| The purpose of the study was to identify, from the single-subject research design literature, effective intervention methods for improving social and communication skills of children and youth with developmental disabilities. A second purpose was to examine the effects of different features of single-subject design studies such as zero-baselines and number of data points included in the studies, on the magnitude of effect-sizes. Using meta-analysis methodology, effect-sizes were calculated from a set of single-subject design studies published in peer reviewed journals from 1994 to 2005. The ITSACORR analysis, based on interrupted time series analysis, was used to compute effect sizes. The findings suggested effectiveness for different intervention methods to promote social and communication skills of children and youth with developmental disabilities, and provided information about the factors that affected the ES calculations. |
