NCSS PASS is one of the leading software tools for the design of medical trials and pharmaceutical or medical research in general. PASS provides the right methods for the power analysis of over 680 different statistical tests, confidence intervals and research scenarios.
Fast import of historical data – even in foreign data formats – and the simple interface help you focusing on the real problem: determining just the right sample size for your study.
Getting the right sample size involves just three steps:
 Choose the right study design from the navigator
 Enter the required parameters (typically: noise/standard deviation, relevant effect)
 Interpretation of results (Power, sample size)
That’s how easy NCSS PASS makes power calculation. All results will be visualized by highlevel scientific graphs. All graphs are highly customizable and will add an additional level of clarity to your reports.
NCSS PASS offers:
 Calculation of sample size and power
 Validated procedures
 Easy to learn, easy to use
 Professional graphics
 Helpful documentation as part of the output
 Easy export to all commonly used text editors
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PASS  Power Analysis & Sample Size Software
PASS has been finetuned for over 20 years, and has become the leading sample size software choice for clinical trial, pharmaceutical, and other medical research. It has also become a mainstay in all other fields where sample size calculation or evaluation is needed. PASS software performs power analysis and calculates sample sizes for over 680 statistical tests.
PASS Overview
PASS is a standalone system
Although it is integrated with NCSS, you do not have to own NCSS to run it. You can use it with any statistical software you want.
PASS is accurate
It has been extensively verified using books and reference articles. Proof of the accuracy of each procedure is included in the extensive documentation.
PASS comes with complete help system documentation
That contains tutorials, examples, annotated output, references, formulas, validation, and complete instructions on each procedure. All procedures are validated with published articles or books.
Choose PASS. It's more comprehensive, easiertouse, accurate, and less expensive than any other sample size program on the market.
Choosing A Procedure 
Enter The Values 
Further Information
 PASS and NCSS Homepage from the producer NCSS
 PASS complete documentation on the producers website
Trial version of the software PASS
The Producer (NCSS) provides a free trial version of the software. The trial version is 7day's long usable without any restrictions in it's features and/or functions. The license key for the trialversion can be upgraded to a full version, after purchasing an appropriate license. So there is no struggle with reinstallation or reregistrations of licenses.
You can access the trial version on the website of the producer, just click on the following link: http://www.ncss.com/download/pass/freetrial/
System Requirements for the Software PASS
Windows®  
Further Requirements 

Operating System  Windows XP, Vista, 7, 8, 10 (32/64Bit) Windows Server 2003, 2008, 2008 R2, 2012, 2012 R2 
Min. CPU  450 MHz or higher 
Min. RAM  256 MB 
Disc Space  120 MB 
Pass on MAC OS X
A Windows emulator (such as Parallels) is required to run PASS on a Mac!
New Features in PASS 14
PASS 14 adds over 25 new power and sample size procedures. Over 45 procedures were updated and/or improved.
