Science and Engineering Ethics

, Volume 18, Issue 2, pp 223–239 | Cite as

Prevalence of Plagiarism in Recent Submissions to the Croatian Medical Journal

  • Ksenija BaždarićEmail author
  • Lidija Bilić-Zulle
  • Gordana Brumini
  • Mladen Petrovečki
Original Paper


To assess the prevalence of plagiarism in manuscripts submitted for publication in the Croatian Medical Journal (CMJ). All manuscripts submitted in 2009–2010 were analyzed using plagiarism detection software: eTBLAST, CrossCheck, and WCopyfind. Plagiarism was suspected in manuscripts with more than 10% of the text derived from other sources. These manuscripts were checked against the Déjà vu database and manually verified by investigators. Of 754 submitted manuscripts, 105 (14%) were identified by the software as suspicious of plagiarism. Manual verification confirmed that 85 (11%) manuscripts were plagiarized: 63 (8%) were true plagiarism and 22 (3%) were self-plagiarism. Plagiarized manuscripts were mostly submitted from China (21%), Croatia (14%), and Turkey (19%). There was no significant difference in the text similarity rate between plagiarized and self-plagiarized manuscripts (25% [95% CI 22–27%] vs. 28% [95% CI 20–33%]; U = 645.50; P = 0.634). Differences in text similarity rate were found between various sections of self-plagiarized manuscripts (H = 12.65, P = 0.013). The plagiarism rate in the Materials and Methods (61% (95% CI 41–68%) was higher than in the Results (23% [95% CI 17–36%], U = 33.50; P = 0.009) or Discussion (25.5 [95% CI 15–35%]; U = 57.50; P < 0.001) sections. Three authors were identified in the Déjà vu database. Plagiarism detection software combined with manual verification may be used to detect plagiarized manuscripts and prevent their publication. The prevalence of plagiarized manuscripts submitted to the CMJ, a journal dedicated to promoting research integrity, was 11% in the 2-year period 2009–2010.


Research Ethics Peer review Plagiarism Self-plagiarism Scientific misconduct Research integrity Software 



Croatian Medical Journal


Committee on Publication Ethics



The authors wish to thank Ana Marušić and Ivan Damjanov (editors-in-chief during the 2009–2011), Matko Marušić (founder and editor emeritus), Vedran Katavić, Dario Sambunjak and Vesna Kušec (editorial board members during the 2009–2011) from the Croatian Medical Journal, Aleksandra Mišak (translator) and Elizabeth Wager (COPE).


The study is part of the scientific project “Prevalence and attitude towards plagiarism” (No. 062-0000000-3552) supported by the Croatian Ministry of Science, Education, and Sports and project “Prevalence and attitudes towards plagiarism in biomedical publishing” supported by the Committee on Publication Ethics (COPE).

Conflict of interest

The authors declare that they have no conflict of interests.


