PT - JOURNAL ARTICLE ED - , TI - Amplifying the error AID - 10.1136/heart.87.5.422 DP - 2002 May 01 TA - Heart PG - 422--422 VI - 87 IP - 5 4099 - http://heart.bmj.com/content/87/5/422.short 4100 - http://heart.bmj.com/content/87/5/422.full SO - Heart2002 May 01; 87