Abstract
The main purpose of this research was to analyze the prevalence and diversity of reading comprehension difficulties in Spanish students of primary and secondary schools. We evaluated a large sample of students from the Canary Islands region that stretched from second grade of primary until the final year of secondary education. Once the percentage of students with reading comprehension difficulties was determined, we classified them in different categories: students with low intelligence, students with specific reading comprehension (poor comprehenders), students with deficit on reading words/pseudowords, absentee students and inmigrants. The results show that 20.2% of the student population present serious problems in understanding a text and 6.7% of the total is included in the category of poor comprehenders. Also we found a group of students with difficulties in decoding skills but whose performance on comprehension tasks was normal, showing that not all learning disability students have poor comprehension.