The DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) contains the Diagnostic Criteria for most common mental disorders including. Below is the Diagnostic Criteria for diagnosing Learning Disorders

Learning Disorders (formerly Academic Skills Disorders)

315.00 Reading Disorder

Reading achievement, as measured by individually administered standardized tests or reading accuracy or comprehension, is substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate education.

The disturbance in Criterion A significantly interferes with academic achievement or activities of daily living that require reading skills.

If a sensory deficit is present, the reading difficulties are in excess of those usually associated with it.

315.1 Mathematics Disorder

Mathematical ability, as measured by individually administered standardized tests, is substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate education.

The disturbance in Criterion A significantly interferes with academic achievement or activities of daily living that require mathematical ability.

If a sensory deficit is present, the difficulties in mathematical ability are in excess of those usually associated with it.

315.2 Disorder of Written Expression

Writing skills, as measured by individually administered standardized tests (or functional assessments of writing skills) are substantially below those expected given the person’s chronological age, measured intelligence, and age-appropriate education.

The disturbance in Criterion A significantly interferes with academic achievement or activities of daily living that require the composition of written texts (e.g., writing grammatically correct sentences and organized paragraphs.)

If a sensory deficit is present, the difficulties in writing skills are in excess of those usually associated with it.

315.9 Learning Disorder Not Otherwise Specified

This category is for disorders in learning that do not meet criteria for any specific Learning Disorder. This category might include problems in all three areas (reading, mathematics, written expression) that together significantly interfere with academic achievement even though performance on tests measuring each individual skill is not substantially below that expected given the person’s chronological age, measured intelligence, and age-appropriate education.

Taken from: American Psychiatric Association: Diagnostic Criteria from DSM IV