Speech and Language Prevalence

Speech and language impairments can present as a delay or a disorder, impairments can occur as a primary condition or with secondary conditions, such as, cognitive, autistic, learning, hearing, behavior and emotional impairments. A developmental delay or impairment may result in a speech and language disorder out of line with cognitive ability. Speech and Language Disorder is usually described in terms of ‘speech’ referring to phonetic or phonological impairments and ‘language’ referring to specific language impairments there is delay or disorder. Examples of this include stuttering, speech may be difficult to understand, nasal-sounding, unusual in pitch or and rhythm. Facial grimaces along unusual movements may accompany speech, such as groping to produce sounds, syllables, and words. Difficulty planning and sequencing movements for speech within the brain; speech may be unintelligible and not understandable. Receptive and expressive abilities may be impaired together such as in a disorder called developmental language delay in toddlers and preschoolers or language learning disability in school-aged children.
The prevalence of speech sound disorder in young children is 8 to 9 percent. By the first grade, roughly 5 percent of children have noticeable speech disorders; the majority of these speech disorders have no known cause. By the end of their first year most children have mastered the ability to say a few simple words. By the first grade, roughly 5 percent of children have noticeable speech disorders; 3 percent are male and two percent female. One category of speech disorder is fluency disorder, or stuttering, which is characterized by a disruption in the flow of speech. It includes repetitions of speech sounds, hesitations before and during speaking, and the prolonged emphasis of speech sounds. More than 15 million individuals in the world stutter 9 million males and 6 million females; most of whom began stuttering at a very early age. The majority of speech sound disorders in the preschool years occur in children who are developing normally in all other areas. Speech disorders also may occur in children who have developmental disabilities. Language impairments are diagnosed in people who have clinically significant impairments in their development of spoken language in the absence of sensory or neurodevelopment disorders which comes from birth with the continuation throughout their adulthood. Spoken language in this case includes the ability to understand words, sentences, and connected speech as well as the ability to express messages using appropriate vocabulary, grammar, and discourse. Variation in prevalence also appears to be affected by a pattern of recovery for many children during the early preschool years along with poor speech development. . Most studies reported a greater prevalence of the disability in males than females.
Between 6 and 8 million individuals in the United States have some form of language impairment. Disorders of language affect children and adults differently. For children who do not use language normally from birth, or who acquire an impairment during childhood, language may not be fully developed or acquired. Speech and language impairments affects individuals of all ages but occurs most frequently in young children between the ages of 2 and 6 who are developing language. Boys are 3 times more likely to stutter than girls. Most children, however, outgrow their impairment either by themselves or with speech & language programs.

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