The opinion of the court was delivered by: Wm. R.Wilson, Jr. United States District Judge
MDL Docket No. 4:03CV1507-WRW
Pending are several Daubert motions: Defendant's Motion to Exclude Expert Testimony of Drs. Klimberg and Waldron as to Specific Causation (Doc. No. 74); Defendant's Motion to Exclude Expert Testimony of Dr. Hollon (Doc. No. 79); Defendant's Motion to Exclude Testimony of Dr. Gueriguian (Doc. No. 82); Defendant's Motion to Exclude Expert Testimony of Dr. Sackett (Doc. No. 85); and Defendant's Motion to Exclude Expert Testimony of Dr. Austin (Doc. No. 91).*fn1 Also pending are Plaintiff'sMotion to Preclude Defendant's Experts from Testifying That There is No Reliable Scientific Evidence that Combination Hormone Therapy Can Cause Breast Cancer (Doc. No. 131)*fn2 and Defendant's Motion for Summary Judgment Re: Specific Causation (Doc. No. 59).*fn3 Oral argument was heard on July 13-14, 2006 and again on July 31, 2006.
The admission of expert testimony is governed by Rule 702 of the Federal Rules of Evidence, which reads:
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.*fn4
When a party proffers an expert witness, deciding whether Rule 702 is satisfied is a preliminary issue governed by Federal Rule of Evidence 104(a).*fn5 Rule 104(a) requires the proponent of evidence to establish its admissibility by a preponderance of the evidence.*fn6 In determining admissibility, the court is not bound by any of the rules of evidence, except with regard to privilege.*fn7
B. Legal Standard for Admissibility
The central inquiry under Rule 702 is whether the proffered expert's testimony is sufficiently reliable.*fn8 The trial court serves a gatekeeping function, ensuring that any expert testimony is reliable and relevant.*fn9
To be admissible, expert testimony must satisfy the two prongs of Rule 702.*fn10 First, it must be based on scientific, technical, or other specialized knowledge.*fn11 If the testimony is scientific, it must be grounded in the methods and procedures of science.*fn12 Likewise, "knowledge" requires more than a subjective belief or an unsupported speculation, requiring instead an appropriate level of validation.*fn13 Second, the testimony must be relevant, in that it must help the trier of fact either understand the evidence or determine a fact in issue.*fn14 The burden of establishing relevancy and reliability rests on the proponent of the expert testimony.*fn15
Courts have used a variety of factors to determine the reliability of proffered expert testimony. The most frequently discussed factors are those derived from the Supreme Court's opinion in Daubert, where the Court established that the trial court may consider:
(1) whether the theory or technique can be or has been tested; (2) whether the theory or technique has been subjected to peer review and publication; (3) whether the theory or technique has a known or potential error rate and standards controlling the technique's operation; and (4) whether the theory or technique is generally accepted in the scientific community.*fn16
Because the inquiry is "flexible and fact-specific, a court should use, adapt, or reject Daubert factors" as needed based on the facts of a particular case.*fn17
The most recent amendments to Rule 702 added three general standards for courts to use in determining the reliability and relevance of proffered expert testimony. First, the proffered testimony must be based on sufficient facts or data.*fn18 Second, it must be the product of reliable principles and methods.*fn19 Third, the expert must have applied those principles and methods reliably to the facts of the case.*fn20
The focus is not on the expert's conclusion, but on the methodology.*fn21 The proponent of the testimony "need not prove . . . that the expert's testimony is correct, but . . . must prove by a preponderance of the evidence that the testimony is reliable."*fn22 Determining the validity of an expert's conclusions is the duty of the finder of fact.
A. Defendant's Motion to Exclude Expert Testimony of Drs. Klimberg and Waldron as to Specific Causation (Doc. No. 74)
Drs. Suzanne Klimberg and James A. Waldron were retained by Plaintiff to testify on both the general and specific causation of Plaintiff's breast cancer.
Defendant asserts several reasons for excluding the expert testimony of Drs. Klimberg and Waldron: (1) the opinions were created exclusively for this litigation; (2) the opinions are not based on sufficient facts or data;*fn23 (3) differential diagnosis is not reliable to determine the cause of breast cancer; (4) and the "Gail Model" is not reliable to determine the cause of breast cancer.*fn24 Defendant also contends that Drs. Klimberg and Waldron are not qualified to testify because Dr. Klimberg has "never published -- or even presented -- the opinions regarding the cause of breast cancer" and Dr. Waldron's "previous experience with breast cancer was limited to analyzing breast biopsies and determining whether the tissue was cancerous, not identifying the cause of cancer."*fn25
Plaintiff counters that Drs. Klimberg's and Waldron's opinions are based on scientifically reliable evidence. Additionally, Plaintiff claims that as a surgical oncologist and director of the breast cancer program at the Arkansas Cancer Research Center at UAMS*fn26 (Dr. Klimberg) and a diagnostic surgical pathologist and professor of pathology at UAMS (Dr. Waldron), both experts are qualified to testify as experts regarding causation.
Defendant's attacks on Drs. Klimberg's and Waldron's qualifications do not pass muster. Both experts have experience and understanding regarding breast cancer and their opinions are bottomed upon scientifically reliable information.
In formulating their opinions, Drs. Klimberg and Waldron relied on their training, knowledge, and experience as a surgical oncologist and pathologist, respectively. They reviewed and relied on numerous published, peer-reviewed medical literature and studies. While both reports are primarily conclusive, rather than explanatory, I don't believe that either expert used improper methodology. Dr. Klimberg's report on general causation reads:
To make a causal assessment in an individual case, one would need to consider the totality of evidence, including statistical association, details about generally recognized and statistically significant risk factors, physiological response to the drugs, such as radiological evidence of changes in breast density before, during, and after hormone therapy use, pathological biomarkers in the breast tissue samples during biopsy and surgery, as well as duration of use of the hormone therapy drugs.*fn27
Defendant faults the experts for using differential analysis. However, reliance on differential analysis is not fatal when epidemiological studies also support the expert's conclusions.*fn28 Raising significant questions about the experts' ...