The article contains a variety of links to PubMed, mostly in the citations. All of the articles referred to in this manner have DOIs, so it would be much preferable to link to them using these:

http://www.ncbi.nlm.nih.g...​870 is doi:10.1038/clpt.2012.42

http://www.ncbi.nlm.nih.g...​.fcgi?cmd=Retrieve&db=PubMed&dopt=Citati​on&list_uids=19279318 is doi:10.1177/1077558709332440

http://www.ncbi.nlm.nih.g...​.fcgi?cmd=Retrieve&db=PubMed&dopt=Citati​on&list_uids=18280787 is doi:10.1016/j.ijmedinf.2007.12.001

http://www.ncbi.nlm.nih.g...​990 is doi:10.1038/clpt.2011.83