SAS is statistical analysis software that is used to analyse clinical trial data and generate a standard report that can be submitted to the regulatory authorities for approval of the study.
SAS has been established as a statistical analyses tool and for over 30 years has been used for various data analysis works worldwide. Like most software’s, SAS has also gone through a series of up gradations constantly and thus has many versions. Every new version introduces valuable changes in the software designing in order to improve the efficiency of the SAS programs as well as to add new features in the software. The purpose of a new release is usually to add new features, such as new options, procedures and functions to do different analyses.
Sometimes a release may be updated without adding any new features to it and this type of updating is called a technical support level or TS level up gradation. The technical support level upgrade mainly indicates bugs that users have encountered while running specific programs and that has been fixed in the next upgraded version.
During the earlier times, different upgraded versions of SAS were named according to their scheduled release years. The origin of SAS date back to the 1960s, but the first formal release came in 1972 and that version was called “version 72”. It ran only on IBM mainframe systems and included a core set of features that to this day are considered to be the most SAS like elements, including the data step and some of the most familiar procedures.
Many more procedures were added over the next future versions with advance features to perform complicated statistical analysis. For example, “Version 76” added the FORMAT procedure, allowing programmers to customize the way values appeared in the reports. SAS dates were also added to provide a standard way for time based data to be included in the statistical data for analysis. Further, “Version 79” was released that added support for a second operating system, CMS (content management system). It also added the DATASETS procedure, for managing SAS datasets and an early form of arrays. The Appending dataset procedure and a preliminary sort of macro language were among the features added in updated “version 82”.
Meanwhile, there was also an attempt to port SAS to other platforms, such as UNIX and VMS (vendor management system, which is a Web-based application that acts as a mechanism for business to manage and procure staffing services) since not everyone had access to an IBM mainframe system. After which version 4 was released.
Version 4: This was the first version for non IBM computers, to run on several mini computer manufactures, operating systems and hardwares. This version was mostly written in a subset of PL/I language. So it is called a portable SAS because of the portability of the code.
Version 5: This added many new SAS products and many programming features that programmers quickly came to depend on, such as macro language and array subscripts. This also introduced display manager, a full-screen environment in which users could interact with SAS.
Up to this point, SAS had been written in a combination of PL/I ((Programming Language One), FORTRAN (imperative programming language that is especially suited to numeric computation and scientific computing) and assembly language, but an effort was under taken to rewrite the entire program in C so that SAS could easily be ported to other operating systems. So the next version 6 was written in C language.
Version 6: This version was first released in 1986. This version was meant to run on an IBM PC which doesn’t have PL/I compiler to run. C language was the obvious choice for a portable rewrite of SAS. The early releases of SAS version 6 were very limited, because of the limited memory capacity of MS-DOS. Finally, the rewriting was complete, many new features were added and it even compiled on the IBM mainframe platform, although SAS had to acquire their own IBM mainframe C compiler in order to make this happen. The later releases of version 6 were thoroughly portable and were used throughout the 1990s on a wide variety of platforms, even on platforms as specialized as Mac, OS/2, Silicon Graphics and Primos.
Under the name of Multi Vendor Architecture, releases 6.06, 6.07 and 6.08 came with more than double the number of features in the SAS System and introduced a much more flexible design. For the first time, the SAS user interface was based on a windowing paradigm, rather than the older full-screen approach. Using the new SCL (Screen Control Language), programmers could develop window applications that would run in any environment. Engines were introduced so that SAS datasets could be stored in various different ways depending on the requirements. For the first time, SAS supported SQL. With SAS running on various platforms, products were added to connect one platform to another within a SAS session.
The later releases of versions 6.09 to 6.12 added more features to let SAS integrate more easily with other software’s. But in the mainframe environment, version 6 development stopped with release 6.09. To this version few more new features were added to release 6.09E for the mainframe environment.
Rebuilding SAS on more of an object-oriented framework gave programmers more room, especially in the sense of length. Variable names, which had previously been limited to 8 characters, could now be 32 characters long. Character values were no longer limited to 200 bytes; they could now be up to 32,767 bytes long. Another result was Output Delivery System, also known as ODS, which allowed SAS to generate web pages. These innovations first appeared in SAS 7 in 1998, after which some more extra features where included and SAS 7 gave way to SAS 8 in 1999. SAS 8 added more output options to ODS in each successive release, and this continued with SAS 9 in 2002.
SAS 9 added new text-handling features and significant support for XML. About half of SAS users skipped SAS 7 and 8 entirely and jumped directly from version 6 to 9. Inspite of these new progresses in terms of software up gradations, there was a dramatic decline in the number of platforms supported, which became essentially three: servers, PC’s and mainframes. However, the hottest new operating system, Linux, is now supported in two variations and has become the fastest-growing environment for SAS.
