http://dx.doi.org/10.1136/bjsm.2005.025270 | | | | DOI Link |
http://bjsm.bmj.com/content/40/3/193.full | 10/21/2014 | | Item is within a limited-access website | |
http://bjsm.bmj.com/content/40/3/193.full.pdf | 10/21/2014 | PDF Reader | Item is within a limited-access website | |