분야
hwp1.1 Study Designs
1.2 Survival Time
Chapter.2 Estimation of Functions and Parameters
2.1 Estimation of the Survival Function
2. 2 Some Survival Models
2.4 Estimating of the cumulative hazard
Ⅲ.Comparison of Survival Distributions
3.1 Non-parametric Method
3.2 Comparison of two exponential distribution.
Ⅳ. Correlation and Regression Analysis
4.1 Simple Regression and Correlation
4.2 Multiple Regression
․Retrospective Studies
․Prospective Studies
※ Survival Analysis
; Deals with analysis of data that have "time to an event".
※ Survival time
; Time until an event occurs.
※ Event
; a. relapse of a disease
b. death
c. response to a treatment
; Economical,
To obtain answers quickly because the cases are already available.
※Disadvantages of retrospective design
; Limitation in the accuracy of exposure history and uncertainly about the
appropriateness of the control sample.
2. Prospective Study
․Cohort Study
; One enrolls a group of persons and follows them over a certain period to observe the time at which a disease or another end point develops.
․Clinical trial
; A prospective study comparing the effect and value of intervention(s) against control in human subjects.
- prospective not retrospective
- intervention / equipment
therapeutic
drug
device
procedure
- control group
no intervention
placebo
current standard therapy
previous standard