Children with Autism Spectrum Disorders (ASDs) show significative improvements thanks to intensive and early ABA intervention (Howlin, 1998). Usually, the great deal of knowledge about the stability of the effect of prolonged ABA intervention consider the diagnostic reclassification and the academic achievements of children in regular education classrooms (Reichow,2009). No studies, for the best of our knowledge, monitored the stability of IQ scores and adaptive abilities after the end of ABA intervention. In particular, no study examined receptive and expressive language skills after the end of ABA intervention.
This study was designed to evaluate if the gain on Adaptive Skills and on IQ, obtained thanks to 4 yrs of ABA intervention, remain stable 1 yr after the end of ABA intervention and the start of an Eclectic intervention (play group, psicomotricity, music therapy).
35 participants with ASDs (26 M; 9 F; aver.chron.age=6;3 yrs; DS:2;6; aver.IQ=66; DS=25), divided at the beginning of the study in three groups of intervention: ABA-int (10 hrs of Discrete Trial Teaching [DTT] a week, 5 hrs of speech therapy a week); ABA-non int (5 hrs of DTT a week, 2 hrs of speech therapy a week); Eclectic intervention( an average of 4 hours a week). At the end of the 4th year, both ABA-int and ABA non-int intervention groups finished the ABA treatment and switched to Eclectic intervention. The participants were tested for the duration of this study (5 yrs) with the Vineland Adaptive Behavior Scale (VABS) and with the Leiter-R once a year.
The IQ scores remained stable at the end of the ABA intervention (F=7,413; df= 4; p <0,05) in the ABA-int goup (IQ scores: t1= 56; t2=92; t3=90; t4=87; t5=80) and in the ABA-non int group (IQ scores: t1= 49; t2=69; t3=55; t4=67; t5= 61) but not in the Eclectic group (IQ scores: t1= 76; t2=73; t3=70; t4=71; t5= 69). The VABS scores increased significantly in all the groups from t1 to t5 (F= 76,57; df=4; p<0,05). Only ABA-int and ABA non-int group improved in VABS Receptive Language (F=33,77; df=4; p<0,05) and in VABS Expressive Language (F=2,6; df=8; p<0.12).
The results highlight the stability of IQ scores in ABA groups after one year of interruption of ABA treatment. Moreover the data showed a significant improvement of Receptive and Expressive language in the ABA groups. This study shows evidences that ASD children maintain the gain obtained from ABA intervention when switching to an Eclectic intervention.