FDA SAS Drug Formulation Stability Program

Division of Biometrics
Center for Drug Evaluation and Research
Food and Drug Administration
Date March 23, 1992

For further information contact Atiar Rahman: RAHMANAT@cder.fda.gov

The SAS/PC program system STAB is written to perform the expiration dating period estimation based on linear regression analysis. The statistical foundation of the program was documented in 1987 "GUIDELINE FOR SUBMITTING DOCUMENTATION FOR THE STABILITY OF HUMAN DRUGS AND BIOLOGICS."

SAS/PC version 6.03 is required to run the program. DOS version 3 or later version is assumed in these instructions, but not required.

[ Installation ] [Loading Software] [Using STAB Program]

To install:

Make sure that your config.sys file contains the lines

device=c:\dos\ansi.sys
files=50

Reboot the system if changes are made in your config.sys file. If you do not keep the DOS operating system in directory c:\dos, give the appropriate directory. Without ansi.sys, you cannot leave the SAS display manager by the "x" command. Without sufficient file handles, the stability program will not run.

To load the software:

Load the software (presumably from floppy drive A, to the current default drive and SAS directory) with the commands

mkdir \sas\stab
xcopy a:*.* \sas\stab

or equivalent procedure for loading.

As a precaution against accidental modification of the source files, you might want to enter

attrib +r \sas\stab\*.*

The STAB system contains a data file, six SAS macro files and an optional SAS/Graph file.

STAB.DAT is a SAS control file, to which the user adds current variable values, titles, and the DATA. STABNC.DAT is an alternate SAS control file with a few comments.

ANALYS1.SAS to ANALYS6.SAS are the SAS macro programs

STABGRAF.SAS is an optional program for SAS/GRAPH

README.BAT and HELPSTAB.BAT are optional files to display this document.

To use the STAB system:

1. Make a duplicate of the stab.dat file, to avoid changing the original, by the following or equivalent:

copy \sas\stab\stab.dat \sas\stab\stab1.dat

2. Start SAS (presumably using the Display Manager, with \SAS as the default directory.)

3. Load STAB1.DAT by entering the following on the command line

INCLUDE 'STAB\STAB1.DAT'

4. When STAB1.DAT is loaded, enter the data and other modifications, as per the instructions given in comments in

STAB1.DAT

5. After completing data and information entry, enter SUBMIT on the command line to run the STAB system.

6. Check the LOG listing for errors, and if none, save the output listing (LST) as detailed in the comments given in STAB.DAT.

7. If you want high resolution SAS graphs, enter CLEAR on the command line of the program window if a program is visible.

8. The STABGRAF.SAS file uses a permanent dataset created by STAB.DAT, so STAB.DAT needs to be run before STABGRAF.SAS.
Load STABGRAF.SAS by entering on the command line

INCLUDE 'STAB\STABGRAF.SAS'

9. Make any modifications needed (check graphics device type and the axis scales) and run by entering
SUBMIT on the command line.

The program may run through a series of graphs. After viewing the current graph, press the space bar once.

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