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What is Intelligibility?

Intelligibility is the technical term for understandability of speech sounds and words. This is the term used in the field of speech science and speech therapy to quantitatively describe pronunciation accuracy. Whole word and speech sound intelligibility tell how easy it is for people to understand your pronunciation.

From Wikipedia:
Intelligibility is a measure of how comprehendible speech is, or the degree to which speech can be understood. Intelligibility is affected by spoken clarity, explicitness, lucidity, comprehensibility, perspicuity, and precision.

In fact, accuracy in pronunciation is the foundation skill for people to understand your spoken communication. Of course, listeners also use context, grammar, and vocabulary to help them understand the verbal information you give them.

What Intelligibility Scores Really Mean

Everybody wants people to grasp what they say, so a high intelligibility score is better than a low score. A large gain from taking an English speech course is better than a small gain. But exactly what practical real-life difference will a 30, 40, 50 or 100% increase in intelligibility make for a talker? For native born U.S. speakers talking English in a quiet place, average intelligibility score is 90%. In background noise like a classroom these speakers average 86%. These people rarely come to Clear Talk Mastery for help, unless they are trying to get rid of a strong regional US accent or dialect.

In comparison, average intelligibility for new students tested before they start our program has been 38% in quiet surroundings and 30% with background noise. (The range over 314 recent students has been 2% to 85%.) Listeners have had difficulty understanding what they say. This difficulty holds them back in their work and social life. People often just stop listening to a talker with a very low intelligibility score.

When native U.S. English speakers talk just above a whisper, they measure about 50% intelligibility. So a score around 50% for an international person means that listeners have to strain to understand them. It is about the same as listeners trying to get information from a native speaker talking a little louder than a whisper. In other words, listeners need to rely a lot on context, grammar and gestures to figure out what the international talker is saying.

For graduate students given a teaching assistant job, university departments like the students to aim for at least 70% intelligibility. That level sharply reduces complaints from those getting instruction.

International speakers themselves who reach at least 65% intelligibility say they have more confidence and comfort when speaking English. Those who reach 80% intelligibility often boast of glowing praise received from their employers and professional associates.

How Do We Help You to Increase Your Intelligibility?

The Clear Talk method is designed to increase your intelligibility. Our in-depth assessment of word and speech sound intelligibility, multiple syllable word intelligibility and other intelligibility skills allows us to accurately determine the precise elements you need to increase how understandable your English speech is to native-born Americans and other international people.

Our instruction is tailored for your exact needs. We use the assessment results to generate a customized textbook for you. We work with you through additional assessments and one-on-one tutoring via Skype, which provides video and audio internet communication. We give you specific directions for your home practice and practice in daily life. And we provide you with the tools of interactive video instruction and audio lessons for home practice.