Expert Article Library

Family Doctor's "Differential Diagnosis" is Admissible Expert Testimony

Case Name: Westberry v. Gislaved Gummi AB (Click here for the full text of the case)

Court: United States Court of the Appeals for the 4th Circuit

Date: May 20, 1999

Expert: Medical Expert. Dr. W. David Isenhower, Jr., M.D., general practitioner

Issue: Whether Dr. Isenhower’s “differential diagnosis” (or “differential etiology”) method is admissible as expert testimony, even though he had not written any published peer-reviewed studies or conducted any lab testing on the subject.

Summary of case: Plaintiff worked in a factory where he came into contact with rubber gaskets manufactured by Defendant. Defendant applied a coating of talc to the gaskets prior to shipping. Defendant provided no warning that talc was dangerous and Plaintiff was in contact with high concentrations of airborne talc. Plaintiff alleged that Defendant’s negligent failure to provide warning aggravated his existed sinus condition forced him to undergo several surgeries. Dr. Isenhower was plaintiff’s personal physician.

Role of the expert: Dr. Isenhower testified that Plaintiff’s sinus condition was greatly worsened by talc exposure. He based his diagnosis on Plaintiff’s medical history before, during, and after his position change at the factory which brought Plaintiff into contact with the airborne talc. His technique is termed “differential diagnosis” by the medical community.

Challenges to the Expert's testimony: Defendant challenged Dr. Isenhower’s expert testimony on the grounds that he had not published any peer-reviewed articles or performed any independent research on talc effects or differential diagnosis. The court ruled that differential diagnosis was a technique that was commonly accepted in the scientific community and had been accepted in the court in a prior case. Defendant also challenged Dr. Isenhower’s failure to measure the amount of talc exposure, the admissibility of Dr. Isenhower’s diagnosis of the timing of the onset of the illness, and the fact that Dr. Isenhower did not provide reasoning as to why all other possible causes of the illness were discounted. The court ruled that the evidence supported a heavy exposure to airborne talc, and precise measurement was impracticable and unnecessary. It also ruled that the other two challenges were irrelevant. Dr. Isenhower’s expert testimony was held admissible.

Summary prepared by C. Wood, Student, University of California, Hastings College of the Law