title: Authorship characteristics in prosthodontic literature: proliferation and internationalization. A review and analysis following a 10-year observation.
abstract: BACKGROUND
  Author characteristics and the extent of dental literature authorship globalization have not been widely investigated, especially in prosthodontics.
  
  
  OBJECTIVE
  The purpose of this study was to examine trends in authorship characteristics in prosthodontics.
  
  
  METHODS
  Articles published in The Journal of Prosthetic Dentistry (JPD), International Journal of Prosthodontics (IJP), and Journal of Prosthodontics (JP) in 1998, 2003, and 2008 were reviewed. Abstracts, letters to the editor, and book reviews were not included in the investigation. The authors' educational degrees had to be listed in the publications for the articles to be included. For each article, number of authors, degrees of all authors, academic ranks of first and last authors, and geographic origin were recorded. Descriptive and analytic analyses (alpha=.05), including a generalized linear model, Kruskal-Wallis, Mann-Whitney U, or chi-square tests, were used as appropriate.
  
  
  RESULTS
  A total of 998 articles met the inclusion criteria from the 3 selected journals for the years studied. Across all 3 journals, the mean number of authors per article increased significantly from 2.9 in 1998 to 3.6 in 2008 (Kruskal-Wallis, P<.001). The mean number of authors per article increased steadily on all continents, except for Africa and Oceania. A steady increase of authors with higher degrees was observed. There was a significant increase in the proportion of senior-ranking faculty as last author over time (chi-square=5.57, df=1, P=.018). The contributions from Asia and South America increased over time.
  
  
  CONCLUSIONS
  The number of authors per article, the number of authors with higher educational degrees, and the percentage of senior-ranking faculty as last author steadily increased in the prosthodontic literature from 1998 to 2008. The trend of globalization of authorship was evident in the prosthodontic literature.
authors.affiliation: Department of Restorative Dentistry, College of Dentistry, University of Illinois at Chicago, Chicago, IL 60612-7211, USA.
authors.forename: Judy Chia-Chun
authors.initials: JC
authors.lastname: Yuan
authors.forename: Damian J
authors.initials: DJ
authors.lastname: Lee
authors.forename: Kent L
authors.initials: KL
authors.lastname: Knoernschild
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Campbell
authors.forename: Cortino
authors.initials: C
authors.lastname: Sukotjo
mesh_terms: D001319:Authorship; D015706:Bibliometrics; D016009:Chi-Square Distribution; D004522:Educational Status; D005179:Faculty, Dental; D006801:Humans; D038622:Internationality; D016014:Linear Models; D010506:Periodicals as Topic / Q000706:statistics & numerical data*; D011365:Professional Practice Location / Q000706:statistics & numerical data; D011476:Prosthodontics; D018709:Statistics, Nonparametric