For your delectation and delight, desultory dicta on the law of delicts.

Samuel Tarry’s Protreptic for Litigation-Sponsored Publications

July 9th, 2017

Litigation-related research has been the punching bag of self-appointed public health advocates for some time. Remarkably, and perhaps not surprising to readers of this blog, many of the most strident critics have deep ties to the lawsuit industry, and have served the plaintiffs’ bar loyally and zealously for many years.1,2,3,4 And many of these critics have ignored or feigned ignorance of the litigation provenance of much research that they hold dear, such as Irving Selikoff’s asbestos research undertaken for the asbestos workers’ union and its legal advocates. These critics’ campaign is an exquisite study in hypocrisy.

For some time, I have argued that the standards for conflict-of-interest disclosures should be applied symmetrically and comprehensively to include positional conflicts, public health and environmental advocacy, as well as litigation consulting or testifying for any party. Conflicts should be disclosed, but they should not become a facile excuse or false justification for dismissing research, regardless of the party that sponsored it.5 Scientific studies should be interpreted scientifically – that is carefully, thoroughly, and rigorously – regardless whether they are conducted and published by industry-sponsored, union-sponsored, or Lord help us, even lawyer-sponsored scientists.

Several years ago, a defense lawyer, Samuel Tarry, published a case series of industry-sponsored research or analysis, which grew out of litigation, but made substantial contributions to the scientific understanding of claimed health risks. See Samuel L. Tarry, Jr., “Can Litigation-Generated Science Promote Public Health?” 33 Am. J. Trial Advocacy 315 (2009). Tarry’s paper is a helpful corrective to the biased (and often conflicted) criticisms of industry-sponsored research and analysis by the lawsuit industry and its scientific allies and consultants. It an ocean of uninformative papers about “Daubert,” Tarry’s paper stands out and should be required reading for all lawyers who practice in the area of “health effects litigation.”

Tarry presented a brief summary of the litigation context for three publications that deserve to remembered and used as exemplars of important, sound, scientific publications that helped changed the course of litigations, as well as the scientific community’s appreciation of prior misleading contentions and publications. His three case studies grew out of the silicone-gel breast implant litigation, the latex allergy litigation, and the never-ending asbestos litigation.

1. Silicone

There are some glib characterizations of the silicone gel breast implant litigation as having had no evidentiary basis. A more careful assessment would allow that there was some evidence, much of it fraudulent and irrelevant. See, e.g., Hon. Jack B. Weinstein, “Preliminary Reflections on Administration of Complex Litigation” 2009 Cardozo L. Rev. de novo 1, 14 (2009) (describing plaintiffs’ expert witnesses in the silicone gel breast implant litigation as “charlatans” and the litigation as largely based upon fraud). The lawsuit industry worked primarily through so-called support groups, which in turn funded friendly, advocate physicians, who in turn testified for plaintiffs and their lawyers in personal injury cases.

When the defendants, such as Dow Corning, reacted by sponsoring serious epidemiologic analyses of the issue whether exposure to silicone gel was associated with specific autoimmune or connective tissue diseases, the plaintiffs’ bar mounted a conflict-of-interest witch hunt over industry funding.6 Ultimately, the source of funding became obviously irrelevant; the concordance between industry-funded and all high quality research on the litigation claims was undeniable. Obvious that is to court-appointed expert witnesses7, and to a blue-ribbon panel of experts in the Institute of Medicine8.

2. Latex Hypersensitivity

Tarry’s second example comes from the latex hypersensitivity litigation. Whatever evidentiary basis may have existed for isolated cases of latex allergy, the plaintiffs’ bar had taken and expanded into a full-scale mass tort. A defense expert witness, Dr. David Garabrant, a physician and an epidemiologist, published a meta-analysis and systematic review of the extant scientific evidence. David H. Garabrant & Sarah Schweitzer, “Epidemiology of latex sensitization and allergies in health care workers,” 110 J. Allergy & Clin. Immunol. S82 (2002). Garabrant’s formal, systematic review documented his litigation opinions that the risk of latex hypersensitivity was much lower than claimed and not the widespread hazard asserted by plaintiffs and their retained expert witnesses. Although Garabrant’s review did not totally end the litigation and public health debate about latex, it went a long way toward ending both.

3. Fraudulent Asbestos-Induced Radiography

I still recall, sitting at my desk, my secretary coming into my office to tell me excitedly that a recent crop of silicosis claimants had had previous asbestosis claims. When I asked how she knew, she showed me the computer print out for closed files for another client. Some of the names were so distinctive that the probability that there were two men with the same name was minuscule. When we obtained the closed files from storage, sure enough, the social security numbers matched, as did all other pertinent data, except that what had been called asbestosis previously was now called silicosis.

