Hi, welcoem to WP. I was diagnosed two years ago by a psychologist. The assessment involved a structured agree/disagree questionnaire (the AQ-test, which y ou can find online) as a screening tool (this test aloen cannot diangose or rule out AS), some unstructured discussions with me and my support workers (I received hoem support because I'd been given a semi-formal ASD diangosis by another agency already), a lengthey interview and set of questionnaires for my parents, and a DSM interview (when they walk you through the DSM criteria and ask you whether you think you meet them and why). The psychologist also had the reports from previous psych evals since childhood. The parent interview/questionnaires involved early development. If your parents are not alive anymore or are incapacitated or for another reason cannot be interviewed, you may be asked about early development yourself or someone else who remembers you as a child will be interviewed (eg. an older sibling). Other parets of testing may include IQ tests or personality tests, but I didn't get these cause I'd had them many times before. If you are assessed by a neuropsychologist, they may also do neuropsych evals (eg. attention, executive functioning, etc.), but I didn't get this type of evaluation.