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Impact simply reflects the ability of journals and editors to attract
the best papers available (E.Garfield, Institute for Scientific Information, Philadelphia)
Volker Fendrich, MD
Editor Assistant, BJS
Impact factor
• Citations to recent articles 1784 = 4.092 (BJS 2006) Number of recent articles 436
• Ability to predict citations is weak (Callaham JAMA 2002)
• The IF of the publishing journal determines the number of citations of the article (Callaham JAMA 2002)
Relationship between IF and the level of non-citation within surgical journals
Weale et al. BMC Med Res Methodol. 2004
15% of articles account for 50% of citations
Aims
• What makes highly cited papers special?
• Are there specific differences to Ann Surg?
• Is there a way to increase the IF of BJS?
The 50 top cited papers vs the 50 bottom cited (BJS 2000-05)
Top cited Bottom citedType of article 17 reviews
5 RCTs
28 original articles
0 reviews
2 RCTs
48 original articles
Country of origin 22 Countries (Netherlands 8, Scotland 7)
17 Countries
(England 17)
Discipline of first authour 98% surgeons 98% surgeons
Average citations since publication
80.8 0.8
Total citations since publication 4039 39
Cited in journals with higher IF (Ann Surg)
556 (127) 3 (1)
Cited in journals with lower IF 3233 31
Citations in BJS (% of all) 250 (6.2%) 5 (12.8%)
Topic: TOP or FLOP?
• Complications of radiofrequency coagulation of liver tumours
• Intra-anal and rectal application of L-erythro methoxamine gel increases anal resting pressure in healthy volunteers
• Randomized clinical trial of virtual reality simulation for laparoscopic skills training
• Operative mortality after colorectal resection in the Netherlands
• Value of POSSUM physiology scoring to assess outcome after intra-arterial thrombolysis for acute leg ischaemia
• Prognostic significance of the circumferential resection margin following total mesorectal excision for rectal cancer
Topic: Top or flop?• Complications of radiofrequency coagulation of liver tumours
• Intra-anal and rectal application of L-erythro methoxamine gel increases anal resting pressure in healthy volunteers
• Randomized clinical trial of virtual reality simulation for laparoscopic skills training
• Operative mortality after colorectal resection in the Netherlands
• Value of POSSUM physiology scoring to assess outcome after intra-arterial thrombolysis for acute leg ischaemia
• Prognostic significance of the circumferential resection margin following total mesorectal excision for rectal cancer
The competitors
Self Citations
2004
Self Citations
2005
Ann Surg 4.1% 7.8%
BJS 5.7% 5.0%
Top 20 reviews 2004/05 570 total citations 555 total citations
Impact factor Top 20 reviews
28.5 27.75
Main topics Totally mixed Totally mixed
Top 20 articles 2004/05 879 total citations 1911 total citations
Impact factor Top 20 articles
43.95 95.55
Main topics Colorectal cancer
(9/20)
Liver metastases (8/20)
What makes the difference?
Rising influence of China?
Chinese IF 2006: 3.23 (2004-05: 13 articles, 42 citations)
Chinese IF 2006: 3.25 (2004-05: 12 articles, 39 citations)
Note: Nearly 50% of all publications from Poon et al. University of Hong Kong
How to increase the IF?
• Self citations – unethical? (Sevinc 2004)
• Online availability (Murali et al 2004)
• Online survey to ask for desired topics
• Select authors on the basis of past performance