Links from PubMed (nlm.nih.gov) not appearing in backlinks for articles

[aafpitadmin]

Content from our medical journals gets indexed by the National Library of Medicine / PubMed on a monthly basis. The link to the full article appears in the upper-right corner on PubMed, yet I'm unable to find PubMed (nlm.nih.gov) backlinks in the reporting tools.

Example:
Article Title: Respiratory Syncytial Virus Infection in Children (allintitle query)
Article URL: http://www.aafp.org/afp/2011/0115/p141.html
PubMed URL: http://www.ncbi.nlm.nih.gov/pubmed/21243988

The PubMed link is to http://www.aafp.org/link_out?pmid=21243988 ,
a 301 redirect to the article, http://www.aafp.org/afp/2011/0115/p141.html

Any idea why this link isn't appearing in backlinks? This isn't just for one article, we have roughly 2,000 articles from 1998 to the present. Articles from the past 12-months are access-restricted, and after 12-months the articles become public.

[aafpitadmin]

I feel very silly for posting this question.

Looking at the Pubmed source:

Doh!

[Host1]

The reason for this is most likely the use of a "out-link" with 301 redirect. Not 100% sure, but i would assume this is the reason for it not appearing in backlinks.