2006 Conference General Sessions



Barry Romich, P.E.
AAC Institute
1022 Heyl Road
Wooster, OH   44691-9786

Telephone: (330) 262-1984  x211
Fax: (330) 263-4829
Email: bromich@aacinstitute.org

Katya Hill, Ph.D., CCC-SLP
Communication Science and Disorders
School of Health and Rehabilitation Sciences
Forbes Tower
University of Pittsburgh
Pittsburgh, PA   16444-0001
Pittsburgh, PA    15260
Telephone: (412) 383-6564

Children and adults who rely on AAC (augmentative and alternative communication) receive services from speech-language pathologists (SLPs), occupational therapists (OTs), physical therapists (PTs), teachers, engineers, and other service providers.  These professionals are now expected to provide services in accordance with the principles of evidence-based practice (EBP). (ASHA 2001)  

Two types of evidence are used in EBP service delivery: external evidence and personal evidence.  External evidence is comprised of research reports, case studies, and even informal anecdotal evidence.  However, evidence can be conflicting and thus sometimes needs to be compared.  Judgments must be made regarding the reliability, validity, relevance, age, and other characteristics of evidence.  A free and easy to use source of evidence is the web site of the AAC Institute, a not-for-profit charitable organization dedicated to the most effective communication for people who use AAC.  At the site, evidence is divided into five levels and into categories according to single subject vs. group research.  The further distinction is made between studies in which subjects were actual users of AAC and those studies in which the subjects pretended to use AAC for the study.  External evidence helps establish the vision for the future that one needs to have when providing services.

The foundation of personal evidence goes beyond the identification of the values and expectations of an individual and includes a thorough appreciation of the personís abilities and needs.  The best foundational personal evidence includes the collection and analysis of language samples.  Many AAC systems today have language activity monitoring (LAM) (Hill & Romich 1999, 2001) as an internal feature.  LAM records the time and content of language events as they are generated.  However, language samples can be collected from any speech output AAC system using U-LAM (Universal Language Activity Monitor) PC software.  Further, U-LAM provides for recording keyboard notations as part of the time-ordered record.  U-LAM is available for both PC and PocketPC.

Analysis of LAM data can result in the AAC Performance Report, a set of seventeen quantitative summary measures of communication performance.  (Romich, et.al. 2003)  The AAC Performance Report can be easily generated using PeRT (Performance Report Tool) software.  The report appendices also include frequency and alphabetic order word lists from the language sample.

Comparison of external and personal evidence can be useful in determining the current status of communication performance for an individual.  Performance data provides the evidence for a critical appraisal of the outcomes achieved among the AAC systems used during a trial process.  Therapy time is precious for people who use AAC.  Comparison of external and personal evidence can identify those areas needing attention most and those not needing attention.  Therapy plans can then be developed accordingly.

Communication rate is important to people who use AAC.  One of the factors affecting communication rate is selection rate, the speed of making selections on the AAC system.  For most people, direct pointing is the fastest way to access an AAC system.  Selection rate is one of the summary measures of the AAC Performance Report.  By measuring selection rate for different selection techniques, the technique that produces the best results can be chosen objectively.

When the individual must access the system using a single switch it is important that the switch be the most effective possible.  This means choosing the right switch, placing or mounting it properly, and training in its use.  (King 1999)  

Single Switch Performance Test (SSPT) is a clinical tool to facilitate the measurement of performance using a single switch.  (Liffick 2005)  SSPT is software to allow a PC to be used to practice switch use and collect switch use data.  SSPT measures three parameters: 1) time to activate the switch, 2) time to release the switch, and 3) speed of repeated switch activation.  The opening screen allows the selection of background information and also the specific test to be administered.  Stimulus is provided by the computer and can be visual and/or auditory.  The switch is connected to the computer using a modified mouse with a jack in parallel with the mouse button switch.  This program is a free download from the AAC Institute web site.

Many people who use AAC also use their AAC systems for computer access.  Reasons include physical access issues and the availability of more powerful language representation methods.  In the past, computer and operating system manufacturers included a feature called Serial Keys to allow data entering the serial port to emulate the keyboard and mouse.  Macintosh OSX no longer offers this feature.  Serial Keys began to deteriorate in Windows98.  AAC Institute now offers AAC Keys for both platforms as a free download.  (Donations are appreciated and contribute to ongoing initiatives.)

These and other resources are available free, with a donation, or at low cost (<$100) from AAC Institute.  Use of these resources can result in optimized communication performance for people who use AAC.  This in turn can lead to the best life experience possible for this population.


American Speech-Language-Hearing Association (ASHA). (2001). Scope of Practice. Rockville, MD.

Hill, K., & Romich B. (1999). AAC language activity monitoring and analysis for clinical intervention and research outcomes. In Proceedings of the C-SUN Conference. Los Angeles, CA: CSUN.

Hill, K., & Romich, B. (2001).  A Language Activity Monitor to support AAC evidence-based practice.  Assistive Technology, 13, 12-22.

King, T. (1999).  Assistive technology: essential human factors.  Boston: Allyn and Bacon.

Liffick, B., Romich, B., Hill, K. (2005) ď A Single Switch Performance Evaluation Tool." Proceedings of HCI International 2005 Conference. Las Vegas, NV.

Romich, B., Hill, K., Seagull, A., Ahmad, N., Strecker, J., & Gotla, K (2003).  AAC performance report tool. In Proceedings of the RESNA 2001 Annual Conference [CD-ROM]. Atlanta, GA: RESNA Press.

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