实习3 病例对照研究【目的】通过课题资料分析, 掌握病例对照研究的基本原理，病例对照研究常用指标的计算及资料基本整理分析方法。
【时间】6～9学时。
【内容】第一部分病例对照研究的基本原理【课题一】1、BackgroundMany countries, especially industrialized countries, reported the annual mortality rate of lung cancer increased year by year since the 1920s. The mortality rate were 1.1/100,000 for male and 0.6/100,000 for female from 1901 to 1920, it increased to 10.6/100,000 for male and 2.5/100,000 for female from 1936-1939.It was raised that the smoking, air pollution and other risk factors were the cause of lung cancer, but it was also pointed out that the increasing lung cancer death rate is due to human longevity, aging of population and/or the improvement of diagnostic methods for lung cancer and so on, the latter resulted in the elevation of detection rate and the level of diagnosis for lung cancer.Question 1：To determine the relationship between lung cancer and smoking, what kind of epidemiological study should be performed? How to test the hyposis using the method? How to exclude other factors?2、Study methodAim at the above-mentioned problems, Doll and Hill studied the relationship between smoking and lung cancer using epidemiological methods. They collected inpatients of lung cancer from 20 hospitals in and around London (added some hospital in other cities later) as investigation subjects from April 1948 to February 1952, interviewers surveyed all the new patients of lung, stomach and colon cancer in those hospitals during those four years.Each survey case of lung cancer matched one case of other cancer who hospitalized over the same period as control. A concise questionnaire was developed to study the cause of the disease. Both case and control were surveyed the informations of past and present in detail, filled the uniform questionnaire with the exactly same items (Table 1). Surveys were carried out byinvestigators with four-year investigation experience and the investigation of control should be detailed and precise as same as case.Question 2：Why did they investigate the gastric and colorectal cancer patients of during the same period?Questions 3: Can the subjects represent the target population when they were sampled from inpatients of lung cancer? How to make it certain that control group was comparable to lung cancer group when we selected them among inpatients?表1 吸烟与肺癌关系调查表病例对照编号姓名________性别______出生年月__________ 年龄____岁，职业_______ 民族____ 家庭住址：__________________________________________ 何时迁来_____________年工作单位：_________________________________________地址______________________________________________________________________工种（职务）_________从事该工作年限_______年，工作中曾否接触过有毒有害物质：有，无；接触：①铀，②石棉尘，③放射性物质，④水泥，⑤锯末，⑥芥子气，⑦二氧化硫，⑧氯气_______________________________________________________在何时（年），多长时间__________________________________________________访问开始时间：_____点____分，结束时间：_____点____分，实际访问时间_______分。
对调查评论：_______________________________________________________________调查者签名：_______________________病史及诊断1．曾否患肺癌：有，无，确诊时间__________年__________月2. 曾否患其他癌症：有，无，患癌部位：___________ 确诊时间：_____年_____月3. 确诊单位：________________ 住院日期：________年_____月，病历号___________4. 确诊依据：①临床②X线③手术④病理5. 诊断：__________________________ 组织类型_____________________________ 1. 曾否吸过烟：曾，否；吸烟________年现在吸烟：吸，不吸2. 开始经常吸烟后，曾否吸过烟一个月以上，以后又吸：有，无____________________每次戒烟一个月以上总共戒烟多长时间？___________________________________第一次在___________年，有_______月，第四次在__________年，有_________月，第二次在___________年，有_______月，第五次在__________年，有________月,第三次在___________年，有_______月，总计________年。
3. 开始经常吸烟时年龄：______________岁。
4. 曾否吸烟达六个月以上：曾，否；吸烟量的变化：从___________年至____________年，平均每日吸烟________支，共_________年，从___________年至____________年，平均每日吸烟________支，共_________年，从___________年至____________年，平均每日吸烟________支，共_________年。
5. 经常吸：纸烟________________牌，烟叶。
6. 吸烟时是否吸入：吸入（深），不吸入（浅），吸入有____________年。
7. 吸非滤嘴烟：吸，不吸；吸________年。
吸滤嘴烟：吸，不吸；吸________年。
均吸，从___________年开始由吸___________烟改吸_____________烟。
8. 曾否吸过雪茄：吸，不吸；每周吸__________支，吸_____________年。
9. 曾否吸过烟斗烟：吸，不吸；每周吸___________次，吸___________年。
10.你爱人是否吸烟：吸，不吸；吸_________烟，每天平均吸______次。
吸_______年。
调查者__________调查日期_______年_____月_____日第二部分病例对照研究资料分析一、描述性统计【课题二】肺癌病人大多是经病理组织学/或痰的细胞学检查，少部分病人依据肺部X线检查或支气管镜检查确诊的。
事先规定75岁以上的病人不作为调查对象，并去除了误诊为肺癌最后订正诊断的病人80例，因故未能调查的肺癌病例408例（包括调查时已出院者189例，病危者116例，死亡者67例，耳聋者24例，不会英语者12例），被调查的肺癌病人大约占当时这些医院里肺癌病人总数的85%，共计1465例。
肺癌组和对照组配对的条件是：⑴年龄相差不超过5岁，性别相同；⑵居住地区相同；⑶家庭经济条件相似；⑷同期入院并住同一医院；（5）民族、职业、社会基层医治或者相似。
对照可以与肺癌病人同一个医院选择，并注意不将病因可能相同的疾病作为对照。
在资料分析之前或分组以后要测定对比病例组与对照组的均衡性，可分层测定，包括年龄、性别、职业、社会阶层、居住地区等，两组不应有显著性差异。