My secretary’s astute observation was mirrored in the judicial proceedings of Judge Janis Graham Jack, who presided over MDL 1553. Judge Jack, however, discovered something even more egregious: in some cases, a single physician interpreted a single chest radiograph as showing either asbestosis or silicosis, but not both. The two, alternative diagnoses were recorded in two, separate reports, for two different litigation cases against different defendants. This fraudulent practice, as well as others, are documented in Judge Jack’s extraordinary, thorough opinion. See In re Silica Prods. Liab. Litig., 398 F. Supp. 2d 563 (S.D. Tex. 2005)9.

The revelations of fraud in Judge Jack’s opinion were not entirely surprising. As everyone involved in asbestos litigation has always known, there is a disturbing degree of subjectivity in the interpretation of chest radiographs for pneumoconiosis. The federal government has long been aware of this problem, and through the Centers for Disease Control and the National Institute of Occupational Safety and Health, has tried to subdue extreme subjectivity by creating a pneumoconiosis classification schemed for chest radiographs known as the “B-reader” system. Unfortunately, B-reader certification meant only that physicians could achieve inter-observer and intra-observer reproducibility of interpretations on the examination, but they were free to peddle extreme interpretations for litigation. Indeed, the B-reader certification system exacerbated the problem by creating a credential that was marketed to advance the credibility of some of the most biased, over-reading physicians in asbestos, silica, and coal pneumoconiosis litigation.

Tarry’s third example is a study conducted under the leadership of the late Joseph Gitlin, at Johns Hopkins Medical School. With funding from defendants and insurers, Dr. Joseph Gitlin conducted a concordance study of films that had been read by predatory radiologists and physicians as showing pneumoconiosis. The readers in his study found a very low level of positive films (less than 5%), despite their having been interpreted as showing pneumoconiosis by the litigation physicians. See Joseph N. Gitlin, Leroy L. Cook, Otha W. Linton, and Elizabeth Garrett-Mayer, “Comparison of ‘B’ Readers’ Interpretations of Chest Radiographs for Asbestos Related Changes,” 11 Acad. Radiol. 843 (2004); Marjorie Centofanti, “With thousands of asbestos workers demanding compensation for lung disease, a radiology researcher here finds that most cases lack merit,” Hopkins Medicine (2006). As with the Sokol hoax, the practitioners of post-modern medicine cried “foul,” and decried industry sponsorship, but the disparity between courtroom and hospital medicine was sufficient proof for most disinterested observers that there was a need to fix the litigation process.

Meretricious Mensuration10 – Manganese Litigation Example

Tarry’s examples are important reminders that corporate sponsorship, whether from the plaintiffs’ lawsuit industry or from manufacturing industry, does not necessarily render research tainted or unreliable. Although lawyers often confront exaggerated or false claims, and witness important, helpful correctives in the form of litigation-sponsored studies, the demands of legal practice and “the next case” typically prevent lawyers from documenting the scientific depredations and their rebuttals. Sadly, unlike litigations such as those involving Bendectin and silicone, the chronicles of fraud and exaggeration are mostly closed books in closed files in closed offices. These examples need the light of day and a fresh breeze to disseminate them widely in both the scientific and legal communities, so that all may have a healthy appreciation for the value of appropriately conducted studies generated in litigation contexts.

As I have intimated elsewhere, the welding fume litigation is a great example of specious claiming, which ultimately was unhorsed by publications inspired or funded by the defense. In the typical welding fume case, plaintiff claimed that exposure to manganese in welding fume caused Parkinson’s disease or manganism. Although manganism sounds as though it must be a disease that can be caused only by manganese, in the hands of plaintiffs’ expert witnesses, manganism became whatever ailment plaintiffs claimed to have suffered. Circularity and perfect definitional precision were achieved by semantic fiat.

The Sanchez-Ramos Meta-Analysis

Manganese Madness was largely the creation of the Litigation Industry, under the dubious leadership of Dickie Scruggs & Company. Although the plaintiffs enjoyed a strong tail wind in the courtroom of an empathetic judge, they had difficulties in persuading juries and ultimately decamped from MDL 1535, in favor of more lucrative targets. In their last hurrah, however, plaintiffs retained a neurologist, Juan Sanchez-Ramos, who proffered a biased, invalid synthesis, which he billed as a meta-analysis11.

Sanchez-Ramos’s meta-analysis, such as it was, provoked professional disapproval and criticism from the defense expert witness, Dr. James Mortimer. Because the work product of Sanchez-Ramos was first disclosed in deposition, and not in his Rule 26 report, Dr. Mortimer undertook belatedly a proper meta-analysis.12 Even though Dr. Mortimer’s meta-analysis was done in response to the Sanchez-Ramos’s improper, tardy disclosure, the MDL judge ruled that Mortimer’s meta-analysis was too late. The effect, however, of Mortimer’s meta-analysis was clear in showing that welding had no positive association with Parkinson’s disease outcomes. The MDL 1535 resolved quickly thereafter, and with only slight encouragement, Dr. Mortimer published a further refined meta-analysis with two other leading neuro-epidemiologists. See James Mortimer, Amy Borenstein, and Lorene Nelson, “Associations of welding and manganese exposure with Parkinson disease: Review and meta-analysis,” 79 Neurology 1174 (2012). See also Manganese Meta-Analysis Further Undermines Reference Manual’s Toxicology Chapter(Oct. 15, 2012).

