[Diagnosis of reading and spelling disorder].

The ICD-10 calls for the use of tables that account for the correlation between intelligence and spelling or reading, respectively (regression model) in the diagnosis of dyslexia. In this paper we discuss the consequences that arise from this recommendation with respect to the interpretation of psychometric tests. In addition, a table is presented that contains the data required to make diagnostic decisions based on the regression model. Furthermore, an expected prevalence rate was calculated using randomized computer data.