PASS 13 Update

Use the button(s) below to download the PASS 13 installation file. If PASS 13 is not yet installed on your computer, this will install the full version. If you already have PASS 13 installed, this will update your current installation to the newest version. Your personal files will not be affected.

PASS 13 Download

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File: PASS13Setup_v13_0_17.exe
Size: 88.7 MB
Current Version: 13.0.17
Released: November 2, 2018

Click here for minimum System Requirements


PDF documentation for PASS 13 is installed with the software and can be accessed through the Help System. The documentation is not available online at this time.

Update Release Notes

This page lists the changes that have been made to PASS 13 since it was released.

Version: 13.0.17

Released: November 2, 2018

1. Fixed power calculation error in the Tests for Two Correlated Proportions in a Matched Case-Control Design procedure. The author of the paper on which this procedure is based determined that the correction made in PASS 13 update 13.0.15 was unnecessary. The calculations in PASS have been updated to reflect the author’s corrections. This correction returns the PASS calculation results for the Tests for Two Correlated Proportions in a Matched Case-Control Design procedure to the same results obtained prior to PASS 15 update 13.0.15.

2. Fixed power calculation error in the Tests for Two Variances procedure. The power was not being calculated correctly in some cases when the group sample sizes are unequal.

Version: 13.0.16

Released: July 6, 2018

1. Corrected an error in the Multiple Contrasts (Simulation) procedure. When solving for Sample Size, the target power value was being set to 1-(User-Entered Value for Power). The correct input power value is now used.

2. Corrected an error that caused incorrect power and sample size calculations when entering “R1” in the Tests for Two Proportions in a Stratified Design (Cochran/Mantel-Haenszel Test) procedure when the computer’s system language setting was set to a South African language setting or any other language setting where R is a currency symbol.

3. Corrected a “Subscript out of Range” error in Hotelling’s One-Sample T2 procedure that occurred when the language setting on the machine uses a comma as the decimal.

4. This is the final PASS 13 Update.

Version: 13.0.15

Released: November 3, 2017

1. Fixed power calculation error in Tests for Two Correlated Proportions in a Matched Case-Control Design. The author of the paper on which this procedure is based discovered a calculation error in his software used to create the results in the paper. The calculations in PASS and the validation results have been updated to reflect the author’s corrections.

2. Corrected error in Normality Tests procedure. In some cases the power was being drastically underestimated for the Skewness test.

Version: 13.0.14

Released: February 14, 2017

1. Fixed an error in the Logrank Tests (Input Proportion Surviving) and Logrank Tests (Input Mortality) procedures. The procedures were not calculating the hazard rates correctly when using spreadsheet entry for the survival proportions or the mortality rates. PASS was calculating hazard rates for each row as though all previous survival proportions (or mortalities) were equal. The detail reports for these two procedures were also corrected to display appropriate values.

2. Fixed a problem in the Survival Parameter Conversion Tool. Mortality 1 Until T0 was not updating when changing Median Survival Time 1 or Hazard Ratio 1.

3. Corrected Tests for One ROC Curve procedure. If AUC0 = AUC1, the power should be undefined, but was being reported as 0.5.

4. Fixed Confidence Intervals for One Standard Deviation using Relative Error procedure. When solving for Relative Error, the search did not converge.

5. Fixed error in summary statements of 4 exponential survival procedures. Some statements were populated with incorrect information.

6. Corrected documentation and help messages relating to AUC0 and AUC1 in the Tests for One ROC Curve procedure.

7. Fixed Comparative Plot Labels in the Normality Tests (Simulation) procedure. Some labels were not appearing.

Version: 13.0.13

Released: September 22, 2015

1. Fixed two sample survival routines based on the Lakatos method to correct for errors that occurred when the group sample sizes were unequal. These errors amounted to power values that were off by no more that 2 or 3 percentage points when the sample size of one of the groups was up to twice that of the other. Equal group size power values were not affected.

