Instead of programming the interviews, the GEIS script contains all the information needed to describe the questionnaire and conduct the interview. A scripted system allows changes to be easily and quickly made to adapt to changing research needs. The GEIS script also provides a standard, non-proprietorial, open method of project documentation. This means that comparisons between survey projects can be achieved by publishing scripts.
The syntax is described in the file \GEIS\BIN\GEIS.TXT. If this file is missing it can be rebuilt using GEIS. From the script window, click on the editor button then click on the menu option File: Make syntax file. The syntax file is created in the CATI directory.