The authors assess the number of coauthors in articles published by authors affiliated with domestic (Croatian) and foreign (non-Croatian) institutions in the Croatian Medical Journal (CMJ) and investigate the increase in the number of coauthors after inclusion of the journal in the Current Contents (CC) bibliographic database (Thomson ISI, Philadelphia, PA) in 1999. They analyzed 761 articles published in the CMJ between 1992 and 2003, and determined the average number of authors per article, authors' country of origin, and the gross domestic product (GDP) per capita of the authors' country. The average number of authors in articles written by authors affiliated with domestic institutions was significantly larger in almost all journal sections. The increase in the number of domestic coauthors was more pronounced after inclusion of the journal in the CC database. The number of domestic coauthors published in the Clinical section increased from 4.2 ± 2.1 to 5.1 ± 2.3. There was also an increase in coauthors published in the Public Health section—from 3.1 ± 1.9 to 4.1 ± 1.9. The results of the study imply that authors' adherence to the International Committee of Medical Journal Editors (ICMJE) authorship criteria depends on the size of the scientific community and that adherence is poor among domestic authors publishing in a small, national medical journal outside of mainstream science. An increased number of coauthors in articles published by authors affiliated with domestic institutions does not necessarily imply authorship misconduct but it suggests involvement of an appreciable number of authors who made few or no substantial contributions to the research. This discounts two main purposes of scientific authorship: to confer credit and denote responsibility for performed research.