Power Analysis for Survival Analysis in PASS

PASS
Survival Analysis

Cox Regression
This procedure calculates the power and sample size for Cox’s proportional-hazards regression.

Log-Rank Survival Tests
The log-rank survival test compares two survival distributions. A simple procedure by Freedmen is very easy to specify because time values are not used. More advanced procedures by Lachin and Foullkes and Lakatos compare survival across the whole spectrum of time, not just at one or two points. These PASS modules allow the sample size and power of the log-rank test to be analyzed under very general conditions.

Group Sequential - Log-Rank
This procedure is used in clinical trials when interim statistical tests will be conducted before a trial is completed to determine if the trial should be stopped early. The alpha spending functions described by Lan and DeMets are implemented.

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New Procedures
Mixed Models
Logrank (Survival) Tests
Logrank Non-Inferiority Tests
Randomization Lists
Kappa Test for Agreement
CI - Means (6 Procedures)
CI - Proportions (2 Procedures)
CI - Regression Slope
CI - SD/Variance
(8 Procedures)
CI - Correlation
Microarray One-Sample/Paired
T-Tests
Microarray Two-Sample
T-Tests
Proportion Trend Tests
Normality Tests
TAD - Two Means
TAD - Two Proportions
Design of Experiments
(9 Procedures)

New Features
Simplified Interface
Improved Help System
Quick Launch
Macros (Programmability)

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PASS 2008
Released January 14, 2008

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Sample PASS Procedures & Reports

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Equivalence
Logrank (Survival) Tests
Means - 1 or 2 Groups (T-tests)
Means - Confidence Intervals
Means - Correlated or Paired
Means - Cross-Over Designs
Means - Many (ANOVA)
Mixed Models
Non-Inferiority
Probability Calculator
Proportion - 1 Group
Proportions - 2 Groups
Proportions - Confidence Intervals
Proportions - Correlated or Paired
Proportions - Many Groups
Randomization Lists
Regression/Correlation
ROC Curves
Special Calculators
Survival Analysis
Variances

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System Requirements
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