Symptoms:

• Failure to produce and use sound appropriately
• Substituting one sound for another
• Omitting sounds

Signs and tests:

Certain medical conditions involve phonological disturbances. These should be ruled out before a diagnosis of phonological disorder is made. Such disorders include hearing impairment, anatomical problems (such as cleft palate), neurological conditions (such as cerebral palsy), and cognitive problems (like mental retardation).

The child should be evaluated for these and other similar conditions. Cultural considerations (such as bilingualism and the child's familial dialect) should also be considered to ensure correct diagnosis.