SAS has been established as a statistical analyses tool and for over 30 years has been used for various data analysis works worldwide. Like most software’s, SAS has also gone through a series of up gradations constantly and thus has many versions. Every new version introduces valuable changes in the software designing in order to improve the efficiency of the SAS programs as well as to add new features in the software. The purpose of a new release is usually to add new features, such as new options, procedures and functions to do different analyses.
Sometimes a release may be updated without adding any new features to it and this type of updating is called a technical support level or TS level up gradation. The technical support level upgrade mainly indicates bugs that users have encountered while running specific programs and that has been fixed in the next upgraded version.
During the earlier times, different upgraded versions of SAS were named according to their scheduled release years. The origin of SAS date back to the 1960s, but the first formal release came in 1972 and that version was called “version 72”. It ran only on IBM mainframe systems and included a core set of features that to this day are considered to be the most SAS like elements, including the data step and some of the most familiar procedures.
Many more procedures were added over the next future versions with advance features to perform complicated statistical analysis. For example, “Version 76” added the FORMAT procedure, allowing programmers to customize the way values appeared in the reports. SAS dates were also added to provide a standard way for time based data to be included in the statistical data for analysis. Further, “Version 79” was released that added support for a second operating system, CMS (content management system). It also added the DATASETS procedure, for managing SAS datasets and an early form of arrays. The Appending dataset procedure and a preliminary sort of macro language were among the features added in updated “version 82”.
Meanwhile, there was also an attempt to port SAS to other platforms, such as UNIX and VMS (vendor management system, which is a Web-based application that acts as a mechanism for business to manage and procure staffing services) since not everyone had access to an IBM mainframe system. After which version 4 was released.
Version 4: This was the first version for non IBM computers, to run on several mini computer manufactures, operating systems and hardwares. This version was mostly written in a subset of PL/I language. So it is called a portable SAS because of the portability of the code.
Version 5: This added many new SAS products and many programming features that programmers quickly came to depend on, such as macro language and array subscripts. This also introduced display manager, a full-screen environment in which users could interact with SAS.
Up to this point, SAS had been written in a combination of PL/I ((Programming Language One), FORTRAN (imperative programming language that is especially suited to numeric computation and scientific computing) and assembly language, but an effort was under taken to rewrite the entire program in C so that SAS could easily be ported to other operating systems. So the next version 6 was written in C language.
Version 6: This version was first released in 1986. This version was meant to run on an IBM PC which doesn’t have PL/I compiler to run. C language was the obvious choice for a portable rewrite of SAS. The early releases of SAS version 6 were very limited, because of the limited memory capacity of MS-DOS. Finally, the rewriting was complete, many new features were added and it even compiled on the IBM mainframe platform, although SAS had to acquire their own IBM mainframe C compiler in order to make this happen. The later releases of version 6 were thoroughly portable and were used throughout the 1990s on a wide variety of platforms, even on platforms as specialized as Mac, OS/2, Silicon Graphics and Primos.
Under the name of Multi Vendor Architecture, releases 6.06, 6.07 and 6.08 came with more than double the number of features in the SAS System and introduced a much more flexible design. For the first time, the SAS user interface was based on a windowing paradigm, rather than the older full-screen approach. Using the new SCL (Screen Control Language), programmers could develop window applications that would run in any environment. Engines were introduced so that SAS datasets could be stored in various different ways depending on the requirements. For the first time, SAS supported SQL. With SAS running on various platforms, products were added to connect one platform to another within a SAS session.
The later releases of versions 6.09 to 6.12 added more features to let SAS integrate more easily with other software’s. But in the mainframe environment, version 6 development stopped with release 6.09. To this version few more new features were added to release 6.09E for the mainframe environment.
Rebuilding SAS on more of an object-oriented framework gave programmers more room, especially in the sense of length. Variable names, which had previously been limited to 8 characters, could now be 32 characters long. Character values were no longer limited to 200 bytes; they could now be up to 32,767 bytes long. Another result was Output Delivery System, also known as ODS, which allowed SAS to generate web pages. These innovations first appeared in SAS 7 in 1998, after which some more extra features where included and SAS 7 gave way to SAS 8 in 1999. SAS 8 added more output options to ODS in each successive release, and this continued with SAS 9 in 2002.
SAS 9 added new text-handling features and significant support for XML. About half of SAS users skipped SAS 7 and 8 entirely and jumped directly from version 6 to 9. Inspite of these new progresses in terms of software up gradations, there was a dramatic decline in the number of platforms supported, which became essentially three: servers, PC’s and mainframes. However, the hottest new operating system, Linux, is now supported in two variations and has become the fastest-growing environment for SAS.
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