Differences between h-index measures from different bibliographic sources and search engines.

OBJECTIVE To analyze the use of the h-index as a measure of the bibliometric impact of Brazilian researchers' scientific publications. METHODS The scientific production of Brazilian CNPq 1-A researchers in the areas of public health, immunology and medicine were compared. The mean h-index of the groups of researchers in each area were estimated and nonparametric Kruskal Wallis test and multiple comparisons Behrens-Fisher test were used to compare the differences. RESULTS The h-index means were higher in the area of Immunology than in Public Health and Medicine when the Web of Science base was used. However, this difference disappears when the comparison is made using Scopus or Google Scholar. CONCLUSIONS The emergence of Google Scholar brings a new level to discussions on the measure of the bibliometric impact of scientific publications. Areas with strong professional components, in which knowledge is produced and must also be published in the native language, vis-a-vis its dissemination to the international community, necessarily have a standard of scientific publications and citations different from areas exclusively or predominantly academic and they are best captured by Google Scholar.