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Table representation of search results timeline featuring number of search results per year.
Year
Number of Results
1977
1
1978
4
1979
20
1980
12
1981
20
1982
33
1983
27
1984
33
1985
31
1986
29
1987
37
1988
42
1989
35
1990
31
1991
35
1992
40
1993
50
1994
64
1995
38
1996
40
1997
37
1998
46
1999
47
2000
69
2001
78
2002
72
2003
116
2004
101
2005
136
2006
179
2007
167
2008
174
2009
194
2010
190
2011
220
2012
239
2013
256
2014
288
2015
288
2016
246
2017
281
2018
317
2019
397
2020
464
2021
563
2022
660
2023
542
2024
275
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AMA
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Adaptive Clinical Trial
Address
Autobiography
Bibliography
Biography
Case Reports
Classical Article
Clinical Conference
Clinical Study
Clinical Trial Protocol
Clinical Trial, Phase I
Clinical Trial, Phase II
Clinical Trial, Phase III
Clinical Trial, Phase IV
Clinical Trial, Veterinary
Collected Work
Comment
Comparative Study
Congress
Consensus Development Conference
Consensus Development Conference, NIH
Controlled Clinical Trial
Corrected and Republished Article
Dataset
Dictionary
Directory
Duplicate Publication
Editorial
Electronic Supplementary Materials
English Abstract
Equivalence Trial
Evaluation Study
Expression of Concern
Festschrift
Government Publication
Guideline
Historical Article
Interactive Tutorial
Interview
Introductory Journal Article
Lecture
Legal Case
Legislation
Letter
Multicenter Study
News
Newspaper Article
Observational Study
Observational Study, Veterinary
Overall
Patient Education Handout
Periodical Index
Personal Narrative
Portrait
Practice Guideline
Pragmatic Clinical Trial
Preprint
Published Erratum
Randomized Controlled Trial, Veterinary
Research Support, American Recovery and Reinvestment Act
Research Support, N.I.H., Extramural
Research Support, N.I.H., Intramural
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Research Support, U.S. Gov't
Retracted Publication
Retraction of Publication
Scientific Integrity Review
Technical Report
Twin Study
Validation Study
Video-Audio Media
Webcast
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