THE LONG TERM EFFECTS OF EARLY INTENSIVE ABA INTERVENTION ON ADAPTIVE BEHAVIOR AND IQ IN ASD – A LONGITUDINAL STUDY ON EVIDENCE BASED TREATMENTS IN ITALY

Background: The studies about the effects of intervention in ASD show dramatic improvements thanks to intensive and early intervention but the question of how and why improvements come about is still controversial (Howlin, 1998). Despite the great deal of knowledge about early intervention programs in Autistic Spectrum Disorders, the most of the interventions for individuals with ASD in Italy are still based on anecdotic evidences or clinical judgments. Objectives: This study aims to evaluate the long term effects of an ABA early intensive (ABA-int), an ABA non intensive (ABA-non int) and an Eclectic intervention on the Vineland Adaptive Behavior Scale (VABS) scores and on the Leiter scores in ASD in Italy.
Methods: 34 participants with ASD (25M; 9F; aver.chron.age=6;7yrs;ds:33; aver.IQ=60). The participants were divided in three groups of intervention: ABA-int (10 hrs of DTT, 5 hrs of speech therapy a week); ABA-non int (5 hrs of DTT, 2 hrs of speech therapy a week); Eclectic. The participants were tested with the VABS and with the Leiter within a 6 months interval (T1-T2) and again after 24 months (T3). At the end of the study, all the participants got an ABA non-int or an eclectic intervention.

Results: After 6 mths: the VABS increased significantly in the ABA-int (1 yr; t=-3,41;df=8;p<0,05) and in the ABA-non int -10 mths (t= -8,61; df= 16; p<0,05). The IQ gained 23 scores in the ABA-int (t=-2,96; df=8; p<0,05) and 12 scores in the ABA non intensive group (t=-2,78;df=16;p<0,05). After 24 mths: the VABS score increased in the ABA-int (1;9 yr; t=-3,67;df=7;p<0,05) and in the ABA-non int (2;4 yrs; t=-5,4; df=14; p<0,05). The IQ scores increased of 21 scores only in the ABA-int (t=-2,6; df=7; p<0,05).
Conclusions: The results highlight a long term effects of ABA-int early intervention in ASD on adaptive skills and IQ.