1 See, e.g., David Michaels & Celeste Monforton, “Manufacturing Uncertainty Contested Science and the Protection ofthe Public’s Health and Environment,” 95 Am. J. Pub. Health S39, S40 (2005); David Michaels & Celeste Monforton, “How Litigation Shapes the Scientific Literature: Asbestos and Disease Among Automobile Mechanics,” 15 J. L. & Policy 1137, 1165 (2007). Michaels had served as a plaintiffs’ paid expert witness in chemical exposure litigation, and Monforton had been employed by labor unions before these papers were published, without disclosure of conflicts.

2 Leslie Boden & David Ozonoff, “Litigation-Generated Science: Why Should We Care?” 116 Envt’l Health Persp. 121, 121 (2008) (arguing that systematic distortion of the scientific record will result from litigation-sponsored papers even with disclosure of conflicts of interest). Ozonoff had served as a hired plaintiffs’ expert witnesses on multiple occasion before the publication of this article, which was unadorned by disclosure.

3 Lennart Hardell, Martin J. Walker, Bo Walhjalt, Lee S. Friedman, and Elihu D. Richter, “Secret Ties to Industry and Conflicting Interest in Cancer Research,” 50 Am. J. Indus. Med. 227, 233 (2007) (criticizing “powerful industrial interests” for “undermining independent research on hazard and risk,” in a “red” journal that is controlled by allies of the lawsuit industry). Hardell was an expert witness for plaintiffs in mobile phone litigation in which plaintiffs claimed that non-ionizing radiation caused brain cancer. In federal litigation, Hardell was excluded as an expert witness when his proffered opinions were found to be scientifically unreliable. Newman v. Motorola, Inc., 218 F. Supp. 2d. 769, 777 (D. Md. 2002), aff’d, 78 Fed. Appx. 292 (4th Cir. 2003).

4 See David Egilman & Susanna Bohme, “IJOEH and the Critique of Bias,” 14 Internat’l J. Occup. & Envt’l Health 147, 148 (2008) (urging a Marxist critique that industry-sponsored research is necessarily motivated by profit considerations, and biased in favor of industry funders). Although Egilman usually gives a disclosure of his litigation activities, he typically characterizes those activities as having been for both plaintiffs and defendants, even though his testimonial work for defendants is minuscule.

5 Kenneth J. Rothman, “Conflict of Interest: The New McCarthyism in Science,” 269 J. Am. Med. Ass’n 2782 (1993).

6 See Charles H. Hennekens, I-Min Lee, Nancy R. Cook, Patricia R. Hebert, Elizabeth W. Karlson, Fran LaMotte; JoAnn E. Manson, and Julie E. Buring, “Self-reported Breast Implants and Connective- Tissue Diseases in Female Health Professionals: A Retrospective Cohort Study, 275 J. Am. Med. Ass’n 616-19 (1998) (analyzing established cohort for claimed associations, with funding from the National Institutes of Health and Dow Corning Corporation).

7 See Barbara Hulka, Betty Diamond, Nancy Kerkvliet & Peter Tugwell, “Silicone Breast Implants in Relation to Connective Tissue Diseases and Immunologic Dysfunction: A Report by a National Science Panel to the Hon. Sam Pointer Jr., MDL 926 (Nov. 30, 1998).” The court-appointed expert witnesses dedicated a great deal of their professional time to their task of evaluating the plaintiffs’ claims and the evidence. At the end of the process, they all published their litigation work in leading journals. See Barbara Hulka, Nancy Kerkvliet & Peter Tugwell, “Experience of a Scientific Panel Formed to Advise the Federal Judiciary on Silicone Breast Implants,” 342 New Engl. J. Med. 812 (2000); Esther C. Janowsky, Lawrence L. Kupper., and Barbara S. Hulka, “Meta-Analyses of the Relation between Silicone Breast Implants and the Risk of Connective-Tissue Diseases,” 342 New Engl. J. Med. 781 (2000); Peter Tugwell, George Wells, Joan Peterson, Vivian Welch, Jacqueline Page, Carolyn Davison, Jessie McGowan, David Ramroth, and Beverley Shea, “Do Silicone Breast Implants Cause Rheumatologic Disorders? A Systematic Review for a Court-Appointed National Science Panel,” 44 Arthritis & Rheumatism 2477 (2001).

