The study compared an experimental group (n=26) who participated in weekly SIS sessions as an adjunct to existing treatment protocols for a period of 6-8 weeks, to a control group (n=14) who matriculated in treatment without the addition of SIS training for a period of 6-8 weeks. Subjects completed a battery of questionnaires at the beginning of the measurement period and at the end of the measurement period. The SASSI-2, The McMaster Family Assessment Device (FAD), and the Rotter Internal-External Locus of Control Scale were used to measure groups on recovery related variables at Pre-Test and Post-Test. Results demonstrated a consistent pattern of improvement over the time measure. The results of the interaction of group and time demonstrated a pattern of gains which did not reach statistical significance, partially as an artifact of the small sample size. An investigation of effect sizes was conducted to detect the effect of SIS training. The training was found to have a moderate effect size, which was consistent with other research using SIS training. Some areas for possible future research were addressed.

This study was designed to determine the effectiveness of intensive sibling group play therapy in: (a) improving the self-concept of child witnesses of domestic violence; (b) reducing internalizing behavior problems, such as withdrawal, somatic complaints, anxiety and depression, of child witnesses of domestic violence; (c) reducing externalizing behavior problems, such as aggression and delinquency, of child witnesses of domestic violence; and (d) reducing overall behavior problems of child witnesses of domestic violence. A second objective of this study was to compare the effectiveness of intensive sibling group play therapy and intensive individual play therapy on the above identified dimensions.