011 | % Change | FY2010 | % Change | FY2009 | % Change | FY2008 | % Change | FY2007 | % Change | |
|---|---|---|---|---|---|---|---|---|---|---|
|
Citations Indexed for MEDLINE
|
724,831 | +4% | 699,420 | -1.9% | 712,675 | +6% | 671,904 | +1% | 670,943 | +8% |
|
MEDLINE/PubMed® Searches7
|
1.8 Billion | +13% | 1.6 Billion | +23% | 1.3 Billion | +65% | 776 Million2 | N.A.2 | 845 Million2 | -6% |
|
879 Million | +9% | 808 Million | +5% | 767 Million | ---- | ---- | ---- | ---- | ---- |
Sub-Total: Scripts/E-Utilities |
956 Million | +24% | 771 Million | +50% | 514 Million | ---- | ---- | ---- | ---- | ---- |
|
Gateway Searches
|
874,000 | -27% | 1.2 Million | -25% | 1.6 Million | +36% | 1.1 Million6 | +51% | 746,0003 | +44% |
|
Journal Titles in MEDLINE
|
5,559 | +1% | 5,484 | +2% | 5,394 | +1% | 5,319 | +2% | 5,1944 | +4% |
|
Journal Titles in
Index Medicus1 |
4,946 | +2% | 4,866 | +2% | 4,759 | +2% | 4,660 | +3% | 4,530 | +3% |
|
Total Citation Data Creation |
845,948 | +10% | 767,470 | +3% | 748,479 | +4% | 720,0976 | +5% | 685,134 | +2% |
|
71,145 | -8% | 77,309 | -12% | 87,970 | -7% | 94,711 | -11% | 105,841 | -13% |
|
774,803 | +12% | 690,161 | +4.5% | 660,509 | +6% | 625,386 | +8% | 579,293 | +6% |
|
Retraction Notices
|
2546 | +15%6 | 221 | +0.5% | 220 | +26% | 174 | +47% | 118 | +22% |
|
Retracted Articles
|
2716 | +12% | 243 | -2% | 249 | +40% | 178 | +44% | 124 | +28% |
|
Partial Retraction Notices5
|
1 | -86% | 7 | +40% | 5 | 0% | 5 | -58% | 12 | ---- |
|
Partially Retracted Articles5
|
1 | -86% | 7 | +40% | 5 | 0% | 5 | -62% | 13 | ---- |
|
Errata
|
7,870 | -7% | 8,433 | +15% | 7,360 | -5% | 7,756 | +10% | 7,035 | -2% |
|
Comments
|
35,049 | -2% | 35,688 | +6.5% | 33,526 | +1% | 33,238 | +4% | 31,956 | +0.9% |
|
Gene Indexing
|
80,297 | +0.3% | 80,042 | -3.5% | 82,932 | +12% | 74,252 | +43% | 51,823 | +11% |
See also additional MEDLINE statistics.
The U.S. Government Fiscal Year (FY) runs from October 1 - September 30.
Note: See Errata Fact Sheet for definitions. NLM began to report retracted articles separately in FY2003. Prior to that the numbers reported were Retraction Notices only.
Note: See Gene Indexing and Entrez Gene. Gene indexing began to be phased in during 4th Quarter FY2001 (Jul-Sep) with several hundred links. In 2005, gene indexing changed from LocusLink, where 10 organisms were in scope, to Entrez Gene, where more than 1,800 organisms are in scope. In 2007, gene indexing was applied to more clinical genetics articles.
1Index Medicus® (ceased in print after December 2004 issue) was a monthly bibliographic listing of current biomedical references derived from MEDLINE. The item remains an online indicator in MEDLINE citations found in PubMed.
2June 2007 implementation of Entrez 2.0 ("portals") resulted in changes to the statistical gathering process. FY2008 represents a new baseline for the data and cannot be compared to FY2007.
3Statistical gathering method was enhanced effective October 2006 to collect previously unreported access.
4Includes about 110 history of medicine journals and 13 bioethics journals.
5NLM began to report partial retractions separately in December 2006.
6Corrected from previously reported numbers:
- FY2008 Gateway Searches previously 998 Million
- FY2008 Total Citation Data Creation previously 726,097
- FY2011 Retraction Notices previously 267 and +21%
- FY2011 Retracted Articles previously 273
7Statistical gathering method refined in FY2009.
