Here is the relevant language from Best: “[A] doctor’s differential diagnosis is reliable and admissible where the doctor (1) objectively ascertains, to the extent possible, the nature of the patient’s injury…, (2) ‘rules in’ one or more causes of the injury using a valid methodology, and (3) engages in ‘standard diagnostic techniques by which doctors normally rule out alternative causes” to reach a conclusion as to which… [read post]