The Impact of Morphological Processing-Based Predicate Inflection Intervention on Spelling Accuracy in School-aged Children with Borderline Intellectual Functioning

Objectives: This study aimed to investigate the effectiveness of a morphological processing-based intervention on spelling accuracy in children with borderline intellectual functioning (BIF). Specifically, the intervention focused on facilitating the acquisition and application of predicate inflection rules to enhance spelling accuracy. Methods: Participants included three third-grade students with BIF who met specified selection criteria. A multipleprobe design across participants was employed, encompassing baseline and pre-tests (3 sessions), an intervention phase (12 sessions, including 4 sessions for generalization test), a follow-up test (1 session), and maintenance test (3 sessions). Dependent variables included spelling accuracy and error types. The intervention program was structured with visual aids and contextual examples to provide explicit instruction and guided practice in predicate inflection rules. Results: The morphological processing-based intervention produced significant improvements in spelling accuracy and reductions in spelling errors among the BIF students. Additionally, the intervention demonstrated generalization effects, with students successfully applying learned rules to untrained predicates. Enhanced spelling skills were also maintained in the follow-up phase, indicating the lasting impact of the intervention. Conclusion: This study highlights the potential of morphological processing-based interventions as an effective approach to improve spelling skills in children with BIF, as evidenced by observed performance gains. Further investigation is needed to assess the intervention’s long-term efficacy and applicability across diverse educational contexts and populations.