[Progress in construction and verification of colorectal cancer risk prediction models: a systematic review].

Objective: To systematically review available risk prediction models evidence on construction and verification of colorectal cancer risk prediction models. Methods: "Colorectal neoplasms", "risk assessment", "colorectal cancer", "colorectal tumor", "colon cancer", "colon tumor", "rectal cancer", "rectal tumor", "anal cancer", "anal tumor", "risk prediction", "malignancy", "carcinogenesis", "model" were used as search keywords. Journal papers and grey literature were searched from Chinese electronic databases (CNKI and Wanfang) and English electronic databases (PubMed and Embase) from their inception to 30 Apr 2018. The language of literature was restricted to Chinese and English. The inclusion criteria were human-oriented researches with complete information for model construction,verification and evaluation. The exclusion criteria were informal publications such as conference abstracts, Chinese disertation papers, and non-primary research materials such as reviews,letters,and news reports. Descriptive characteristics,targeted population, study design, model construction method and prediction results were extracted. A total of 36 papers involving 27 models were included. The population characteristics of all included studies,the type of research, the method of model construction and the prediction results of the model were analyzed. Results: As for model construction,there were 13 European and American population based model studies,14 Asian population based model studies,including 7 Chinese mainland based model studies. According to the factors selected into the model, these models can be divided into traditional epidemiological models (17 models), clinical index combined models (4 models),and genetic susceptibility index combined models (6 models). As for model verification,only 9 models were cross-verified in the internal population after model construction, and the extrapolation of model prediction effect was not effectively evaluated; 17 models were verified in an external population; there was only one model verified in two external populations in terms of risk prediction effect; the area under the curve of 27 models was 0.56-0.85. Conclusion: The risk prediction model of colorectal cancer is in the development stage. The external evaluation of model prediction effect is less and the prediction ability is not good, and the existing models have limited exploration of clinical indicators.目的： 系统评价结直肠癌风险预测模型构建与验证情况。 方法： 以"结直肠癌""结直肠肿瘤""结肠癌""直肠癌""肛门癌""风险""危险""预测""预警""评估""评价""模型"和"colorectal neoplasms""risk assessment""colorectal cancer""colorectal tumor""colon cancer""colon tumor""rectal cancer""rectal tumor""anal cancer""anal tumor""risk prediction""malignancy""carcinogenesis""model"为关键词，系统检索中国知网、万方数据知识服务平台、PubMed和Embase数据库截至2018年4月发表的结直肠癌风险预测模型相关文献，语种限定为中文和英文。纳入标准为模型构建、验证及评价的信息完整；以人为研究对象。排除标准为会议摘要、中文学位论文等非正式发表文献；综述、述评、新闻报道等非一手研究资料。共纳入36篇文献，涉及27个模型。对纳入研究人群特征、研究类型、模型构建方法与模型预测结果等进行分析和比较。 结果： 13个模型基于欧美人群构建，14个基于亚洲人群构建，其中基于中国人群研究有7个；根据模型纳入因素分为传统流行病学因素模型（17个）、结合临床指标模型（4个）与遗传易感性指标模型（6个）。9个模型在构建后仅在内部人群中进行了交叉验证，模型预测效果的外推性未得到有效评价；17个模型在1个外部人群中得到验证；仅有1个模型的风险预测效果在2个外部人群中得到了验证；模型的曲线下面积为0.56~0.85。 结论： 结直肠癌风险预测模型研究处于发展阶段，模型预测效果的外部评价较少且预测能力不佳，且现有模型对于临床指标探索有限。.