DSM-IV-TR › Disorders usually first diagnosed in infancy, childhood, or adolescence › Communication disorders › Phonological disorder (formerly developmental articulation disorder) 

315.39 Phonological Disorder (formerly Developmental Articulation Disorder)

Diagnostic Features

The essential feature of Phonological Disorder is a failure to use developmentally expected speech sounds that are appropriate for the individual's age and dialect (Criterion A). This may involve errors in sound production, use, representation, or organization such as, but not limited to, substitutions of one sound for another (use of /t/ for target /k/ sound) or omissions of sounds (e.g., final consonants). The difficulties in speech sound production interfere with academic or occupational achievement or with social communication (Criterion B). If Mental Retardation, a speech-motor or sensory deficit, or environmental deprivation is present, the speech difficulties are in excess of those usually associated with these problems (Criterion C). If a speech-motor or sensory deficit or neurological condition is present, it should be coded on Axis III.

Phonological Disorder includes phonological production (i.e., articulation) errors that involve the failure to form speech sounds correctly and cognitively based forms of phonological problems that involve a deficit in linguistic categorization of speech sounds (e.g., a difficulty in sorting out which sounds in the language make a difference in meaning). Severity ranges from little or no effect on speech intelligibility to completely unintelligible speech. Sound omissions are typically viewed as more severe than are sound substitutions, which in turn are more severe than sound distortions. The most frequently misarticulated sounds are those acquired later in the developmental sequence (l, r, s, z, th, ch), but in younger or more severely affected individuals, consonants and vowels that develop earlier may also be affected. Lisping (i.e., misarticulation of sibilants) is particularly common. Phonological Disorder may also involve errors of selection and ordering of sounds within syllables and words (e.g., aks for ask).

Associated Features and Disorders

Although there may be an association with clear causal factors such as hearing impairment (e.g., due to chronic otitis media) or structural deficits of the oral peripheral speech mechanism (e.g., cleft palate), neurological conditions (e.g., cerebral palsy), cognitive limitations (e.g., Mental Retardation), or psychosocial problems, at least 3% of preschool children present with Phonological Disorders of unknown or suspect origin, which are often referred to as functional or developmental. There may be a delayed onset of speech. Some forms of Phonological Disorder, involving inconsistent errors, difficulty sequencing sounds in connected speech, and vowel distortions, are sometimes referred to as "developmental dyspraxia of speech."

Specific Culture and Gender Features

Assessments of the development of communication abilities must take into account the individual's cultural and language context, particularly for individuals growing up in bilingual environments. Phonological Disorder is more prevalent in males.

Prevalence

Approximately 2% of 6- and 7-year-olds present with moderate to severe Phonological Disorder, although the prevalence of milder forms of this disorder is higher. The prevalence falls to 0.5% by age 17 years.

Course

In severe Phonological Disorder, the child's speech may be relatively unintelligible even to family members. Less severe forms of the disorder may not be recognized until the child enters a preschool or school environment and has difficulty being understood by those outside the immediate family. The course of the disorder is variable depending on associated causes and severity. In children with mild to moderate phonological problems not due to a general medical condition, about three-fourths show spontaneous normalization by age 6.

Familial Pattern

A familial pattern has been demonstrated for some forms of Phonological Disorder.

Differential Diagnosis

Speech difficulties may be associated with Mental Retardation, a hearing impairment or other sensory deficit, a speech-motor deficit, or severe environmental deprivation. The presence of these problems may be established by intelligence testing, audiometric testing, neurological testing, and history. If the speech difficulties are in excess of those usually associated with these problems or if they interfere with the child's ability to be understood by significant others, a concurrent diagnosis of Phonological Disorder may be made. Problems limited to speech rhythm or voice are not included as part of Phonological Disorder and instead are diagnosed as Stuttering or Communication Disorder Not Otherwise Specified. Children with speech difficulties due to environmental deprivation may show rapid gains once the environmental problems are ameliorated.

Diagnostic criteria for 315.39 Phonological Disorder

1. Failure to use developmentally expected speech sounds that are appropriate for age and dialect (e.g., errors in sound production, use, representation, or organization such as, but not limited to, substitutions of one sound for another [use of /t/ for target /k/ sound] or omissions of sounds such as final consonants).
2. The difficulties in speech sound production interfere with academic or occupational achievement or with social communication.
3. If Mental Retardation, a speech-motor or sensory deficit, or environmental deprivation is present, the speech difficulties are in excess of those usually associated with these problems.

Coding note: If a speech-motor or sensory deficit or a neurological condition is present, code the condition on Axis III.

Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision^TM. Copyright 2000 American Psychiatric Association. All Rights Reserved.