“One of the most powerful intervention studies to date with older dyslexic students was conducted in Gainesville, Florida, through the Morris Child Development Center (Torgesen et al., 2001). Sixty students with severe reading disability in grades 3-5 who had been receiving special education services for an average of 16 months were provided 8 weeks of very intensive reading instruction. They were taught 1:1 by highly skilled teachers in two, 50-minute sessions, five days a week for 8 weeks, for a total of 67.5 hours of instruction. During this time, in the strongest instructional condition, their scores in phonemic decoding increased from below the 1st percentile to the 39th percentile, their scores in text reading accuracy increased from the 4th to the 25th percentile, and their scores in reading comprehension increased from the 13th to the 27th percentile.
After the study, about 40% of the students were “staffed out” of special education, while the rest remained with no further intervention from the study. At the two year follow-up point, the students scored at the 29th percentile in phonemic decoding, the 27th percentile in text reading accuracy, and the 36th percentile in reading comprehension. The reading comprehension of these students was slightly higher than would have been predicted from the level of their general verbal ability, which was at the 29th percentile.”
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