The best way to improve intelligibility in adults involves working with the speaker, their listeners, and changing the communication environment

By Connie Porcaro
June 29, 2023

Improving speech intelligibility is one of the most common goals for clients working with speech-language pathologists (SLPs). Intelligibility involves a listener understanding a speaker’s message. Speech-language pathologists strive to apply evidence-based practice to ensure that the most effective treatment is selected for their clients. Current knowledge of research on which techniques/strategies have been demonstrated to be most effective will help both the SLP and client. The goal of Improving Speech Intelligibility in Adults: Clinical Application of Evidence-Based Strategies (Porcaro, 2023) is to provide students and professionals in the field of speech-language pathology with research-based evaluation and treatment methods. Such methods are critical to assisting adults communicate with their friends, families, and health care professionals. There are many medical challenges that can interfere with adults being understood, including impacts of strokes, accidents that affect the brain or nervous system, or diseases, like Parkinson’s, Multiple Sclerosis, or Amyotrophic Lateral Sclerosis (ALS or Lou Gehrig’s disease). Chapter 1 (Introduction to Intelligibility and Related Concepts) discusses various terms including comprehensibility and consideration of communication participation. A discussion of how function and disability is impacted by impaired intelligibility is provided for readers to consider the most functional types of treatment. Voice disorders, including laryngectomy, can also negatively impact intelligibility and this book is the first to describe this and what can be done to improve communication in these cases. Each chapter offers cases to illustrate how strategies would be utilized with actual patients.

A thorough evaluation of what is impacting the individual’s ability to speak clearly is a first step in improving their intelligibility. Chapter 2 (Impact of Speaker-related Factors on Intelligibility) provides SLPs with detailed information of how speech and voice disorders can reduce intelligibility. During evaluation of intelligibility, the SLP will typically record their patient reading or speaking and ask a listener to “judge” by writing down what they heard. Speech-language pathologists should be aware that the way they measure intelligibility can be affected by many factors, such as how they record the person’s voice, who is the judge of the speech, or even what words or sentences the person’s saying. Two chapters of the book describe formal tests (Chapter 3, Assessment of Speaker Structures and Functions) and measures available to assist with this process as well as more informal methods (Chapter 4, Factors Related to Meaningful Assessment of Intelligibility). Informal measures can be useful but should be conducted carefully to avoid incorrect information or overinflated scores. The book thoroughly describes research findings related to these areas and lays out plans for SLPs to obtain the most useful evaluation information to assist in forming treatment plans for their patients. If you are an SLP who does not measure intelligibility because you don’t have the right tests or think they’re too complicated, this book will help you find a functional, manageable way to record this important information about your client.

An initial solution for impaired intelligibility may be to consider what behaviors a speaker can change to be better understood. That’s a logical and simple place to start! The book contains two chapters related specifically to this topic. Chapter 5 (Speaker Subsystem Management Strategies to Improve Intelligibility) covers the “subsystems” of possible behavioral changes that can be implemented with clients to systems that create speech, including respiration, phonation, resonation, articulation, and prosody. This allows the SLP to consider individual challenges that might improve the client’s intelligibility, which is a more traditional approach. Chapter 6 (Speaker Management Strategies to Improve Intelligibility and Functional Communication) goes in depth into strategies proven to be effective that are more functional for clients. These include working together with the listener and how to best work as a team, considering how to supplement speech with gestures, and other user-friendly ideas. A helpful checklist for speaker strategies is included at the end of the chapter to ensure the SLP will not miss any great ideas!

Since we know many adult patients have permanent or progressive damage to their brain or nerves that impact communication, why put all the work on them? Addressing only speaker strategies does not allow the communication partner or listener to get involved and do their part. Chapter 7 (Listener Strategies to Improve Intelligibility and Functional Communication) uses research-proven information to assist SLPs in guiding communication partners to improve intelligibility. This chapter describes barriers listeners may experience and how to overcome them for more effective communication with family and friends. A checklist is provided to remind SLPs and listeners how to use strategies to maximize their understanding of clients with reduced intelligibility.

A final important consideration in the experience of sharing with another person is the communication environment. This can be a critical factor in understanding someone else. Think about the struggle when you lose cell phone coverage, or your zoom meeting freezes. Speakers and listeners can work together to ensure the environment supports successful communication. Chapter 8 (Strategies to Alter Communication Environment for Better Understanding) describes different types of noise, including those in the physical environment, like background noise, as well as psychological noise, not focusing on the conversation. A section on use of settings on phones and devices covers the best ways to enhance intelligibility when using technology.

Improving Speech Intelligibility in Adults: Clinical Application of Evidence-Based Strategies (Porcaro, 2023) provides students and professionals in speech-language pathology updated evidence that supports the most effective ways to improve communication skills in adult patients. Speakers can change their behaviors, but that may be challenging. Why not consider what listeners can do and how the communication environment can be altered? Speech-language pathologists who use the strategies in this book will feel confident in assisting patients and their families, friends, and health care professionals with improved communication.