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2020 MEDLINE/PubMed Baseline: 30,420,660 Citations Found

Element NameCitationsOccurrencesMin OccursAvg OccursMax OccursMin LenAvg LenMax Len
PMID30,420,66030,420,66011117.648
DateCompleted28,386,73728,386,737111888
DateRevised30,420,66030,420,660111888
ISSN30,034,98130,034,981111999
IssnType=Electronic9,953,9979,953,997111999
IssnType=Print20,080,98420,080,984111999
IssnTypeCHECK030,034,981000000
Volume29,791,31529,791,31511112.21207
Issue26,862,69126,862,69111111.44132
PubDate30,420,66030,420,660111811.4642
Title30,420,66030,420,660111236.41239
ISOAbbreviation30,416,70330,416,703111116.51108
ArticleTitle30,420,66030,420,660111089.561,999
MedlinePgn29,989,76629,989,76611115.83173
ELocationID10,619,86812,569,41411.182123.49246
Valid=Y10,619,73712,569,25411.182123.49246
Valid=N14216011.132221.7933
ValidCHECK012,569,414000000
EIdType=doi10,550,75110,550,753112124.2977
EIdType=pii2,018,6612,018,661111119.3246
EIdTypeCHECK012,569,414000000
Abstract19,936,67519,936,67511101281.7824,244
AbstractText19,936,67534,273,90711.72250745.1824,244
CopyrightInformation3,486,7813,486,781111160.321,245
Structured4,445,7424,445,742111141691.7214,389
AbstractText4,445,74218,782,97414.22250399.6514,389
NlmCategory:BACKGROUND1,821,3541,870,60811.03510360.9610,479
NlmCategory:OBJECTIVE2,498,1152,507,1891185259.658,609
NlmCategory:METHODS3,557,0394,367,24611.23208381.248,466
NlmCategory:RESULTS3,665,6763,673,6711169621.949,152
NlmCategory:CONCLUSIONS3,825,8293,949,40111.0389298.368,247
NlmCategory:UNASSIGNED170,228581,52913.42169413.6214,389
NlmCategory:UNLABELLED00000000
Author29,777,582122,111,02114.15,425112.861,560
Valid=Y29,777,572122,090,72714.15,425112.861,560
Valid=N14,37120,29411.4144314.6996
ValidCHECK0122,111,021000000
LastName29,740,398121,879,56414.15,39916.62176
ForeName29,544,422121,198,81214.15,39914.81162
Initials29,705,517121,753,50814.15,39911.418
Suffix490,192578,55911.185012.45211
CollectiveName212,645231,45611.09163141.391,560
Identifier1,048,8601,884,48011.8396127.8573
Affiliation19,499,90151,513,97012.646,9221119.1116,988
AffiliationIdentifier31,560859,215127.225,8382937.3459
Language30,420,66030,508,711116333
Grant3,211,0528,831,13312.75358240.471,279
GrantID3,072,8298,545,74012.78358111.151,251
Acronym2,579,9987,415,18412.8735822.0231
Agency3,211,0278,831,05112.75358115.51933
Country3,029,8988,337,77812.75358212.9752
PublicationType30,420,55052,696,46611.7310418.0656
DataBank359,703367,95811.0224099.92120,007
DataBankName359,703367,95811.022408.7818
AccessionNumber359,7034,170,105111.5910,00008.0462
ArticleDate8,560,0708,560,070111888
VernacularTitle3,650,6863,650,686111178.091,159
Country30,420,65430,420,65411149.9935
MedlineTA30,420,65030,420,650111115.51108
NlmUniqueID30,420,66030,420,66011177.429
ISSNLinking29,830,67429,830,674111999
Chemical14,182,99554,288,28613.8353421.21246
RegistryNumber14,182,99554,288,28613.835314.6415
NameOfSubstance14,182,99554,288,28613.8353216.57245
SupplMeshName106,301114,73311.0810524.86177
Type=Disease84,55988,09111.049528.14177
Type=Protocol20,48825,22111.2310513.4843
Type=Organism1,3341,42111.0741023.7558
TypeCHECK0114,733000000
CitationSubset27,078,07930,526,47111.13611.993
GeneSymbol59,507126,19312.122514.5141
CommentsCorrections1,738,4372,187,32211.26108039.27365
RefType=AssociatedDataset677011.0432237.2765
RefType=AssociatedPublication667011.0632239.89111
RefType=Cites00000000
RefType=CommentIn726,412936,07211.2958039.37150
RefType=CommentOn817,100934,13511.1473038.16227
RefType=CorrectedandRepublishedFrom00000000
RefType=CorrectedandRepublishedIn00000000
RefType=ErratumFor65,50966,93211.02961640.21308
RefType=ErratumIn204,046208,55511.0210041.84334
RefType=ExpressionOfConcernFor39652911.34411838.1167
RefType=ExpressionOfConcernIn49452711.0732135.7162
RefType=OriginalReportIn1,2621,31111.0432439.8660
RefType=PartialRetractionIn00000000
RefType=PartialRetractionOf00000000
RefType=ReprintIn2,9282,97111.0141941.81103
RefType=ReprintOf2,9542,9661141840.93195
RefType=RepublishedFrom1,5511,5571121939.4293
RefType=RepublishedIn1,3511,3571122139.42112
RefType=RetractedandRepublishedFrom881113137.2545
RefType=RetractedandRepublishedIn881112834.7540
RefType=RetractionIn7,1797,28511.0171644.64365
RefType=RetractionOf7,1347,66511.071071670.66307
RefType=SummaryForPatientsIn1,2951,31111.0132137.6564
RefType=UpdateIn6,9606,99811.0122443.3753
RefType=UpdateOf6,9946,9951122343.92100
RefTypeCHECK02,187,322000000
MeshHeading26,365,140279,331,447110.5968214.12104
DescriptorName26,365,140279,331,447110.5968214.12104
Descriptor=Major14,334,69128,759,44612.0144216.53104
Descriptor=Not Major26,088,646250,572,00119.660213.84104
DescriptorCHECK0279,331,447000000
QualifierName23,558,282151,163,36116.4272511.2929
Qualifier=Major22,622,01766,703,97312.9535511.329
Qualifier=Not Major18,419,98984,459,38814.5972511.2829
QualifierCHECK0151,163,361000000
PersonalNameSubject181,400205,86711.1328212.9775
LastName181,400205,86711.132817.3469
ForeName175,878198,80511.132814.3448
Initials175,878198,80511.132811.429
Suffix1,3321,37311.03429.8826
NumberOfReferences1,546,2391,546,23911112.18
OtherID1,484,4421,577,29111.066112.48391
NLM Source21,17821,178111510.0136
OtherAbstract131,793140,05111.06601226.623,720
AbstractText131,793140,05111.06601226.623,720
CopyrightInformation00000000
Keyword6,254,12227,990,84514.48245016.051,727
Keyword=Major2,937,60810,085,32213.43125016.291,727
Keyword=Not Major3,396,06617,905,52315.27245015.92999
KeywordCHECK027,990,845000000
GeneralNote155,634289,27811.8632234.211,226
SpaceFlightMission4,22119,54624.6312613.8728
Investigator55,3573,074,791155.543,741114.12715
Pre2008Investigator8,92410,27511.156731.0596
LastName8,92410,27511.15626.6916
ForeName8,91610,26411.15612.79
Initials8,91610,26411.15611.852
Suffix161611122.193
Identifier00000000
Affiliation8,92310,27411.156319.8183
AffiliationIdentifier00000000
Post2008Investigator46,4333,064,5161663,74110715
LastName46,4333,064,5161663,74117.01158
ForeName46,3353,046,583165.753,74014.75190
Initials46,3343,045,811165.743,74011.28
Suffix3,0745,56011.813812.3425
Identifier2211119123.519
Affiliation1,48055,529137.521,142363.06701
AffiliationIdentifier00000000
Reference5,513,244173,572,772131.484,9251338.24190

