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Background and Aim: Using Hirsch index as an important tool to describe the scientific outputs of researchers has caused some authors to increase their self-imposed parameters, increase, citing themselves. Therefore it is necessary to consider the effect of self-citation on Hirsch index for every author to have better measuring on the quality of researchers scientific production.

Materials and Methods: This research is descriptive method of citation analysis in general and specifically self-citation analysis. The study, are Iranian prolific authors in the field of medicine that have at least 30 documents indexed in Web of Science database between 2004 to 2006. Citations following up was studied till December 2010 Results was analysis using Excel software version 2007.

Results: The average self-citation observed between prolific authors in medical field was 25/89 percent. Hirsch index for 30/77 percent of authors had changed considerably. The authors rating scheme based on Hirsch index was done after removing self - citation so that 38/46 percent of authors decreased to lower level.

Conclusion: Considering that 10 to 30 percent of self-citation can be normal and justified, the status of self-citatin of Iranian prolific authors in medical field is desirable. Also, lower rates of self - citation of these authors doesnot affect Hirsch index.

Background and Aim: Self-citation, as one of the limitations of citation analysis, unusually affects the ranking of journals. This study aims to evaluate the degree of relationship between self-citation and immediacy index correlation of Iranian medical journals indexed in Scopus Citation Index between 2005 and 2009.

Materials and Methods: The method of the study is survey-descriptive in which citation analysis is used. The study included all Iran-based English medical journals indexed in Scopus database up to May 2009. The control list was prepared and its validity was confirmed. Data were collected by referring to Scopus website and publication review resources, and analyzed by statistical software and appropriate methods.

Results: The findings showed that self-citation rate of journals was 29.64 percent, which comprised 14.43 percent of the total number of citations. There was a significant relationship (at the level of 0.01) between self-citation rate and immediacy index of journals (p = 0.591). Besides, Pearson correlation coefficient showed a significant relationship between the number of journals' articles and the journals' immediacy indexes excluding self-citation during the years of study.

Conclusion: Self-citation has a direct effect on journals' immediacy index that is, an increase in the rate of self-citation causes an artificial increase in the journals' immediacy index. On the other hand, immediacy index is affected by the number of journal articles. Therefore, the reduction or elimination of self-citation seems to be necessary for the journals and can put them in their right place.

Background and Aim: Citation is one of the journals ranking factors. Self-Citation rates regarding journals `performance, especially in international databases, is important. The aim of this study is to examine the effect of Journal self-Citation on Impact Factor of Iranian English medical journals indexed in the Web of Science and Islamic World Science Citation Center.

Materials and Methods: The Impact Factor of 12 journals in WoS and 26 in ISC were studied during years 2006-2009 using citation analysis and Journal self-Citation. Self-Citation rate were calculated using cited journals and citing journals tables in ISC. Wilcoxon test and Mann-whiteny test were used for comparison of self-citation rate between two databases. In order to determine any correlation between journal self-citation and IF in WoS, Pearson test was used. In ISC, Spearman test was performed. For comparison of two correlations test, Covariance test was used.

Results: No significant difference between Journal self-citation rates in two databases was noted(p>0.05).There was a significant correlation between Journal self-citation and Impact Factor in WoS(p=0.007, r=0.64). The correlation was not statistically significant in ISC(p>0.05, rsp =0.23). There was not any significant difference between the relations of Journal self-citation and impact factor in two databases(p=0.526).

Conclusion: Attention to the Journal self-citation rates for comparison of Journal Impact Factor in WoS is more important than attention to the comparison of these journals between two Databases.