医学统计 Chapter1-Descritive

Reference book
1. 方积乾. 医学统计学与电脑实验(第三版).上海 科学技术出版社 2006 2. 方积乾. 生物医学研究的统计方法. 北京: 高等 教育出版社 2007
Chapter 1 Descriptive Statistics
Vocabulary
Statistical description Statistical inference variable Frequency Distribution Frequency table Cumulative frequency Minimum maximum range Quartile Lower Quartile upper Quartile Inter- quartile range 统计描述 统计推断 变量 频率分布 频率表 累积频率 最小值 最大值 极差、全距 四分位数 下四分位数 上四分位数 四分位数间距
interval Count Symmetric Skew Positive skew negative skew Central position Variability Arithmetic Mean Geometric mean Median raw data Variance Standard Deviation feature
Medical Statistics
(full English class)
Ji-Qian Fang School of Public Health Sun Yat-Sen University
Introduction
to Medical Statistics
Vocabulary
statistics statistic medical statistics mathematical statistics homogeneity variation population sample randomization target population 统计学 统计量 医学统计学 数理统计学 齐性、同质 变异 总体 样本 随机化 目标总体

Medical Statistics: Application of mathematical statistics in the field of medicine

Why we need to study statistics? Three reasons: (1)Basic requirement of medical research. (2)Update your medical knowledge. (3) Management and treatment for your own data.
结构 表格 图形 数字指标 百分位数 变异系数 比 频率 强度 标准化 直接标准化 间接标准化 粗死亡率 标准化死亡比
Chapter 1 Descriptive Statistics
Statistics: Statistical description Statistical inference Statistical description: Describes the feature of the sample. Main forms: tables, plots and numerical indexes
Estimation of Probability----Frequency

n : number of observations (large enough) m : number of occurrences of random event A
: relative frequency or frequency of event A
About This course -- Teaching and Learning
Aim:
Training essential concepts and statistical thinking Learning some skills in design and analysis
Lectures
抽样误差 系统误差 测量误差 随机事件 频率 参数 设计 数据收集 分组 资料整理 资料分析
Statistics : The discipline concerned with the treatment of numerical data derived from groups of individuals (P. Armitage).
Random
By chance! Random event: the event may occur or may not occur in one experiment. Before an experiment, nobody is sure whether the event occurs or not.
区间 记数 对称 偏倚 正偏倚 负偏倚 中心位置 变异性 算术均数 几何均数 中位数 原始资料 方差 标准差 特征
structure table plot numerical index percentile Coefficient of variation ratio Relative frequency intensity standardization Direct standardization Indirect standardization crude death rate standard mortality ratio (SMR)
sampling error systematic error measurement error random event relative frequency parameter design data collection grouping data sortting data analysis
1.1 es and Data
1.1.1 Structure and feature of data
No. Age (years) Gender Treatment Systolic pressure (kPa) (1) 1 2 3 4 … 100 (2) 37 45 43 59 … 54 (3) Male Female Male Female … Female (4) Drug A Control Drug B Control … Drug B (5) 18.67 20.00 17.33 22.67 … 16.80 Diastolic pressure (kPa) (6) 11.47 12.53 10.93 14.67 … 11.73 (7) Normal Normal Normal Abnormal … Normal (8) Prominent Effect Effect No effect … Effect ECG Effectiveness
(1) Basic observed unit A patient is defined as an observed unit. (2) Recording item Group: treatment Response variables (反应变量) : systolic pressure, diastolic, pressure, ECG and effectiveness Covariates (伴随变量) : age and gender Variables: describe the properties of individuals. Different types of variables statistical methods

Statistic: A measure of certain property of a sample. It is often presented by Latin letters, such as s , p
The Basic Steps of Statistical Work
1. Design of study 2. Collection of data 3. Data Sorting 4. Data Analysis 5. Interpret the results
P(A) frequency
4. Parameter and statistic

Parameter : A measure of certain property of the population. It is often presented by Greek letters, such asμ, π ---- usually unknown

2. Population and sample

Population: The whole collection of individuals that one intends to study ---- Homogeneity but with Variation

Sample: A representative part of the population. Randomization: An important way to make the sample representative.

However, there must be some regulation in a large number of experiments.
3. Probability

Measure the possibility of occurrence of a random event. A : random event P(A) : Probability of the random event A P(A)=1 , if an event always occurs. P(A)=0, if an event never occurs.