Prevalence of colorectal cancer in symptomatic and asymptomatic patients undergoing total coloscopy A prospective, multi-center, case-control endoscopy study in a federal state in Germany

Interventions: Group 1: Symptomatic patients undergoing colonoscopy were investigated with respect to colon cancer and its precursor lesions
Group 2: Asymptomatic screening participants were matched with patients from arm1 with respect to age and gender.
Primary outcome(s): Prevalence of colorectal cancer and its precursor lesions in patients undergoing total colonoscopy in comparison to screening participants.
Study Design: Allocation: ; Masking: ; Control: ; Assignment: ; Study design purpose: screening

干预措施：
第1组：针对存在症状且接受结肠镜检查（colonoscopy）的患者，就结肠癌及其癌前病变开展相关调研；
第2组：将无症状筛查参与者按照年龄与性别与第1组患者进行匹配。
主要结局指标：对比接受全结肠镜检查（total colonoscopy）的患者与筛查参与者的结直肠癌(colorectal cancer)及其癌前病变的患病率。
研究设计：
分组方法：；
设盲：；
对照：；
分配方式：；
研究设计目的：筛查