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Evidence from Direct Instruction
The same pattern is present in research on "Direct Instruction" (DI). Direct Instruction's approach to teaching reading is based on training children in phonemic awareness, followed by drills on phonics. DI maintains that students need to know how to sound out words before they can actually read with understanding.
On "decoding" tests (e.g. the WRAT, Wide Range Achievement Test), DI children do quite well, but their scores are clearly much lower on tests of reading comprehension (e.g. the MAT, Metropolitan Achievement Test, which also includes vocabulary).
This is true when DI children are tested in grade three (Becker et. al. 1981) and in grades four, five and six (summarized in Becker and Gersten, 1982, who note that while Direct Instruction children scored at national norms on decoding skills, they only scored between the 25th and 35th percentiles in reading comprehension).
Other follow-up studies show that when DI children are tested in the upper grades on standardized tests that include reading comprehension, the results are extremely modest (grades three, four and five; Meyer, Gersten and Gutkin 1984; grade nine (Meyer, 1984; Gersten, Darch and Gleason, 1988; Gersten, Keating, and Becker, 1988; summarized in Adams and Engelmann, 1996, p. 94). The average score in grade nine for DI students is only at about the 34th percentile.
The Clackmannanshire study
The Clackmannanshire study, done in Scotland, has been cited frequently as a victory for systematic phonics instruction. In first grade (primary 1), two different ways of teaching phonics were compared, and the lessons lasted for 16 weeks. A total of 177 children who received the winning approach, synthetic ("first and fast") phonics, were followed up to grade 7 (Johnson and Watson, 2005). The comparison group, the one that did not get synthetic phonics but had a different method of learning phonics, was not followed up.
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