Is it true dementia/mci is not based on cognitive screening alone? it requires an expert opinion from the clinician taking into account multiple data points?

You are quite correct. True dementia is beyond simple cognitive screening. This diagnosis requires more detailed mental testing, exclusion of depression, hearing& visual disabilities, occasional screening for environmental & language barriers,presence of toxicities,vitamin & thyroid deficiencies, side effects from medications, etc. Neuropsychiatric evaluators are key.

Agree with Dr. Colantino, as causes for reversible cognitive disorders need to be excluded prior to making a diagnosis of dementia, such as Alzheimer's.