Objectives: The current study investigated the effect of early intensive Applied Behavioural Analysis intervention (ABA-int) in very young children with ASDs on standardized tests of cognitive performance (Leiter-R) and adaptive behavior (Vineland Adaptive Behavior Scale – VABS). We also analysed changes in severity of ASDs core symptoms as defined in the ADOS.
Methods: 27 children with ASDs (20M: 7F), age range 23 - 65 mths (mean age = 37 mths; SD = 12), received ABA-int (10 hrs of ABA in DTT form and 5 hrs of speech therapy at week), were compared with 16 children with ASDs, age range 23-73 mths (mean age = 43 mths; SD = 13) that received Eclectic interventions (play group, psicomotricity, music therapy, for an average of 4 hours - week). All the children were tested twice (T1-T2 = 12 months) with the Leiter-R scale, with the VABS and with the ADOS.
Results: The groups were equivalent at T1 for Leiter-R scale and VABS scores. After 6 months, there was a 23 point IQ gain in the ABA-int group (t = -3,85;df = 26; p<0,05) while the Eclectic group did not show any significant change in standardized test scores (t = -1,05; df = 15; p>0,05). VABS scores increased significantly both in the ABA-int (+ 7 mths; t = -3,31;df = 26; p<0,05) and in the Ecletic group (+ 6 mths; t = -3,86; df = 15; p<0,05). The children in the ABA-int group scored significantly lower on the ADOS (t = 5,34; df = 26; p<0,05) while the severity of ASDs symptoms in the Ecletic group remained stable.
Conclusions: Our results point to the effectiveness of early intensive behavioural intervention in very young children with ASDs for cognitive development and in reducing symptoms severity. At same time, as