Contribution of case reports to glioblastoma research: systematic review and analysis of pattern of citation.
BACKGROUND
Research activity related to different aspects of diagnosis, epidemiology and treatment of glioblastoma has increased during recent years. Authors of scientific publications are able to choose between different formats including case reports. Little is known about their influence on advancement of the field or scientific merits. Do glioblastoma case reports attract attention or do they go largely unrecognized?


METHODS
Different measures of impact, visibility and quality of published research are available, each with its own pros and cons. For the present evaluation (to the best of our knowledge the first one on this subject), article citation rate was chosen. The databases PubMed and Scopus were searched for articles that were published during the 5-year time period between 2006 and 2010.


RESULTS
We identified 5831 articles dealing with glioblastoma. Of these, 286 (4.9%) reported on single patient cases and 15 (0.26%) were reports of two cases. The median number of citations was 1 (range 0-37). Stratified by year of publication, the median number ranged from 0 for those published in 2010 to 3 for those published in 2006. Citations appeared to gradually increase during the first 2-3 years after publication. As compared to other articles, case reports were significantly less likely to receive a large number of citations.


CONCLUSIONS
Compared to other formats, the proportion of case reports was limited and few of them were highly cited. It cannot be excluded that case reports without citation provide interesting information to some readers. However, their educational value is difficult to quantify.
Department of Oncology and Palliative Medicine, Nordland Hospital, Bodø, Norway. carsten.nieder@nlsh.no
Carsten
C
Nieder
Adam
A
Pawinski
Astrid
A
Dalhaug
D015706:Bibliometrics; D005909:Glioblastoma / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy; D006801:Humans; D011643:Publishing / Q000592:standards / Q000639:trends