PT - JOURNAL ARTICLE ED - , TI - P<sup>4</sup> Update AID - 10.3122/jabfm.2008.02.070272 DP - 2008 Mar 01 TA - The Journal of the American Board of Family Medicine PG - 173--174 VI - 21 IP - 2 4099 - http://www.jabfm.org/content/21/2/173.short 4100 - http://www.jabfm.org/content/21/2/173.full SO - J Am Board Fam Med2008 Mar 01; 21