8 Stuart Bondurant, Virginia Ernster, and Roger Herdman, eds., Safety of Silicone Breast Implants (Institute of Medicine) (Wash. D.C. 1999).

9 See also Lester Brickman, “On the Applicability of the Silica MDL Proceeding to Asbestos Litigation, 12 Conn. Insur. L. J. 289 (2006); Lester Brickman, “Disparities Between Asbestosis and Silicosis Claims Generated By Litigation Screenings and Clinical Studies,” 29 Cardozo L. Rev. 513 (2007).

10 This apt phraseology is due to the late Keith Morgan, whose wit, wisdom, and scientific acumen are greatly missed. See W. Keith C. Morgan, “Meretricious Mensuration,” 6 J. Eval. Clin. Practice 1 (2000).

11 See Deposition of Dr. Juan Sanchez-Ramos, in Street v. Lincoln Elec. Co., Case No. 1:06-cv-17026, 2011 WL 6008514 (N.D. Ohio May 17, 2011).

12 See Deposition of Dr. James Mortimer, in Street v. Lincoln Elec. Co., Case No. 1:06-cv-17026, 2011 WL 6008054 (N.D. Ohio June 29, 2011).

Every Time a Bell Rings

July 1st, 2017

“Every time a bell rings, an angel gets his wings.”
Zuzu Bailey

And every time a court issues a non-citable opinion, a judge breaks fundamental law. Whether it wants to or not, a common law court, in deciding a case, creates precedent, and an expectation and a right that other, similarly situated litigants will be treated similarly. Deciding a case and prohibiting its citation deprives future litigants of due process and equal protection of the law. If that makes for more citable opinions, more work for judges and litigants, so be it; that is what our constitution requires.

Back in 2015, Judge Bernstein issued a ruling in a birth defects case in which the mother had claimed to have taken sertraline during pregnancy and this medication use caused her child to be born with congenital malformations. Applying what Pennsylvania courts insist is a Frye standard, Judge Bernstein excluded the proffered expert witness testimony that attempted to draw a causal connection between the plaintiff’s birth defect and the mother’s medication use. Porter v. SmithKline Beecham Corp., No. 03275, 2015 WL 5970639 (Phila. Cty. Pennsylvania, Ct. C.P. October 5, 2015) (Mark I. Bernstein, J.) Judge Bernstein has since left the bench, but he was and is a respected commentator on Pennsylvania evidence1, even if he was generally known for his pro-plaintiff views on many legal issues. Bernstein’s opinion in Porter was a capable demonstration of how Pennsylvania’s Frye rule can be interpreted to reach essentially the same outcome that is required by Federal Rule of Evidence 702. SeeDemonstration of Frye Gatekeeping in Pennsylvania Birth Defects Case” (Oct. 6, 2015); In re Zoloft Prod. Liab. Litig., No. 16-2247 , __ F.3d __, 2017 WL 2385279 , 2017 U.S. App. LEXIS 9832 (3d Cir. June 2, 2017) (affirming exclusion of dodgy statistical analyses and opinions, and the trial court’s entry of summary judgment on claims that sertraline causes birth defects).

In May of this year, the Pennsylvania Superior Court affirmed Judge Bernstein’s judgment, and essentially approved and adopted his reasoning. Porter v. SmithKline Beecham Corp., No. 3516 EDA 2015,2017 WL 1902905 (Pa. Super. May 8, 2017). What the Superior Court purport to giveth, the Superior Court taketh away. The Porter decision is franked as a “Non-Precedential Decision – See Superior Court I.O.P. 65.37.”

What is this Internal Operating Procedure that makes the Superior Court think that it can act and decide cases without creating precedent? Here is the relevant text from the Pennsylvania Code:

  1. An unpublished memorandum decision shall not be relied upon or cited by a Court or a party in any other action or proceeding, except that such a memorandum decision may be relied upon or cited
  1. when it is relevant under the doctrine of law of the case, res judicata, or collateral estoppel, and
  1. when the memorandum is relevant to a criminal action or proceeding because it recites issues raised and reasons for a decision affecting the same defendant in a prior action or proceeding.

210 Pa. Code § 65.37. Unpublished Memoranda Decisions. So, in other words, it is secret law.

No citation and no precedent rules are deeply problematic, and have attracted a great deal of scholarly attention2. And still, courts engage in this problematic practice. Prohibiting citation of Superior Court decisions in Pennsylvania is especially problematic in a state in which the highest court hears relatively few cases, and where the Justices involve themselves in internecine disputes. As other commentators have noted, prohibiting citation to prior decisions admitting or excluding expert witness testimony stunts the development of an area of evidence law, in which judges and litigants are often confused and in need of guidance. William E. Padgett, “‘Non-Precedential’ Unpublished Decisions in Daubert and Frye Cases, Often Silenced,” Nat’l L. