PT - JOURNAL ARTICLE ED - , TI - Colorectal free papers 077–090 AID - 10.1136/gut.50.suppl_2.a21 DP - 2002 Apr 01 TA - Gut PG - a21--A25 VI - 50 IP - suppl 2 4099 - http://gut.bmj.com/content/50/suppl_2/a21.short 4100 - http://gut.bmj.com/content/50/suppl_2/a21.full SO - Gut2002 Apr 01; 50