Support Intensity Scale (SIS) The Supports Intensity Scale - A (SIS-A) is a tool that is used to measure supports required for individuals, aged 16 years and older, with intellectual and developmental disabilities. The assessment is done during an interview with individuals and the people who know them well. Rhode Island uses the SIS-A to determine service needs and related levels of funding for individuals receiving developmental disabilities services. The SIS-A, which is supported by the American Association on Intellectual and Developmental Disabilities (AAIDD), includes questions to better assess the practical supports a person needs to live the most independent life possible. You can read Frequently Asked Questions about the SIS-A on the AAIDD site here. You can also read the SIS-A Fact Sheet here.