1. Frequency Distribution
Example 9-1 There are 130 observations
on height of 14 years old female children (Table 9-1). Look at the raw data? vague and confuse! How to sort the data? ---- Frequency table !
There are two kinds of research:
Laboratory experiment and Clinical trial Medical survey
13.1 Principles of research design
1. 2. 3. 4. Control Balance Randomization Replication
(2) The use of frequency table Show the profile of data distribution. Symmetric? Skew ? Central position? Variability? Outliers? Frequency table is a good way to summarize the data ---- 130 figures are reduced to 22 figures and are much easier to present.
9.1 Statistical Description for Measurement Data
Vocabulary for Chapter 9-1
Frequency Distribution Frequency table Minimum maximum range Inter- quartile range Lower Quartile upper Quartilcy Count 频率分布 频率表 最小值 最大值 范围、极差 四分位数间距 下四分位数 上四分位数 区间 累积频率 记数
Table 9 -2 Height of 130 female children
Height 124 128 132 136 140 144 148 15215616 0-164 Total
Count
正正 正正正正 正正正正正正正 正正正正正 正正正 正
Freq. 2 3 11 22 39 27 16 5 3 2 130
安慰剂 互相对照 自身对照 标准对照 历史对照 均匀性 均匀的 前提条件 随意 重复 预试验 血沉 化学疗法 缓解率 对象选择 处理安排 数据搜集 效度 可重复
animal experiment community intervention trial intervene eligible subjects factor treatment factor non-treatment factors level objective accurate precise specific sensitive
(1) Steps a. Minimum, maximum and range. Range=162.6-125.9=36.7 b. Decide the interval of group. c. Build up the table. Count the observations, Frequency Cumulated frequency
Medical Statistics (full English class)
Ji-Qian Fang School of Public Health Sun Yat-Sen University
Chapter 9 Statistical Analysis For Measurement Data
动物实验 社区干预试验 干预 合格对象 因素 处理因素 非处理因素 水平 客观性 准确 精确 特异的 敏感的
The aim of research design: To get a reliable result in the lowest cost of manpower, time and money; To estimate the random error within the observed data; To promote the efficiency of the research
Chapter 13 Design of medical research
Chapter 13 Design of Medical Research (I)
design research design reliable random error efficiency laboratory experiment clinical trial medical survey control balance randomization replication treatment subject effect empty control 设计 研究设计 可靠 随机误差 效率 实验室实验 临床试验 医学调查 对照、对照组 均衡 随机化 重复 处理 对象 效应 空白对照
placebo mutual control self control standard control historical control homogeneity homogeneous prerequisite casual reproduce pilot study blood sedimentation chemotherapy remission rate subject selection treatment assignment data collection validity reproducible