Single Switch Performance Test(SSPT)

Many people with disabilities use single switches to control various items of assistive technology. Overall performance of an assistive technology system is determined by many factors, including how well the individual can activate the switch. The choice and positioning of switches is most effectively accomplished when performance is measured.

SSPT is software to facilitate measurement of the ability to activate a single switch. SSPT software measures the average time required to activate or release the switch (following visual and/or audio prompts) and also can measure the speed of repetitive activations.

SSPT is available in two forms. The Visual Basic program can run on a PC. The Java program can run on a Macintosh or on a PC that has the Java Runtime Environment. SSPT was developed by computer science students at Millersville University of Pennsylvania under the supervision of Blaise Liffick, Ph.D. and is distributed free of charge.

The switch under test is connected to the computer as a mouse button. This is generally done with a traditional computer mouse that has been modified by adding a switch jack (Instruction of making a modified mouse).

The SSPT program was written in Java in order to be able to be run on both Windows and Macintosh computers. However, this means that the computer must contain the Java Runtime Environment (JRE or J2RE). To check to see if JRE is in the computer, look in the program files. If JRE is not in the computer, it is available at without charge.

SSPT can be downloaded and is being distributed at no cost. However, your donation is an investment in the future of AAC services, resources, and the lives of individuals who use AAC. Please consider a donation to AACI. Your generosity will help grow our advocacy efforts, internet-based course offerings, podcasts and webinars, and continue to help people using AAC. All donations are tax-deductible.

Download the SSPT-VBsetup


Liffick, B., Romich, B., & Hill, K. (2005). A single-switch performance evaluation tool. In Proceedings of the 11th International Conference on Human-Computer Interaction. Las Vegas, NV.

Romich, B., Hill, K., & Liffick, B. (2005). Switch Performance Measurement Software. ). In Proceedings of the 2005 RESNA Conference. Atlanta, GA. [CD-ROM].

Romich, B., Hill, K., and Liffick, B. (2005). Free software for measuring single switch use performance. 20th Annual Conference on Technology and Persons with Disabilities. Los Angeles.

Free Single Switch Software: