See website
http://www.ncjrs.org/html/ojjdp/jjbul2001_1_1/page5.html
"Substantiated report An investigation results in a “substantiated” report when the allegation of maltreatment is found to be valid and is supported by evidence under State law or policy. In different States, this disposition is also called “determined,” “founded,” or “true.” An unsubstantiated report is not the equivalent of a false or erroneous report. States vary as to the level of evidence needed to substantiate an allegation of maltreatment. It is likely that many valid reports of child maltreatment are categorized as unsubstantiated because the required level of evidence was not met."

This is what it sounds like to me. Good luck!!