苏南地区大肠癌平均风险人群大肠进展期肿瘤发生风险评分系统的建立及验证

Establishment and validation of a scoring system for estimating advanced colorectal neoplasm risk in average-risk population in southern Jiangsu province

目的建立苏南地区大肠癌平均风险人群大肠进展期肿瘤发生风险评分系统，并评价其筛查效能。方法以接受结肠镜检查的苏南地区籍大肠癌平均风险人群为研究对象，通过问卷调查获取其人口学特征、既往疾病史、吸烟史、饮酒史、饮食习惯等信息。采用多元logistic回归分析方法建立大肠进展期肿瘤发生风险预测模型。根据模型中各变量的B值赋予分值，建立大肠进展期肿瘤发生风险评分系统，并进行内部人群验证。通过预测一致性、区分能力和筛查准确度评价评分系统的筛查效能。结果共纳入905例合格研究对象。所建立的评分系统由年龄、性别、冠心病、蛋类摄人、排便频率等5个变量组成，分值范围为0-10分，其预测的一致性好（P=0．205），区分能力良好（受试者工作特性曲线下面积为0．75，95％CI：0．69-0．82）。以2．5分作为筛查界值，其敏感度、特异度、准确率、阳性预测值、阴性预测值、阳性似然比、阴性似然比分别为93．8％、47．6％、50．1Vo、9．1％、99．3％、1．79和0．13。大肠进展期肿瘤在高风险人群（〉2分）中的比例（9．1％）显著高于低风险人群（0～2分）中的比例（0．7％，P〈0．001）。如果仅对高风险人群进行结肠镜筛查，则在减少45．4％结肠镜检查例数的情况下，可以筛查出93．8％的进展期肿瘤病例。结论所建立的大肠进展期肿瘤发生风险评分系统具有良好的筛查效能，可以作为大肠癌初筛工具，应用于苏南地区无症状平均风险人群的大肠癌筛查。

Objective To develop a scoring system for estimating advanced colorectal neoplasm risk in average-risk population in southern Jiangsu province, and to evaluate its screening efficiency. Methods An average-risk population of colorectal neoplasm in southern Jiangsu province, who underwent colonoscopy, was included in this study. All participants were asked to complete a questionnaire on demographic characteristics, medical history, smoking, alcohol consumption, dietary intake, and other factors that may be associated with advanced neoplasms. A multivariable logistic regression method was used to identify independent predictors of advanced neoplasms. A scoring system was developed from the logistic regression model by using a regression coefficient-based scoring method, and then was internally validated. The screening efficiency of the scoring system was assessed by its calibration, discrimination, and accuracy. Results A total of 905 average-risk participants were included in this study. The scoring system comprised 5 variables （age, sex, coronary artery disease, egg intake, and defecation frequency）, with scores ranging from 0 to 10. The system had good calibration （P=0. 205） and good discrimination （area under the receiver operating characteristic curve = 0.75, 95% confidence interval： 0. 69-0. 82）. If score 2.5 was used as the screening cut-off value, the sensitivity, specificity, accuracy rate, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were 93.8%, 47.6%, 50.1%, 9.1%, 99.3%, 1.79, and 0.13, respectively. Among the participants with low-risk （0-2） or high-risk （〉2） scores, the risks of advanced neoplasms were 0.7% and 9.1% （P〈0. 001）, respectively. If colonoscopy was used only for persons with high risk, 93.8% of persons with advanced neoplasms would be detected while the number of colonoscopies would be reduced by 45.4%. Conclusion The scoring system in this study hassatisfactory screening efficiency and can be used for preliminary screening of advanced colorectal neoplasms in average-risk population in southern Jiangsu Province.