New Procedures
Means
 Equivalence Tests for the Difference Between Two Paired Means
 NonInferiority Tests for Two Means in a ClusterRandomized Design
 Equivalence Tests for Two Means in a ClusterRandomized Design
 Superiority by a Margin Tests for Two Means in a ClusterRandomized Design
 Tests for the Difference of Two Means in a HigherOrder CrossOver Design
 Tests for the Ratio of Two Means in a HigherOrder CrossOver Design
 Tests for Fold Change of Two Means
 MxM CrossOver Designs
 MPeriod CrossOver Designs using Contrasts
 OneWay Repeated Measures
 OneWay Repeated Measures Contrasts
 OneWay Analysis of Variance Contrasts
 Confidence Intervals for OneWay Repeated Measures Contrasts
Rates and Counts
 Tests for the Difference Between Two Poisson Rates
 Tests for the Difference Between Two Poisson Rates in a ClusterRandomized Design
 Tests for the Ratio of Two Negative Binomial Rates
Survival
 Logrank Tests in a ClusterRandomized Design
 OneSample Logrank Tests
 OneSample Cure Model Tests
Regression
 Reference Intervals for Clinical and Lab Medicine
 Tests for the Difference Between Two Linear Regression Slopes
 Tests for the Difference Between Two Linear Regression Intercepts
 Mendelian Randomization with a Binary Outcome
 Mendelian Randomization with a Continuous Outcome
Acceptance Sampling
 Acceptance Sampling for Attributes
 Operating Characteristic Curves for Acceptance Sampling for Attributes
Verbesserte oder Veränderte Prozeduren in PASS 14
Means
 Tests for Two Means using Ratios
 Tests for Two Means in a ClusterRandomized Design
 NonInferiority Tests for the Difference of Two Means in a HigherOrder CrossOver Design
 NonInferiority Tests for the Ratio of Two Means in a HigherOrder CrossOver Design
 Equivalence Tests for the Difference of Two Means in a HigherOrder CrossOver Design
 Equivalence Tests for the Ratio of Two Means in a HigherOrder CrossOver Design
 Superiority by a Margin Tests for the Difference of Two Means in a HigherOrder CrossOver Design
 Superiority by a Margin Tests for the Ratio of Two Means in a HigherOrder CrossOver Design
 OneWay Analysis of Variance FTests
Rates and Counts
 Tests for One Poisson Rate
 Tests for the Ratio of Two Poisson Rates
Proportions
 Tests for One Proportion
 NonInferiority Tests for One Proportion
 Equivalence Tests for One Proportion
 Superiority by a Margin Tests for One Proportion
 Tests for Two Proportions
 Tests for Two Proportions in a Repeated Measures Design
 NonInferiority Tests for the Difference Between Two Proportions
 NonInferiority Tests for the Ratio of Two Proportions
 NonInferiority Tests for the Odds Ratio of Two Proportions
 Equivalence Tests for the Difference Between Two Proportions
 Equivalence Tests for the Ratio of Two Proportions
 Equivalence Tests for the Odds Ratio of Two Proportions
 Superiority by a Margin Tests for the Difference Between Two Proportions
 Superiority by a Margin Tests for the Ratio of Two Proportions
 Superiority by a Margin Tests for the Odds Ratio of Two Proportions
 Confidence Intervals for the Difference Between Two Proportions
 Confidence Intervals for the Ratio of Two Proportions
 Confidence Intervals for the Odds Ratio of Two Proportions
 Tests for Two Correlated Proportions (McNemar Test)
 NonInferiority Tests for the Difference Between Two Correlated Proportions
 NonInferiority Tests for the Ratio of Two Correlated Proportions
 Equivalence Tests for the Difference Between Two Correlated Proportions
 Equivalence Tests for the Ratio of Two Correlated Proportions
 Tests for Two Proportions in a ClusterRandomized Design
 NonInferiority Tests for the Difference of Two Proportions in a ClusterRandomized Design
 NonInferiority Tests for the Ratio of Two Proportions in a ClusterRandomized Design
 Equivalence Tests for the Difference of Two Proportions in a ClusterRandomized Design
 Equivalence Tests for the Ratio of Two Proportions in a ClusterRandomized Design
 Superiority by a Margin Tests for the Difference of Two Proportions in a ClusterRandomized Design
 Superiority by a Margin Tests for the Ratio of Two Proportions in a ClusterRandomized Design
 GroupSequential Tests for Two Proportions (Simulation)
 GroupSequential NonInferiority Tests for the Difference of Two Proportions (Simulation)
 GroupSequential NonInferiority Tests for the Ratio of Two Proportions (Simulation)
 GroupSequential NonInferiority Tests for the Odds Ratio of Two Proportions (Simulation)
 GroupSequential Superiority by a Margin Tests for the Difference of Two Proportions (Simulation)
 GroupSequential Superiority by a Margin Tests for the Ratio of Two Proportions (Simulation)
 GroupSequential Superiority by a Margin Tests for the Odds Ratio of Two Proportions (Simulation)