EPH 751 Assignment 3 - Answers
(Due: 09/22/2015)
Exercise 1 (Lee, E. Statistical Methods for Survival Data Analysis, 1992, p. 103)
Table 1 Survival data of patients with cancer of the ovary diagnosed in
Connecticut from 1935 to 1944 (Cutler et al. 1960b).

Introduction to Survival analysis
1. Survival analysis
The objective of survival analysis is to describe aspects of the distribution of survival time from sample data
in order to make inferences about survival pattern in the population.
It is natural to t

A. Kaplan Meier (Product-Limit) estimate of the survival function
Data: Five patients with pancreatic cancer
ID
Survival time (months)
Vital Status
1
2
3
4
5
5
8
22
3
6
1
1
1
1
0
Vital status: 1 = dead 0 = censored
10B
1. Kaplan-Meier calculation of survi

EPH 751 Survival Analysis in Clinical Trials
Isildinha (Zizi) Reis
Fall 2015
Survival analysis
Describe events over time how many and when
Commonly reported sample estimates:
survival probability or survival rate (often expressed in %)
3-year overall sur

EPH 751 Assignment 6 (Cox analysis, question 13) : Answer
(13) Prepare a report. Provide plots and tables of main results and write some paragraphs that could be
included in a publication or presentation. Your text should describe the following:
a. Method

EPH 751 Assignment 7 (question 8-12) Answers
Multivariate analyses: Joint effect of various factors on disease-free survival
Adjust the RT+CAP versus RT comparison of dfs for cell type.
(8) Make a comparison between the two treatment groups controlling f

EPH 751 Assignment 4 - Answers
Excel dataset: cervical_30pts.xls. Survival (in days) for 30 patients with cervical cancer recruited to a
randomized trial of the addition of a radiosensitiser to radiotherapy (New therapy B, group=1) versus
radiotherapy alo

EPH 751 Assignment 5 - answers
Exercise 5.1 (survival rates)
Suppose a clinical trial to compare two treatments with respect to overall survival. The 3-year survival rates are
expected to be 35% for group 1 (control) and 50% for group 2 (new treatment). A

1
EPH 651 Assignment 1 Answers
The primary endpoint of a clinical trial is overall survival, defined as time from date of study
entry to death from any cause. Figure 1 shows sorted survival or follow-up times in months.
Event (death) times are represented

Kaplan-Meier (or Product-Limit): a nonparametric method for estimating survival probability
Table 1. Kaplan-Meier estimate of survival and cumulative incidence of death
for 24 patients with colorectal cancer *
Time Observed Number
(months) deaths
at risk