Before the term "dyslexia" came to prominence, this learning disability used to be known as "word blindness." Common indicators of reading disability include difficulty with phonemic awareness—the ability to break up words into their component sounds, and difficulty with matching letter combinations to specific sounds (sound-symbol correspondence). Disorder of written expression (ICD-10 and DSM-IV-TR codes 315.2)
The DSM-IV-TR criteria for a disorder of written expression is writing skills (as measured by a standardized test or functional assessment) that fall substantially below those expected based on the individuals chronological age, measured intelligence, and age-appropriate education, (Criterion A). This difficulty must also cause significant impairment to academic achievement and tasks that require composition of written text (Criterion B), and if a sensory deficit is present, the difficulties with writing skills must exceed those typically associated with the sensory deficit, (Criterion C).Individuals with a diagnosis of a disorder of written expression typically have a combination of difficulties in their abilities with written expression as evidenced by grammatical and punctuation errors within sentences, poor paragraph organization, multiple spelling errors, and excessively poor penmanship. A disorder in spelling or handwriting without other difficulties of written expression do not generally qualify for this diagnosis. If poor handwriting is due to an impairment in the individuals motor coordination, a diagnosis of developmental coordination disorder should be considered. By a number of organizations, the term "dysgraphia" has been used as an overarching term for all disorders of written expression.
SLD are specific in the sense that these disorders each significantly affect a relatively narrow range of academic and performance outcomes. SLD may occur in combination with other disabling conditions, but they are not due primarily to other conditions, such as intellectual disability, behavioral disturbance, lack of opportunities to learn, or primary sensory deficits.The issue of defining learning disabilities has generated significant and ongoing controversy. The term "learning disability" does not exist in DSM-IV, but it has been added to the DSM-5. The DSM-5 does not limit learning disorders to a particular diagnosis such as reading, mathematics, or written expression. Instead, it is a single diagnosis criterion describing drawbacks in general academic skills and includes detailed specifiers for the areas of reading, mathematics, and written expression. United States and Canada
In the United States and Canada, the terms learning disability and learning disorder (LD) refer to a group of disorders that affect a broad range of academic and functional skills including the ability to speak, listen, read, write, spell, reason, organize information, and do math. People with learning disabilities generally have intelligence that is average or higher.