Version: 13.0.12

Released: July 28, 2015

1. Fixed “Overflow” error in plots with extremely large axis values.

2. Fixed Anderson-Darling Normality Test and Range Normality Test calculation for large sample sizes. The power was incorrect for the Anderson-Darling Test when N > ~4000 (it was reported as 0.000 when it should have been 1.000 for very non-normal data). The Range Test is only available when N < 1000, but results were still appearing.

3. Fixed example templates for Confidence Intervals for One Proportion procedure. They were generating a "Type mismatch" error.

4. Fixed various minor documentation typos and omissions.

Version: 13.0.11

Released: May 7, 2015

1. General language issues fixed related to the reading of simulation distributions.

2. Fixed problem in 3-Variable 3D plots when displaying total N instead of N1 on the plot. The legend was still labeled as “N1” even though it contained values for “N”.

3. Fixed a problem with copying output containing text and images. When pasted in 3rd party software like Microsoft Word, only a reference to the image was assigned. When PASS was closed the images would disappear from the saved Word file.

Version: 13.0.10

Released: February 7, 2015

1. Fixed a problem that occurred when the computer language setting (e.g. Spanish, Colombia) uses a comma as both the decimal separator and the list separator. In this case, none of the procedures would run.

Version: 13.0.9

Released: February 4, 2015

1. Fixed an issue with the title of graphs when entering multiple values for the three multiple comparison (simulation) procedures.

2. Minor documentation corrections in Tests for Two Means (Simulation) procedure.

3. Minor documentation corrections in Two-Sample T-Tests Allowing Unequal Variance (Enter Difference) procedure.

Version: 13.0.8

Released: October 2, 2014

1. Fixes calculation problems with all Conditional Power procedures. We discovered that the book Chang (2008) on which all conditional power calculations are based has typos in the formulas for both conditional and predictive power on page 73. These typos were confirmed by the author, Mark Chang, himself. The correct formulas are given in Jennison and Turnbull (2000), pages 207-213. PASS has been updated so that the conditional and predictive power values are now calculated using the corrected formulas. The documentation was also updated with the correct formulas.

Version: 13.0.7

Released: August 28, 2014

1. Fixes slight documentation errors in the following procedures: Kendall's Tau-b Correlation Tests (Simulation), Spearman's Rank Correlation Tests (Simulation), Tests for One Mean (Simulation), Power Comparison of Tests of Variances (Simulation).

2. Fixes a problem in all procedures that include Futility Boundaries. Setting the Number of Skipped Futility Looks to something greater than 1 generated an overflow error.

3. In the Logrank Test (Input Mortality) procedure, the "Solve For" drop-down text was corrected and an issue with solving for Mortality Ratio with different (hidden) Treatment Group Parameters was fixed.

Version: 13.0.6

Released: May 13, 2014

1. Fixes a problem with several of the Survival Analysis procedures when using computer language settings other than English (i.e. that have a comma as the decimal separator). If the Group Allocation was set to Equal (N1 = N2), then this would generate a "Value of 0 is out of range" error.

Version: 13.0.5

Released: May 8, 2014

1. Fixes documentation errors in the Confidence Intervals for Michaelis-Menten Parameters procedure.

2. Fixes documentation errors in the Conditional Power of Logrank Tests procedure.

3. Fixes an error in several Tests for Two Proportions procedures (i.e. Inequality, Non-Inferiority, Superiority, Equivalence). Plots had wrong values on the Y-axis when solving for Odds Ratio, Ratio, or Difference.

Version: 13.0.4

Released: March 27, 2014

1. Fixes a problem with the search for sample size in Tests for One Proportion. In some instances when the proportions are very small, the calculated sample size was slightly overestimated.

2. Fixes some general documentation typos and omissions.

Version: 13.0.3

Released: March 4, 2014

1. Fixes a problem with the Mixed Models procedure for more complicated models. Some models were deemed non-estimable when they are, in fact, estimable.

Version: 13.0.2

Released: February 26, 2014

1. Help system index updated. Some links from within PASS were pointing to the wrong pages in the help system.

Version: 13.0.1

Released: February 19, 2014

1. Initial Release of PASS 13.

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