JCO’s Impact Factor Increases to 10.9

JCO is pleased to announce that its impact factor for 2003 has increased to 10.9. JCO’s 2002 impact factor was 9.9. This 10 percent increase reflects JCO’s continued success in serving the clinical oncology community by providing the most important and timely peer reviewed research available. JCO’s 2003 impact factor ranks it number 5 out of 115 oncology journals worldwide as ranked by the Institute for Scientific Information (ISI). Impact factors and journal rankings are calculated yearly by the ISI, which is part of the Thomson Corporation.

Journal	Rank	2003 Total Cites	Impact Factor	Immediacy Index	2003 Articles	Cited Half-Life
JCO	5	45,857	10.864	1.677	643	5.0

Journal Impact factor is one measure of a journal’s reach and relative importance in the scientific community. Other factors include total readership, frequency, number of editorial pages, and strength of editorial board. JCO is a leader in all these categories.

Impact factor is a measure of the frequency with which the "average article" in a journal has been cited in a particular year. For example, JCO’s 2003 impact factor of 10.864 means that JCO articles published in 2001 or 2002 were cited in 2003 an average of over 10 times each. ISI calculates impact factor by dividing the number of current citations received to articles published in the previous two years by the total number of citable articles in those two years. ISI defines citable articles as original articles, review articles, case reports, and articles in symposium supplements. ISI does not count the following article types: letters, editorials, commentaries, and abstracts.

Other useful measures of JCO’s importance and reach include cited half-life and immediacy index.

Cited half-life is a measure of the general staying power of research or how long research continues to be cited in the scientific literature. It represents the number of publication years from the current year that account for 50 percent of the current citations received. JCO’s 2003 cited half-life of 5.0 means that 50 percent of the citations received in 2003 were from articles published from 1998 – 2002. JCO’s cited half-life places it solidly with other research journals in the oncology category and is an indication of the durability of JCO research.

Immediacy index is a measure of the current level of interest in a journal’s research or how "hot" the research is. Immediacy index reports the number of times an article published in a certain year is cited in that same year. JCO’s 2003 immediacy index of 1.677 indicates that the average JCO article published in 2003 was cited more than one and a half times that same year. JCO’s immediacy index is competitive with similar journals in the oncology category.