Objective The impact of a screening programme on colorectal cancer (CRC) incidence in its target population depends on several variables, including coverage with invitations, participation rate, positivity rate of the screening test, compliance with an invitation to second-level assessment and endoscopists’ sensitivity. We propose a synthetic indicator that may account for all the variables influencing the potential impact of a screening programme on CRC incidence. Design We defined the ‘rate of advanced adenoma on the target population’ (AA-TAP) as the rate of patients who received a diagnosis of advanced adenoma within a screening programme, divided by the programme target population. We computed the AA-TAP for the CRC Italian screening programmes (biennial faecal immunochemical test, target population 50–69 year olds) using the data of the Italian National Survey from 2003 to 2016, overall and by region, and assessed the association between AA-TAP and CRC incidence fitting a linear regression between the trend of regional CRC incidence rates in 50–74 year old subjects and the cumulative AA-TAP. Results In 2016, the AA-TAP at a national level was 105×100 000, whereas significant differences were observed between the northern and central regions (respectively 126 and 149×100 000) and the South and Islands (36×100 000). The cumulative AA-TAP from 2004 to 2012 was significantly correlated with the difference between CRC incidence rates in 2013–2014 and those in 2003–2004 (p=0.009). Conclusion The AA-TAP summarises into a single indicator the potential impact of a screening programme in reducing CRC incidence rates.

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结直肠癌筛查项目对发病率影响的综合指标

目的 筛查计划对其目标人群中结直肠癌 (CRC) 发病率的影响取决于几个变量，包括邀请覆盖率、参与率、筛查测试的阳性率、对二级评估邀请的依从性和内窥镜医师的灵敏度。我们提出了一个综合指标，可以解释影响筛查计划对 CRC 发病率的潜在影响的所有变量。设计 我们将“目标人群的晚期腺瘤发生率”(AA-TAP) 定义为在筛查计划中被诊断为晚期腺瘤的患者比例除以计划目标人群。我们计算了 CRC 意大利筛查项目的 AA-TAP（两年一次的粪便免疫化学检测，目标人群 50-69 岁）使用 2003 年至 2016 年意大利全国调查的数据，总体和按地区评估 AA-TAP 与 CRC 发病率之间的关联，拟合区域 CRC 发病率趋势之间的线性回归50-74 岁的受试者和累积的 AA-TAP。结果 2016年全国AA-TAP为105×10万，而北部和中部地区（分别为126和149×10万）与南部和岛屿（36×10万）之间存在显着差异。2004 年至 2012 年累积的 AA-TAP 与 2013-2014 年和 2003-2004 年 CRC 发病率之间的差异显着相关（p=0.009）。结论 AA-TAP 将筛查计划在降低 CRC 发病率方面的潜在影响总结为一个单一指标。