Opinion ID: 1302539
Heading Depth: 4
Heading Rank: 1

Heading: Dr. Ruttenber's Testimony.

Text: The district court did not err in prohibiting Plaintiffs' epidemiologist expert, Dr. Ruttenber, from testifying that scientific extrapolation supports a finding that radiation below 40 rads could cause hypothyroidism or autoimmune thyroiditis. Plaintiffs assert that the district court's rulings impermissibly required epidemiological studies to be a prerequisite to causation testimony. See In re Hanford, 292 F.3d 1124; Kennedy v. Collagen Corp., 161 F.3d 1226, 1229-30 (9th Cir.1998). The court's ruling, however, did not go that far. The court only precluded Dr. Ruttenber from, first, speculating that such extrapolation would likely produce results showing causation below 40 rads, and, second, stating that current epidemiological data do not contradict or prevent such a finding. Because the data Dr. Ruttenber used to make these two conclusions were not reliable, see Daubert v. Merrell Dow Pharms., 509 U.S. 579, 589, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993), the district court did not abuse its discretion in excluding Dr. Ruttenber's opinion.