ElementCount
Average Record Size2,150

ElementAverageMax
Words in Title12.317341
Words in Abstract193.493,576

Abstract SizeCount
AB Size Zero10,495,995
AB Size 1 - 9996,177,406
AB Size 1,000 - 1,99912,247,939
AB Size 2,000 - 2,9991,413,964
AB Size 3,000 - 3,99971,308
AB Size 4,000 - 4,9999,049
AB Size > 5,0004,999

IndexingMethodCounts
Automated2,352,782
NONE27,378,019
Curated689,859

MeSH HeadingCounts
Number of MH Occurrences with NO SHs171,443,048
Number of MH Occurrences with ONE SH74,817,827
Number of MH Occurrences with >= 1 SH12,247,939
Number of MH Occurrences with Type=Geographic3,479,408

CollectiveName Author, and Investigator Related Counts:Count
Citations containing ONLY CollectiveName37,184
Citations containing BOTH CollectiveName AND Author175,461
Citations containing BOTH CollectiveName AND Investigator46,405
Citations containing BOTH Author AND Investigator52,300
Citations containing BOTH Investigator AND Owned by NASA3,903
Citations containing Investigator without Collective8,952

Citation StatusCount
In-Data-Review322,961
In-Process276,945
MEDLINE26,365,156
PubMed-not-MEDLINE3,096,103
Publisher359,495

Article PubModelCount
Electronic956,008
Electronic-Print53,014
Electronic-eCollection674,815
Print21,860,590
Print-Electronic6,876,233

