Opinion ID: 774843
Heading Depth: 4
Heading Rank: 4

Heading: Expert Risk Assessment

Text: 49 Risk assessment is an accepted methodology practiced extensively throughout the medical, scientific, and regulatory communities over the past thirty years. See Bernard Goldstein & Mary Sue Henifen, Reference Guide on Toxicology in Federal Judicial Center Reference Manual on Scientific Evidence 193 (1994). Standard risk assessment involves four stages: hazard identification, dose-response assessment, exposure assessment, and risk characterization. Id. Metabolife argues that consistent with this methodology, its experts consulted a wealth of peer-reviewed articles, Food and Drug Administration adverse incident reports, 15 studies, laboratory reports, and other scientific materials to formulate their opinions. 50 The district court rejected the experts' risk assessments because they did not explain precisely how they use[d] the scientific literature to support their opinion[s]. Rather, the experts list[ed] numerous articles in scientific journals and simply state[d] that, after reviewing these articles [and other information], they [were] convinced that Metabolife 356 cannot cause serious health problems. 72 F. Supp. 2d at 1170. The district court was troubled by the titles of several articles cited, noting that it did not understand how articles such as these support the opinions of Metabolife's experts. . . . Id. 51 Metabolife contends that the district court's ruling was an abuse of discretion, arguing that since the articles referred to were in peer-reviewed journals, the experts were not required to explain specifically how each article impacted their opinion. In Metabolife's view, the explanation requirement only arises when there is an absence of peer-reviewed literature directly supporting the position held by the expert. 52 Neither the district court's nor Metabolife's application of the Daubert II requirements in entirely correct. Metabolife is correct that peer-review is highly probative under Daubert II, 43 F.3d at 1318-19, but here the articles were not written by the experts who now wish to interpret them. Metabolife's experts, through risk assessment methodology, are interpreting peer-reviewed articles written by other scientists. The district court, as gatekeeper, correctly noted that the methodology of their interpretation should be open to scrutiny. 53 However, the district court abused its discretion in its summary decision that the risk assessments were not adequately explained. 72 F. Supp. 2d at 1170. In Daubert II, we said that scientific evidence, such as a risk assessment, that is prepared for litigation and not peer-reviewed itself, may be bolstered through the testimony of . . . [the ] experts who prepared the evidence. 43 F.3d at 1319. For such a showing to be sufficient, the experts must explain precisely how they went about reaching their conclusions and point to some objective source . . . to show that they have followed the scientific method. . . . Id. 54 Here, Metabolife's experts explained the process of risk assessment and pointed to objective sources, but did not, in the district court's view, adequately explain how those objective sources related to their methodologies and eventual conclusions. We agree with the district court that the risk assessment evidence is complex, but complexity is not an adequate ground for exclusion. Examining the declarations of the scientists who prepared the risk assessments, it is clear that they have facially complied with Daubert II's verification requirement for evidence prepared in anticipation of litigation -the declarations explain the methodology of risk assessment and how the data found in peer-reviewed articles and adverse incident reports was used. See 43 F.3d at 1318-19. 55 However, due to the complexity of this evidence and our deferential role in reviewing the admissibility of scientific evidence, we are not prepared to override the district court's role as gatekeeper and hold that the risk assessment evidence is admissible. Rather, we simply hold that the wholly conclusory grounds for exclusion listed by the district court constitute an abuse of discretion. If on remand the district court wishes to plumb the depths of the precise relationship between the materials cited and the conclusions drawn, that is entirely within its province as a Daubert II gatekeeper.