2003 Conference Proceedings

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Katya Hill
Edinboro University of Pennsylvania
AAC Institute

Barry Romich
Prentke Romich Company
University of Pittsburgh

Stephanie M. Cook
Edinboro University of Pennsylvania

According to the Amytrophic Lateral Sclerosis Association, an estimated 5,600 Americans are diagnosed annually with Amytrophic Lateral Sclerosis (ALS) or Lou Gehrig's Disease; approximately 15 new cases a day. There is an estimated 30,000 Americans that have ALS at any given point in time (ALSA, 2001). Many of these people will experience loss of all speech with deterioration of motor skills that preclude expressive communication using writing or typing over the course of the disease. In a retrospective study of 100 hospice patients with ALS, over 75% were not able to speak understandably during the terminal stage of their illness (Saunders et al., 1981). The field of AAC (augmentative and alternative communication) addresses this area of human need.

In addition to individuals with ALS who require AAC, other stakeholders include family members, friends, caregivers, teachers, employers, and other members of the community. Other professionals and stakeholders in the field of AAC who actively work to improve communication for these people include speech-language pathologists, occupational therapists, physical therapists, engineers, researchers, manufacturers, and agencies that provide funding for systems and services.

AAC and Individuals with ALS

For individuals with ALS who rely on AAC, while speech output assistive technology can provide some degree of mitigation, their communication performance is typically far lower than normal speech. And yet, there is a scarcity of information in the literature regarding how communication methods are employed to meet communicative needs.

The effectiveness of an AAC system is influenced by several variables. However, the main components of an AAC system that influence communication performance are: 1) the method of utterance generation, 2) the language representation methods available, 3) the access method, and 4) the voice output.

Methods of Utterance Generation: include spontaneous novel utterance generation (SNUG) and pre-stored messages.

Language Representation Methods: include single meaning pictures, alphabet-based methods, and semantic compaction.

Access Methods: include direct selection (keyboard or other pointing), scanning, and morse code.

Output Methods: include digitized and synthesized speech voice output.

The Importance of AAC Evidence-Based Practice

The American Speech-Language-Hearing Association (ASHA) (www.asha.org) Scope of Practice, the definition of the profession of speech-language pathology in the United States, was revised in early 2001 and now includes the expectations of data collection, outcomes measurement, and the provision of services in accordance with the principles of evidence-based practice (ASHA 2001). The AAC Institute (www.aacinstitute.org) has developed a model for evidence-based practice (figure 1) and offers evidence and services to support practice (Hill & Romich 2002). Automated AAC performance monitoring has contributed to a shift toward AAC evidence-based clinical practice that is being embraced widely. The recent development of methods, tools, and services to support AAC performance measurement has resulted in the clinical use of an AAC Performance Report of sixteen quantitative summary measures of communication performance (Hill & Romich, 2001). These data can be the foundation on which AAC system training results are measured and optimized. Quantitative data are an important component for appraising and evaluating the evidence used to make clinical decisions.

Asking the Right Questions for Evidence-Based Practice

Applying the principles of evidence-based practice requires formulating answerable questions based on information and data collected about the individual and external evidence. To be satisfactorily answered the question must be focused and well articulated. Well-formulated questions allow the most effective and efficient gathering and appraising of the evidence. The PICO model identifies four elements of a well-built clinical question (Newman & Harries, 2001). These elements are: 1) define the Patient or Problem, 2) define the Intervention, 3) give a Comparison, and 4) describe the Outcome. Two examples, applying the PICO might be:

  1. P = individual with ALS;
  2. I = AAC strategies using voice output communication aid (VOCA);
  3. C = use of various language representation methods;
  4. O = performance using various language representation methods.


  1. P = individual with ALS;
  2. I = AAC strategies using voice output communication aid (VOCA);
  3. C = use of various alternative access methods;
  4. O = measured selection and communication rates.

Before the evidence can be gathered and appraised, qualitative and quantitative performance data need to be collected to ensure that the evidence applies to the individual and the question.

Persons with ALS

For evidence-based practice to work successfully, persons with ALS need to be informed about and to exercise their right to have the most effective communication possible. The most effective communication goes far beyond offering a person with ALS a personal choice among several devices and systems. Rather, he or she needs to be informed about outcomes to be expected through the use of these strategies and devices. These outcomes need to be defined in relationship to performance differences that may exist for physical access, cognitive access for expert performance, language goals -- syntax, semantics, pragmatics, novel utterances, pre-stored utterances, core vocabulary, extended vocabulary, -- and possible strategies to achieve access and language goals. Intervention tactics need to be made clear to the person and his or her immediate personal milieu.

To achieve informed participation by persons with ALS and their support systems requires that the field of AAC develop a clearly defined and described set of possible outcomes and alternatives. Further, these outcomes and alternatives need to be portrayed in ways that are easy for people outside the field of AAC to understand. The development of such clear and comprehensible language is a tall order and needs to be a part of a general advance toward consumer input in evidence-based practice.

EBP requires active participation by persons with ALS and the family support system in all processes. As any consumer of health care services, persons with ALS need to be fully informed about the services being provided. As AAC consumers, they have the right to know the evidence being used to guide clinical decisions. Persons with ALS have the right to request and access case information and the qualitative and quantitative data being recorded that characterizes and measures performance. They also have a responsibility to ask questions about clinical experience, competencies, and the accountability of clinical services. Persons with ALS and family members not only have the responsibility to ask questions, but to learn the right questions to ask in order to understand and participate in clinical decisions, and finally how to evaluate the answers. All individuals have the right to a second opinion to compare the evidence.


AAC clinicians are ethically bound to hold the interests of the person with ALS paramount. Clinicians can use EBP to learn whether they are helping their clients achieve the most effective communication. As with consumers, clinicians must ask the right questions and find the right answers. Several steps can assist clinicians in learning the right questions.

If clinical competence means asking evidence-based questions, then, identifying the sources of evidence -- what kinds of data to use, what theoretical constructs to use in relationship to the data, becomes a first step. A second step is executing a search for the data. Once evidence has been gathered, the process of clinical appraisal is initiated. Clinical appraisal leads to implementing services and evaluating outcomes. EBP holds clinicians accountable for 1) acquiring necessary skills, 2) collecting and evaluating the evidence, and 3) implementing and measuring change.


The personal achievement of people who rely on augmentative and alternative communication depends on evidence-based practice being embraced by all parties. It is the only path to the most effective communication possible.


ALSA's Understanding ALS: Incidence of ALS. (December 2001). Retrieved July 25, 2002 from http://www.alsa.org/als/incidence.cfm

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

Hill, K.J. and Romich, B.A. (2001). A summary measure clinical report for characterizing AAC performance. In Proceedings of the RESNA Conference, Arlington, VA: RESNA Press. 55-57.

Hill, K., & Romich, B. (2002). AAC evidence-based clinical practice: A model for success. AAC Institute Press. Vol. 2 No. 1, 1-6.

Newman, Mark & Harries, David. (2001). Teaching/learning resources for evidence based medicine (EBP). Retrieved October 1, 2002 from:

Saunders, C., Walsh, T., & Smith, M. (1981). Hospice care in the motor neuron diseases. In C. Saunders & J. Teller (Eds.), Hospice: The living idea. London: Edward Arnold.

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