Bibliometrics of the Periodontal Literature From 1995 to 2010

0

25

50

75

100

40.7 35.526.8 27.6

43.638.5

39.8 31.0

1.7

2.4

1.1

1.3

12.620.2

23.730.1

0.20.2

0.2 0.2

1.2 3.2 8.3 9.9

1995 2000 2005 2010

ABSTRACTBackgroundBibliometrics provides important information to support evidence-based research policies. The aim of this study was to investigate the bibliometrics of periodontal literature, assessing: the geographical origin, study design and topic investigated in periodontal research published during 1995-2010. Three null hypotheses were investigated in this study: 1) that there is no difference in the average number of authors per paper in the years 1995 to

2010;2) that there is no difference in the percentage of manuscripts, out of the total published

number, originating from North America, Europe, South America and Asia in the years 1995 to 2010;

3) that there is no difference in the topic investigated by the studies published in the years 1995 to 2010.

MethodsArticles published in the five major periodontal journals during 1995-2010 were retrieved through hand search.The following articles were excluded: abstracts of meetings, letters to the editor/author, journal watch, editorial, errata corrige, reprints, articles with no author mentioned, meeting compendium and academy/association guidelines.The following variables were extrapolated from each article: number of authors, study design, topic investigated, financial support, and geographical origin. General linear model assessed the influence of independent variables on number of authors per article. Chi-square test assessed the statistical difference of the variables during years 1995-2010.

Results2260 articles were reviewed, 2076 met the inclusion criteria.The number of authors per article increased (p<0.001) from 4.0 (1995) to 5.1 (2010). The proportion of articles published from North America and Europe decreased (p<0.0001) from 84.3% (1995) to 58.6% (2010), while for Asia and South America increased (p<0.0001) from 13.8% (1995) to 40% (2010). Research targeting prevention and treatment of periodontal disease is decreasing (p<0.0001) in favor of implant-related research. Governmental research funding is increasing (p<0.0001).

ConclusionsPeriodontal research changed significantly during the last 15 years.Within the limitations of this study it can be concluded that:The average number of authors, per publication, significantly increased from 1995 to 2010.The proportion of periodontal research originating from North America and Europe has decreased, while periodontal research from South America and Asia has increased.The focus of the research is shifting from prevention and treatment of periodontal disease to implant-related procedures. Scholarly production in the field of implant dentistry has dramatically increased in the same time periods, assuming an ever greater role in periodontal research.

Current trends may require scientific journals to adapt publication policies. Entities financing research may decide to increase the support for

periodontal disease-related research.

Alessandro Geminiani, DDS, MSc, MS Changyong Feng, PhD Jack G Caton, DDS, MS Carlo Ercoli, DDS

Eastman Institute for Oral Health, University of Rochester, NY

PAST NOW

1995 2000 2005 2010

1997 New ICMJE Guidelines

Authorship InformationGeographical Origin

Design - Longitudinal, Cross-sectional, RCT in vitro Topic - Perio, Implants, Mucogingival

Funding - Self, Private, Government

3.549 Impact Factor3.027 2.192 1.9661.702

Total # of publications in YearTotal # of publications in YearTotal # of publications in YearTotal # of publications in YearTotal # of publications in Year

Journal 1995 2000 2005 2010 Total

JCP 139 137 192 133 601

P2000 31 39 28 39 137

J Perio 143 231 271 211 856

JPR 60 44 66 107 277

IJPRD 40 53 54 58 205

2076

Fulltext Hand Search, Two Investigators

Material and Methods

Material and Methods

Independent variables p-valueYEAR <0.0001JOURNAL <0.0001LOCATION <0.0001YEAR*JOURNAL 0.06YEAR*LOCATION 0.03JOURNAL*LOCATION 0.002

Results

A summary of general linear model (GLM) for testing main and interaction effects for independent variables as contributing factors to

number of authors per article

Chi-square test reported a significant difference for the comparisons of the following variables: geographic origin of the article (p<0.0001); type of study (p<0.01); financial support of study (p<0.0001); and topic of the

study (p<0.0001).

1

2

3

4

5

6

4.04.4 4.6

5.1

1995 2000 2005 2010# authors

Average number of Authors

North America Europe OceaniaAsia Africa South America

Publications per Country

Periodontal Disease Mucogingival SurgeryDental Implants Other

0

25

50

75

100

57.6 53.4 51.4 47.6

1.2 5.6 4.3 6.26.5 11.5 11.5 20.4

34.6 29.6 32.9 25.7

1995 2000 2005 2010

ResultsPublications per Topic

Periodontal research changed significantly during the last 15 years. Within the limitations of this study it can be concluded that:

• The average number of authors, per publication, significantly increased from 1995 to 2010.

• The proportion of periodontal research originating from North America and Europe has decreased, while periodontal research from South America and Asia has increased.

• The focus of the research is shifting from prevention and treatment of periodontal disease to implant-related procedures.

Current trends may require scientific journals to adapt publication policies.

Entities financing research may decide to increase the support for periodontal disease-related research.

Conclusions

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