Introduction: Students with intellectual disability (ID) experience reading difficulties that can be a result of ineffective reading instruction. Although much research on reading instruction for students with ID has been done, most of this research has focused on sight words and isolated skills, and limited attention has been paid to other literacy skills such as reading comprehension, which is the ultimate goal in literacy. The main idea strategy is one of the reading comprehension strategies that has been found to be effective in improving students’ reading comprehension. It has been widely investigated among students with learning disabilities (LD), but little attention has been given to this strategy in improving reading comprehension for students with ID. This study aimed to address this gap in the literature.

Objective: This study examined the effectiveness of a main idea and self-monitoring strategy for improving reading comprehension of expository text of students with ID.

Method: Three students with ID who were in third, fourth, and fifth grade were selected to participate in the main idea strategy instruction. A multiple baseline, across participants, single-case design was utilized for 10 weeks, with four days of reading instruction sessions per week. After baselines had been established, the main idea and self-monitoring intervention phase was implemented for students as follows: student 1, 16 sessions; student 2, 10 sessions; student 3, 6 sessions. Students were taught for 30 minutes in each session how to generate the main idea from the passage by naming the subject and telling the important things about it. Sixty expository passages were randomly assigned to be used in baseline, intervention, and maintenance.

Results: Results revealed the effectiveness of the main idea and self-monitoring strategy in improving reading comprehension for students with ID. All three students' main idea identification mean score increased from the baseline to the intervention phase. Furthermore, during the maintenance phase, results showed all three participants continued to demonstrate an improvement in main idea identification over baseline performance. This suggested that the effects of the main idea intervention were sustained even after two weeks with no instruction.

Conclusions: Main idea intervention combined with a self-monitoring strategy was found to be effective in improving reading comprehension of expository passages for students with ID. The findings of this study are promising and provide evidence that students with ID can benefit from reading interventions that have been found to be effective for students with other disabilities (e.g. LD).