How open access is your research area?


Using PubMed’s "Limits" tab, it is easy to filter searches by
date of publication, and also by whether an article has a link to an
online full text, and whether that online full text is freely available.

handy side effect of this is that it is possible to search PubMed for
articles in the last 60 days, and to calculate an Open Access Quotient to quantify just how open a
particular research field is – i.e. what fraction of the research in that
area is available with open access immediately following publication.

The OAQ for PubMed as a whole currently stands at 6.8%, but this overall figure conceals major variation between fields.


Is there a research area with a higher Open Access Quotient than malaria? Why not help us find out?

We’ll send an "I’m Open" BioMed Central T-shirt to whoever can identify the biomedical field with the highest Open Access Quotient (and we’d also be interested to know what fields seem to have the lowest).

To qualify, a PubMed Search should be based on conceptual keywords (not author or journal names) and should return at least 100 articles which have online fulltexts published in the last 60 days

Send your findings to, or post them as comments to this blog item.


Enter one or more keywords in the box below to calculate OAQ for a given topic:

[Thanks Alf!]

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matthew hankins

“Is there a research area with a higher Open Access Quotient than malaria?”

The answer to this question should surely take into account the 95% confidence intervals around the estimated OA quotients.

For the figures quoted, these are:

malaria 19.8 (16.1,24.2)
microarray 16.9 (14.6,19.5)
genomic 12.9 (11.9,14.1)
influenza 12.3 (9.3,16.1)
AIDS 11.3 (8.7,14.5)
cancer 7.2 (6.7,7.8)
cardiovascular 5.0 (4.2,5.8)
clinical trial 4.0 (3.2,4.9)

I’ll accept a T-shirt for adding scientific rigour to the decision process…

matthew hankins

Family medicine is looking good:

Open Access: 48
Total: 104
Open Access Quotient: 46.15% 95% CL: (36.88,55.70)

heather piwowar

What fun! Thanks to Alf’s tool, here are a few interesting ones I found.

* Open Access: 126
* Total: 3964
* Open Access Quotient: 3.18%

computational biology
* Open Access: 131
* Total: 171
* Open Access Quotient: 76.61%

A few others:
sequence alignment
* Open Access: 120
* Total: 656
* Open Access Quotient: 18.29%

(contrast to “cancer” above)
* Open Access: 111
* Total: 2187
* Open Access Quotient: 5.08%

(so close! maybe rerun it tomorrow? 🙂 )
* Open Access: 96
* Total: 495
* Open Access Quotient: 19.39%

sequence alignment
(doesn’t make the cut, but wow!)
* Open Access: 51
* Total: 153
* Open Access Quotient: 33.33%

A thought: if the minimum article threshold were for the total number of articles, rather than the number which are open, the overall size of the research areas could be more similar for both the high and low quotients.

Thanks for highlighting this interesting and important topic.


heather piwowar

A few more:

* Open Access: 155
* Total: 355
* Open Access Quotient: 43.66%

* Open Access: 196
* Total: 829
* Open Access Quotient: 23.64%

sequence database
* Open Access: 114
* Total: 258
* Open Access Quotient: 44.19%

* Open Access: 128
* Total: 2719
* Open Access Quotient: 4.71%

* Open Access: 98
* Total: 1902
* Open Access Quotient: 5.15%


christina peterson

In fact, neurology in general fares rather poorly.

* Open Access: 78
* Total: 1287
* Open Access Quotient: 6.06%
* Open Access: 36
* Total: 588
* Open Access Quotient: 6.12%
* Open Access: 7
* Total: 176
* Open Access Quotient: 3.98%
* Open Access: 5
* Total: 111
* Open Access Quotient: 4.5%
* Open Access: 15
* Total: 334
* Open Access Quotient: 4.49%
* Open Access: 30
* Total: 587
* Open Access Quotient: 5.11%
* Open Access: 17
* Total: 317
* Open Access Quotient: 5.36%