Adults with mild intellectual disabilities: can their reading comprehension ability be improved?

Adults with a mild intellectual disability (ID) often show poor decoding and reading comprehension skills. The goal of this study was to investigate the effects of teaching text comprehension strategies to these adults. Specific research goals were to determine (1) the effects of two instruction conditions, i.e. strategy instruction to individuals and strategy instruction in small groups in a reciprocal teaching context; (2) intervention programme effects on specific strategy tests (so-called direct effects), and possible differences between strategies; (3) (long-term) transfer effects of the programme on general reading comprehension ability; and (4) the regression of general text comprehension by the variables of technical reading, IQ, reading comprehension of sentences (RCS), and pretest and posttest scores on the strategies taught.

In total, 38 adults (age range 20-72 years; mean age of 36 years) with ID participated in the study. IQs ranged from 45 to 69 with a mean IQ of 58. The intervention programme involved 15 weekly lessons of 1 h each, taught during 3 months. Blocks of lessons included each of Brown and Palincsar's strategies of summarizing, questioning, clarifying and predicting, as participants read and studied narrative and expository texts.

Results indicated no significant difference between group and individual instruction conditions. Second, direct programme effects - as determined by posttest-pretest contrasts for strategy tests - were substantial, except for the questioning strategy. Third, even more substantial was the transfer effect to general text comprehension. Moreover, the results on this test were well maintained at a follow-up test. Finally, the variance of general reading comprehension ability was best explained by the test of RCS, and only moderately by the strategies trained.

The presently used intervention programme provides a good starting point for adults with ID to become better readers.