Classification of reading problems by the Q-technique of factor analysis.

The Q-technique of factor analysis was used to define subtypes of reading problems in terms of performance on 31 tests of rapid reading skills. Subjects included a group of 34 children with learning problems, language problems, and mental retardation. Three subgroups were identified within each group by the statistical classification procedure. For the reading group, one subgroup was characterized by slow oral word reading, a second by slow auditory-visual letter association, and a third by slow auditory-visual association of words and syllables. The first and second subgroups for the mixed group were essentially the same as the second and third subgroups for the reading group, and the third subgroup was characterized by slow visual matching. These results were compared with those of previous investigators, none of whom used multivariate correlational procedures for classifying reading disabilities. It was concluded that the use of statistical classification techniques would greatly facilitate the achievement of a consensus regarding the number and the types of developmental reading disabilities.