The Impact Factor (IF): What Is It Good For? Richard M. Rocco, PhD October

A Student Challenge Find a clinical trial article in the medical literature on a drug or treatment protocol. Use that article for a class presentation or term paper. Blow the professor away, get an A. 2

The Problem Where to find the best article. Stack the odds in your favor with a high level clinical trial article. You have a better chance of getting to Chicago in a 2013 Lexus rather than a broken down 1983 Honda Civic with a bad transmission. 3

Hylauronic Acid Intra-articular Injections A few weeks ago some students were looking for a clinical trial article on hylauronic injections for a presentation. Finding articles on this subject is easy. Finding a high level article is a major challenge. 4

Google, hits 5

Google Scholar, hits 6

PubMed, 563 7

PubMed Clinical Trials, 188 8

New England J Medicine, 11 hits 9

How to Judge A High Level Clinical Trail Was power analysis used? How were random and systematic errors controlled for? What was the stopping rule? Was the odds ratio converted to risk? What is the width of the confidence interval? Was the follow-up sufficiently complete? What was the likelihood ratio at 95% CI? 10

Impact Factor (IF) In this presentation I will propose that the use of the IF in journal selection will increase the odds of obtaining a high level, evidence based clinical trial. 11

What is the Impact Factor (IF)? A statistical calculation introduced by Eugene Garfield at the Institute for Scientific Information (Thomson Reuters) in Impact factors range from 0 to over 50. The IF represents the number of times in a journal that an article is cited by other articles. If the article is good, others will use the data and cite it in their publications. 12

What the IF is Not. It is a surrogate marker, not a direct marker of journal quality. It is only an average measure of citation numbers. An IF of 3 means that the average number of citations received per paper published in the last two years in that journal was 3. Reviews, letters to the editor and editorials are not included in the calculations. 13

IF Ranking 8238 Science Journals Impact FactorNo. Journals% of Total < % 1.0 – % 2.1 – % 5.1– % 10.1 – % 20.1 – % 30.1 – > % % of science journals have an IF of less than 5.0

The IF for Nature for

NEJM, IF 53 A clinical trial published in a high IF journal will not guarantee a high level Lexus clinical trial but it will increase the odds greatly. A clinical trial published in a high IF journal will increase the odds that the trial will hold up to careful review and that it will contain a minimum of errors. The student can then focus on the importance of the clinical trial and not have to work around the weaknesses of the trial. 16

Journal Impact Factors (IF) Jorgensen, A., et al. Ann Rheum Dis 69: (2010)IF = 9.1 Mei-Dan, O., et al., JAPMA 100: (2010)IF =

ItemMei-Dan (2010)Jorgensen (2010) Placebo ControlledNoYes, saline injections RandomizedNoYes Drug1% sodium hyaluronate Dose/injection mg25 mg20 mg Frequency/week11 Number of weeks55 Anesthesia1% Lidocaine1% Lidocaine 0.5 mL Duration of study, weeks

ItemMei-Dan (2010)Jorgensen (2010) # Patients Power Analysis 15 No 335 Yes, 151/group Drug 165, placebo, 170 Informed Consentyes Blindednoyes, double blinded Age Range, years

ItemMei-Dan (2010)Jorgensen (2010) Exclusion criteria well defined Yes ADR reportedNoYes Treatment ComplianceNot givenDrug 99%, Placebo 95% Synovial fluid aspir.NoYes, to prevent drug dilution 20

ItemMei-Dan (2010)Jorgensen (2010) Follow-Up, weeks3252 Analgesics used during study All allowed, pill count not recorded. All drugs discontinued except for acetaminophen, pills counted. 21

ItemMei-Dan (2010)Jorgensen (2010) Main Outcome MeasureVisual Analog Scale Questionnaire Lequesne Algofunctional Index Score (LFI). # Questions611 questions Score Questionnaire administered weeks. 4,8,11,17, 32 22

ItemMei-Dan (2010)Jorgensen (2010) RESULTS:Visual Analog Scale Day Day p< All data mean, no SD given Responder Rates Hyal 67.9% Placebo 72.4% 23

Results Mei-Dan, O. (2010) 13 of 15 patients improved improvement by 20% in range of motion significant reduction in pain using the visual analog scale hyaluronate is a valid conservative treatment for…osteoarthritis 24

Results Jorgensen, A. et al. (2010) time to recurrence showed no significant treatment effect (p = 0.26) change from baseline pain showed no treatment effect acetaminophen consumption, global assessment, responder rates and adverse events, no significant difference hyaluronan is without clinical effect 25