Features: Survival Analysis

Survival Analysis Options

Accrual
  • Prior to study
  • Constant rate for a given number of intervals
  • Varies from one interval to the next
Hazard rates
  • Constant for all study intervals
  • Varies from one interval to the next, proportional
  • Varies from one interval to the next, non-proportional
Attrition (non-compliance or drop-out)
  • None
  • Constant rate
  • Varies by time and/or by group
Statistical tests
  • Log Rank, Wilcoxin
Graphs
  • Export as WMF, EMF, BMP, copy to clipboard
Reports
  • Export as RTF, copy to clipboard
Tables
  • Export as data or as picture, copy to clipboard

Includes the procedures you need

In addition to survival analysis, includes modules to compute power for means, proportions, analysis of variance and covariance, multiple linear regression, logistic regression, equivalence tests, and more.


PDF Manual and Help system

The PDF manual (300 pages) explains the logic and proper application of power analysis. It also includes worked examples for each statistical procedure and details for all algorithms. An extensive Help system provides step-by step instructions for each procedure.


Tools and Features

INTERACTIVE GUIDE
This guide alerts you to the program’s features and offers suggestions for increasing power.
interactive guide screenshot
FIND THE SAMPLE SIZE AUTOMATICALLY
Click “Find N” and the program displays the sample size required for any level of power. You may specify an allocation ratio (e.g., 2:1) and you may specify that the accrual rate should vary from one time interval to the next.
finding sample size screenshot
ACCRUAL RATES
If the accrual rate varies simply specify the relative proportion of subjects to be entered during each interval (e.g. 1:1:2:2). When you click Find N the program computes and graphs the actual number to be entered during each interval.
accrual rates screenshot
researcher

"This is stunning in its clarity and efficiency."

Dr. Sal Mannuzza - New York University School of Medicine

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Power and Precision

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Power and Precision is a statistical power analysis software package for calculation of a sample size for a planned study. The program features an unusually clear interface, and many tools to assist the user in developing an understanding of power analysis.