PT - JOURNAL ARTICLE AU - Ross J Simpson, Jr TI - Assessing the safety of drugs through observational research AID - 10.1136/hrt.2007.114785 DP - 2008 Feb 01 TA - Heart PG - 129--130 VI - 94 IP - 2 4099 - http://heart.bmj.com/content/94/2/129.short 4100 - http://heart.bmj.com/content/94/2/129.full SO - Heart2008 Feb 01; 94