  1. Bilic-Zulle, L. (2010). Responsible writing in science. Biochemia Medica, 20(3), 279–281.Google Scholar
  2. Bilic-Zulle, L., Azman, J., Frkovic, V., & Petrovecki, M. (2008). Is there an effective approach to deterring students from plagiarizing? Science and Engineering Ethics, 14(1), 139–147.CrossRefGoogle Scholar
  3. Bilić-Zulle, L., Frković, V., Turk, T., Ažman, J., & Petrovečki, M. (2005). Prevalence of plagiarism among medical students. Croatian Medical Journal, 45(1), 126–131.Google Scholar
  4. Bloomfield, L. (2004). WCopyfind program instructions. Accessed 7 September 2011.
  5. Braumoeller, B. F., & Gaines, B. J. (2001). Actions do speak louder than words: Deterring plagiarism with the use of plagiarism detection software. Political Science and Politics, 34(4), 835–839.CrossRefGoogle Scholar
  6. British Medical Journal. (n.d.). Redundant publication. Accessed 12 July 2011.
  7. Butler, D. (2010). Journals step up plagiarism policing. Nature, 466, 167. doi: 10.1038/466167a.CrossRefGoogle Scholar
  8. COPE. (2006). COPE flowchart. . Accessed 4 July 2011.
  9. Croatian Medical Journal. Guidelines for authors: Manuscript preparation and submission. Accessed 4 July 2011.
  10. CrossCheck. CrossCheck. Accessed 14 July 2011.
  11. Errami, M., Wren, J. D., Hicks, J. M., & Garner, H. R. (2007). eTBLAST: A web server to identify expert reviewers, appropriate journals and similar publications. Nucleic Acids Research. doi:10.193/nar/gkm221.
  12. Errami, M., Zhaohui, S., Long, T. C., George, A. C., & Garner, H. R. (2009). Déjà vu: A database of highly similar citations in the scientific literature. Nucleic Acids Research. doi: 10.1093/nar/gkn546.
  13. Fisher, B. A., & Zigmond, M. J. (2011). Educational approaches for discouraging plagiarism. Urology and Oncology, 29(1), 100–103.CrossRefGoogle Scholar
  14. Garner, H. R. (2011). Combating unethical publications with plagiarism detection services. Urology and Oncology, 29(1), 95–99.CrossRefGoogle Scholar
  15. Hayes, N., & Introna, L. D. (2005). Cultural values, plagiarism and fairness: When plagiarism gets in the way of learning. Ethics and Behavior, 15(3), 213–231.CrossRefGoogle Scholar
  16. Hrabak, M., Vujaklija, A., Vodopivec, I., Hren, D., Marušić, M., & Marušić, A. (2004). Academic misconduct among medical students in a post-communist country. Medical Education, 38, 276–285.CrossRefGoogle Scholar
  17. Kerans, M. E., & Jager, M. (2010). Handling plagiarism at the manuscript editor’s desk. European Science Editing, 36(3), 62–65.Google Scholar
  18. Magnus, J. R., Polterovich, V. M., Danilov, D. L., & Savvateev, A. V. (2002). Tolerance of cheating: An analysis across countries. The Journal of Economic Education, 33(2), 125–135.CrossRefGoogle Scholar
  19. Marusic, A. (2010). Editors as gatekeepers of responsible science. Biochemia Medica, 20(3), 282–287.Google Scholar
  20. Mason, R. (2009). Plagiarism in scientific publications. Journal of Infections Developing Countries, 3(1), 1–4. Accessed 15 July 2011.
  21. Mavrinac, M., Brumini, G., Bilić-Zulle, L., & Petrovečki, M. (2010). Construction and validation of attitudes toward plagiarism questionnaire. Croatian Medical Journal, 51(3), 195–201.CrossRefGoogle Scholar
  22. ORI. (2000). Office of the President, Office of Science and Technology Policy: Federal research misconduct policy. Federal Register, 65, 76260–76264. Accessed 7 September 2011.
  23. Petrovečki, M., & Scheetz, M. D. (2001). Croatian medical journal introduces culture, control, and the study of research integrity. Croatian Medical Journal, 42(1), 7–13.Google Scholar
  24. Pupovac, V., Bilic-Zulle, L., Mavrinac, M., & Petrovecki, M. (2010). Attitudes toward plagiarism among pharmacy and medical biochemistry students—Cross-sectional survey study. Biochemia Medica, 20(3), 307–313.Google Scholar
  25. Roig, M. (2009). Plagiarism: Consider the context. Science, 325(5942), 813–814.CrossRefGoogle Scholar
  26. Roig, M. (2010). Plagiarism and self-plagiarism: What every author should know. Biochemia Medica, 20(3), 295–300.Google Scholar
  27. Segal, S., Gelfand, B. J., Hurwitz, S., Berkowitz, L., Ashley, S. W., Nadel, E. S., et al. (2010). Plagiarism in residency application essays. Annals of Internal Medicine, 153(2), 112–120.Google Scholar
  28. Sorokina, D., Gehrke, J., Warner, S., & Ginsparg, P. (2006). Plagiarsim detection in arXiv. In Proceedings of ICDM (pp. 1070–1075). Accessed 12 July 2011.
  29. Sun, Z., Errami, M., Long, T., Renard, C., Choradia, N., & Garner, H. (2010). Systematic characterizations of text similarity in full text biomedical publications. Plos One. doi: 10.1371/journal.pone.0012704.
  30. Wager, E. (2011). How should editors respond to plagiarism? COPE discussion paper. Accessed 12 September 2011.
  31. Wager, E., Fiack, S., Graf, C., Robinson, A., & Rowlands, I. (2009). Science journal editors’ views on publication ethics: Results of an international survey. Journal of Medical Ethics, 35(6), 348–353.CrossRefGoogle Scholar
  32. Zhang, H. (2010). CrossCheck: An effective tool for detecting plagiarism. Learned Publishing, 23(1), 9–14.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Ksenija Baždarić
    • 1
    Email author
  • Lidija Bilić-Zulle
    • 1
    • 2
  • Gordana Brumini
    • 1
  • Mladen Petrovečki
    • 1
    • 3
  1. 1.Department of Medical InformaticsRijeka University School of MedicineRijekaCroatia
  2. 2.Clinical Department of Laboratory DiagnosticsClinical Hospital Centre RijekaRijekaCroatia
  3. 3.Department of Clinical Laboratory DiagnosticsDubrava Clinical HospitalZagrebCroatia

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