Intelligibility of Speech
Speech/language pathologists work with clients who have an inability to produce
speech sounds accurately.
Some of the factors taken into consideration when listening or evaluating
intelligible speech include:
- Does the child come close to correct production (distortion) or does he/she
completely omit the sound (i.e., hat – ha-).
- If he/she substitutes one sound for another (i.e., wed – red), is
it a typical substitution for this age or is it an unusual substitution that
confuses the listener?
- Do the errors render speech less intelligible (or more immature) than it
A general guideline for measuring intelligibility is as follows:
- 2-2-1/2 years – 50% intelligible to strangers, 80% intelligible to
- 3-1/2 years – 80 % intelligible to strangers, 95% intelligible to
- 4-1/2 years – 100% intelligible to strangers, 100% intelligible to
- Smooth blending of sound develops continuously through the ages of 4 – 7
The overall goal of speech therapy is to increase basic intelligibility. The
clinician may work on one age-appropriate sound or group of sounds at one time.
Treatment is individualized and determined upon initiation of therapy.