Spoken language outcomes in limited language preschoolers with autism and global developmental delay: RCT of early intervention approaches
Lindsey Birdsall
Communication Disorders, Lehman College
SPE 755: Autism and Related Disorders
Professor Cheryl Goettche, CCC-SLP
August 4, 2023
This research article compares the impact of two treatment strategies, JASPER and DTT,
on the spoken language of autistic preschoolers who also have global delays and minimal language. This is an important subset of the autistic population to research because they have a
high-risk of developing into non-verbal communicators, and this prognosis poses unique challenges for both the autistic individual and the caregivers.
The two therapies researched take different approaches. JASPER is a play-based therapy
which targets social communication through Joint Attention, Symbolic Play, Engagement, and
Regulation. Implementing the strategy involves arranging the environment, balancing imitation
and modeling, incorporating play routines, and responding to children’s communication and language through expansion. DTT stands for Discrete Trial Therapy, and it is an ABA strategy
which emphasizes clinician modeling and explicit teaching, where correct behaviors are systematically reinforced through rewards. Targets include “imitation, play, matching, requesting, comprehension, learning readiness, and labeling” (Kasari et al., 2023). Previous research of both
JASPER and DTT has yielded positive results in different contexts, but neither has been researched in this particular population.
164 children, across 3 different cities, participated in this randomized controlled trial.
Children were carefully selected to make sure the samples compared were equivalent, and they
were also evaluated immediately before the study to establish baseline skills. Then, children re-
ceived one hour of therapy daily for six months at their preschool, and they were evaluated again
for progress. Six months after the conclusion of treatment, children were evaluated a third time
to test for generalization. Also worth noting is that between 4 and 6 months of treatment, caregivers were enrolled in an instructional program, one hour a week for eight weeks, which encouraged the adoption of treatment strategies at home (Kasari et al., 2023).
The impact of JASPER and DTT therapies on expressive language was the primary focus
of this study. Results were measured in three ways: 1. Reynell Developmental Language Scales,
2. Mullen Scales of Early Learning, and 3. a 10-minute natural language transcript, involving
both the child and primary caregiver, analyzed through SALT (Systematic Analysis of Language
Transcripts). Ultimately, the RCT revealed that, at the end of the initial six month period, both
therapies were impactful on expressive language, and there was no significant difference between the two. However, the results at 6 months were significantly different in smaller subset of
the sample tested. The children who, before treatment, were able to initiate joint attention made
more gains with JASPER than DTT. Also, importantly, the results differed significantly at the
six month follow-up, after parent-implementation. At that point, the families which had been implementing DTT experienced the most expressive language gains in their autistic preschoolers.
These are mixed results, so what conclusions can we draw which impact practice? SLPs,
who have tended to emphasize play-based therapies like JASPER, and ABA practitioners, who
take behavioral approaches like DTT, can both learn from each other and make thoughtful recommendations, customized for each child. The evidence suggests that, in the long term, globally
delayed and minimally verbal children who begin with baseline skills in joint attention gain the
most expressive language from JASPER, and those who do not gain the most from DTT. Also,
this study reveals parent-coaching is impactful in both therapies. In fact, parents who were
trained in DTT saw even more gains in their child’s expressive language in the 6 to 12 month period of implementation than they did in the original, 6 month clinician-led period.
References
Kasari, C., Shire, S., Shih, W., Landa, R., Levato, L., & Smith, T. (2023). Spoken language outcomes in limited language preschoolers with autism and global developmental delay: RCT of
early intervention approaches. Autism Research, 16, 1236–
1246. https://doi.org/10.1002/aur.2932