Abstract/Summary

Purpose We investigated the effectiveness of a highly individualized morphosyntactic intervention using the SHAPE CODINGTM system delivered at different dosages. Method Eight children with DLD aged 8;0-10;10 received ten hours of explicit individualized intervention for morphosyntax delivered in 30-minute individual sessions once per week for 20 weeks. Following at least four baseline probe tests, two grammatical targets per session received explicit instruction until they reached criterion (90%), when the next target was introduced. To control for session length and teaching episode density, either both targets received 20 teaching episodes per session, or one target received 10 teaching episodes and the other 30. Maintenance testing of completed targets was also carried out. Results Scores on probe tests post-intervention were significantly higher than during the baseline phase (d=1.6) with no change during the baseline or maintenance phases. However, progress during the intervention phase was highly significant. One participant showed significantly faster progress with intervention while one (with the lowest attention score) made little progress. When considering progress relative to cumulative intervention sessions, progress was faster with 30 teaching episodes per session and slower with 10. However, when cumulative teaching episodes was used as the predictor, all three within-session dosages showed very similar rates of progress, with the odds of a correct response increasing by 3.9% for each teaching episode. The targets that were achieved required an average of 40-60 teaching episodes. Conclusions With the exception of one participant, the individualized intervention was highly effective and efficient. Thus, the individualized target identification process and intervention method merit further research in a larger group of children. The cumulative number of teaching episodes per target provided across sessions appeared to be key. Thus, clinicians should aim for high teaching episode rates, particularly if the number of sessions is constrained. Otherwise, intervention scheduling can be flexible.