Tuesday, April 20, 2010

Journal Impact Factors

Candid Engineer has a post on impact factors. I find the variability of impact factors by field quite frustrating as it often neglects the field specific differences in publication style. Take, for example, the field of statistics. I have yet to find a statistician who would not be proud of an article in the Journal of the American Statistical Society (JASA). It has an impact factor of 2.3; this does not compare favorably with (for example) Epidemiology (IF=5.4) which also publishes methodological papers. But the impact factor approach understates the effort required to beuild on or develop methods -- more sophisiticated methods take a lot longer to work their way into the literature.

In any case, comparing JASA to the New England Journal of Medicine (IF=50!!) makes it clear that the field has a lot to do with the impact of a journal.

So what do you do when you are on the borders of a field?

It's a tricky problem . . .


  1. In Oz the NHMRC has published a policy document saying that they will no longer accept IF as a measure of quality.

    All journals have now been given a reputation score inside their fields (A* A B C).

    So NEJM is an A*, clearly, but so is the JASA and Epidemiology

  2. That's pretty interesting. I spoke to a french researcher who used a similar scale, although it gave zero weight to papers published in journals below the median in imapct for a field.

    I'd like to give these papers some weight other than zero . . .

    Is the Australian system different in this regard?

  3. It's very new. So it's hard to say. But it does focus you on getting something into that next tier.

    Having said that the tiers are very broad. The A* tier in medicine, for instance, includes the NEJM at the top and good quality specialist journals toward the bottom, like Thorax.

    Whether or not any of that is actually taken seriously in peer review is another matter. We shall see.

  4. Sorry. As to your question about scoring papers as a zero. If the journal isn't somehow in the list then I guess it would score zero.