The California Evidence-Based Clearinghouse For Child Welfare rates the FAST model as a "3 - Promising Research Evidence" on its Scientific Rating Scale rating the published, peer-reviewed research available. For a list of studies, see https://www.cebc4cw.org/program/kids-families-and-schools-together-kids-fast/.
Results for the American Indian Adaptation were assessed in Kratochwill, T.R., McDonald, L., Levin, J.R., Young Bear-Tibbets, H., and Demaray, M.K. (2004). Families and Schools Together: an experimental analysis of a parent-mediated multi family group program for American Indian Children. Journal of School Psychology, 42, 359-383, as described on https://web.archive.org/web/20170705030737/https://www.childtrends.org/programs/families-and-schools-together-american-indian-adaptation/:
“In the evaluation immediately following FAST graduation, students whose offered the FAST program scored five points lower on teacher observed aggressive behaviors and four points lower on parent observed withdrawn behaviors than their matched comparisons. By the one-year follow up, FAST students were rated as less withdrawn by their teachers (6.6 points less than the control group) and more academically competent (5.6 points more than the control group). Though the FAST students did improve, some of the gap could be attributed to the worsening of scores for the control group. No differences were observed between the FAST students and the control group on measures of reading and math, though teachers did rate FAST students as being more academically competent than their control group counterparts. Moreover, general parent school participation improved across all schools. The authors of the study concluded that parents and children alike enjoyed the program given the 80% graduation rate and positive sentiments expressed at follow up.
“This study used a very small sample. However, given the study’s goal to create a cultural adaptation of a national intervention for a small, at-risk, ethnic population a larger population may have been difficult to obtain.”