We investigated whether printed or videotaped information is more effective in enhancing colon cancer knowledge. Subjects (n = 1100) were randomized into three groups: to receive a booklet, view a videotape, or receive no intervention. Subjects receiving the intervention showed increased knowledge compared with control subjects (booklet = 23% and videotape = 26% vs no intervention = 3%). Findings suggest that personalized educational materials are effective in enhancing colon cancer knowledge.