Article JournalIssue CitedMediumCount
Internet10,150,518
Print20,270,142

Owner CountsMedlineCitationGeneralNoteKeyWordOtherAbstract
NLM30,284,44111,0161,992,3890
NASA10,9414,61612,957409
PIP39,73863,79468,86753,162
KIE32,015209,60873,8153,032
HSR9,79224400
HMD43,733000
NOTNLM004,106,5420
NLM-AUTO0000
HHS0000
AAMC0000
AIDS0005,342
Publisher00077,880
plain-language-summary000226

Grant CountryOccurrences
63 distinct values in 2020 (12 in 2019) 
Country coded as <Country/>493,355
Argentina26
Australia12
Austria8,714
Belgium1
Brasil2
Brazil26
Canada80,695
Canonsburg, Pennsylvania1
Chile2
China249
Colombia4
Czech Republic4
Denmark3
Dublin, Ireland1
EU1
Egypt2
España1
European Union1
France12
Germany60
Hong Kong1
India531
Indonesia3
International99,817
Ireland498
Israel4
Italy12,617
Japan10
Korea692
Kuwait3
Lebanon3
México1
Mexico4
Netherlands10
None65
Norway1
Oman1
Place3
Poland8
Portugal6
Republic of Korea458
Russia1
Russian Federation1
Russian Forderation1
Saudi Arabia1
Serbia1
Singapore5
South Korea6
South San Francisco, California1
Spain16
Sweden3
Switzerland997
Taiwan27
Thailand6
The Netherlands1
Turkey1
U.S.A.1
UK3
USA2
United Arab Emirates3
United Kingdom517,711
United Kingdom of Great Britain and Northern Ireland1
United States7,614,392
United States of America44

CitationSubsetCounts
AIM2,291,783
B10,444
C7,570
D625,910
E100,550
F8,015
H287,047
IM23,627,800
J68,947
K25,637
N743,640
OM2,010,888
Q201,892
QIS13,539
QO24,427
R3,605
S194,912
T77,304
X202,561

PublicationTypeCount
Adaptive Clinical Trial16
Address5,118
Autobiography3,671
Bibliography15,952
Biography178,435
Case Reports2,060,592
Classical Article6,487
Clinical Conference7,283
Clinical Study3,394
Clinical Trial519,552
Clinical Trial Protocol1,504
Clinical Trial, Phase I19,672
Clinical Trial, Phase II31,644
Clinical Trial, Phase III15,930
Clinical Trial, Phase IV1,798
Clinical Trial, Veterinary1,132
Collected Works2
Comment817,154
Comparative Study1,847,038
Congress65,844
Consensus Development Conference11,403
Consensus Development Conference, NIH776
Controlled Clinical Trial93,390
Corrected and Republished Article1,564
Dataset735
Dictionary542
Directory6,641
Duplicate Publication892
Editorial510,684
English Abstract1,515,697
Equivalence Trial431
Evaluation Studies26
Evaluation Study247,665
Expression of Concern397
Festschrift1,655
Government Publication175
Guideline16,189
Historical Article355,366
Interactive Tutorial267
Interview28,819
Introductory Journal Article50,308
Journal Article28,350,724
Lecture6,740
Legal Case10,990
Legislation1,670
Letter1,053,680
Meta-Analysis107,826
Multicenter Study261,866
News197,429
Newspaper Article18,293
Observational Study70,845
Observational Study, Veterinary69
Overall27,764
Patient Education Handout5,045
Periodical Index321
Personal Narrative4,351
Portrait47,543
Practice Guideline25,615
Pragmatic Clinical Trial1,235
Published Erratum67,611
Randomized Controlled Trial495,344
Research Support, American Recovery and Reinvestment Act2,023
Research Support, N.I.H., Extramural1,107,581
Research Support, N.I.H., Intramural52,918
Research Support, Non-U.S. Gov't7,216,461
Research Support, U.S. Gov't, Non-P.H.S.819,831
Research Support, U.S. Gov't, P.H.S.1,465,952
Retracted Publication7,181
Retraction of Publication7,482
Review2,565,505
Scientific Integrity Review255
Systematic Review117,494
Technical Report2,878
Twin Study8,346
Validation Study97,798
Video-Audio Media23,157
Webcast802
Webcasts1

ELocationID EIdTypeCount
DOI or PII, MedlinePgn Not Found161,768
DOI or PII, MedlinePgn Found8,508,556
DOI and PII, MedlinePgn Not Found265,014
DOI and PII, MedlinePgn Found1,684,530

PMID VersionCount
130,419,054
21,358
3205
425
59
63
72
82
91
101

Last Reviewed: July 27, 2020