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From impact factor to influence?. Kamran Abbasi Acting editor, BMJ. What I will talk about. What is impact factor? What is wrong with impact factor? What are the alternatives? What is influence? What does all this mean?. Citation rates.
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From impact factor to influence? Kamran Abbasi Acting editor, BMJ
What I will talk about • What is impact factor? • What is wrong with impact factor? • What are the alternatives? • What is influence? • What does all this mean?
Citation rates • The Institute of Scientific Information records scientific citations/references • The number of times a publication has been cited within a certain period • Published as the Science Citation Index
Impact factor • This is the mean citation rate of all articles contained in the journal • Published annually in the SCI Journal Citation reports
Definition of impact factor • The recorded number of citations within a certain year (eg 2003) to the items published in the journal during the preceding two years (eg 2001 and 2002) • Denominator: An “item” is a research paper or a review article • Numerator: Citations to all types of articles
Proper and improper uses of impact factor • Evaluating individual scientists • Awarding higher academic positions • Evaluating research groups • Evaluating institutions • Resource allocation • Evaluating journals
Some examples • In Japan people walk around boasting of their own individual impact factor • In the UK (and elsewhere) university funding is awarded on the basis of impact factors (research assessment exercise) • Deans instruct authors to publish in highest impact factors, though may not be the best fit
What I will talk about • What is impact factor? • What is wrong with impact factor? • What are the alternatives? • What is influence? • What does all this mean?
1 What is wrong with impact factors? • IF not statistically representative of of individual journal articles • IF correlates poorly with actual citations of individual articles • Authors not only use IF when submitting to journals • The ISI database is imperfect and contains citations to “non-citable” articles • Per Seglen BMJ 1997;314:497
2 What is wrong with impact factors? • Self citations are allowed • Review articles are heavily cited and inflate the impact factor • Long articles collect many citations • Short publication lag allows short term journal self citations • Same language citations are preferred by authors
3 What is wrong with impact factors? • Selective journal self citation • Coverage of the database is not complete (3,200 out of 126,000 journals) • Database has an English language bias • Database is dominated by American publications • Journals in database may vary from year to year • IF is a function of the number of articles in the research field
4 What is wrong with impact factors? • Research fields with literature that rapidly becomes obsolete are favoured • Impact factor depends on expansion or contraction of research field • Small research fields lack journals with high impact • Relations between fields (eg clinical v basic science) strongly determine IF • Citation rate of article determines journal impact, but not vice versa
What I will talk about • What is impact factor? • What is wrong with impact factor? • What are the alternatives? • What is influence? • What does all this mean?
“The combined shortfall of university funding has forced deans of medical schools to behave like managers of Premier Division soccer clubs, recruiting potential stars . . .at the expense of teaching and clinical practice”Banatvala et al Lancet 2005;365:458-9
1 What are the alternatives? • Will papers from high impact factor journals be cited in evidence based guidance? • Yes there is a correlation but papers from journals with low impact factor are also cited frequently • Nakayama JAMA 2004;290:755-6 • Might citations in evidence based guidelines be a better clinical measure?
2 What are the alternatives? • A patient citation index • Proposed by Martin Rosser, editor of JNNP, and by Mary Baker and Matthew Menken from BMJ’s patient advisory board • A fuzzy idea but the gist that patients would rate articles of importance to them and hence of greater clinical importance
3 What are the alternatives? • The Leiden University system • This is a method of measuring academic achievement through monitoring mentions of an article in the media, in parliament, and other such markers of “influence” • It requires a lot of work but may be fairer
4 What are the alternatives—from rapid responses on bmj.com • User rating of articles • Use a longer term base than 2 years • Exclude letters and reviews to focus on research • “Scope adjusted impact factor” • Expert evaluation of best papers • Many from Steve Harnad around citations, downloads, and google type page ranks • Faculty of 1000 assessment www.f1000.com • Ask clinicians
What I will talk about • What is impact factor? • What is wrong with impact factor? • What are the alternatives? • What is influence? • What does all this mean?
Why do we care about influence? • The mission of the BMJ Publishing Group has two parts • INFLUENCE: To serve the needs of doctors and others, to influence the international debate on health • PROFIT: to make enough money to support the mission of influence
Why do we care about influence? • Profit is easily measured—down to the last penny • We are not quite sure what influence is, which makes it hard to measure • Yet influence is the first part of our mission and profit the second • We mustn’t allow the important to be displaced by the measurable
Definitions of influence • “The power of producing an effect, especially unobtrusively” Chambers dictionary • (Mark Twain said: “If you don’t mind who gets the credit you can do anything.”) • Influence is in some ways a polite word for power. • Influence is also something to do with brand. A stronger brand=more influence.
What is influence? • Level one: something changes because of what we have published • Doctors change what they do. • Ministers change policy. • WHO decides to do things differently. • Drugs are prescribed more or less. • New techniques or methods are adopted. Old ones are abandoned.
What is influence? • Written information on its own rarely leads to change • “All journals do is take in other people’s washing” • This sort of influence is probably rare and is hard to identify. • Many different factors usually contribute to a particular change: so even if something we published contributed it could not be described as the cause.
Examples of change caused by research articles I • Photodynamic therapy with a new drug might cause severe burns • Hettiaratchy S, Clarke J, Taubel J, Besa C. Burns after photodynamic therapy. BMJ 2000; 320: 1245
Examples of change caused by research articles II • The use of albumin in critically ill patients may be dangerous • Cochrane Injuries Group Albumin Reviewers. Human albumin administration in critically ill patients: a systematic review of randomised controlled trials. BMJ 1998; 317: 235-240
Examples of change caused by research articles III • Minocycline should not be used as the first line treatment of acne • Made the front page of the Daily Mail, which might be Britain’s most influential newspaper • Gough A, Chapman S, Wagstaff K, Emery P, Elias E. Minocycline induced autoimmune hepatitis and systemic lupus erythematosus-like syndrome. BMJ 1996;312:169-72
What is influence? • Level two: setting an agenda or legitimising an issue • Examples of where the BMJ might have done this, at least in Britain • Evidence based medicine • Inequalities in health • Prison health care • Medical error • Doctors and the drug industry
What is influence? • Level three: leading by example and being folowed • Possible examples • bmj.com is free • open peer review • BMJ ethics committee • rapid responses on bmj.com • collected resources on bmj.com • BMJ patient advisory group
What is influence? • Level four: being quoted/cited • “The only thing worse than being talked about is not being talked about.” Oscar Wilde
What is influence? • Where might you be quoted? • Other journals (impact factor) • Cochrane reviews • Guidelines • Mass media • Parliament (Hansard) • Evidence Based Medicine/Journalwatch • Important policy documents (for example, Institute of Medicine report) • Presentations
What is influence? • Level five: being paid attention to • Readership (preferably judged by others) • Website hits (in a week or over time) • Sales
What is influence? • Level six: being known about • Widely known even if not quoted or read among international health professionals, political leaders, the public • If George Bush knows about you that’s more influential than if your mum does—sadly
Scoring influence the Richard Smith way • Level one: creating change • Several clear cases 5 points • One case 3 points • Level two: setting agendas and legitimising issues • Several cases 5 points • One case 3 points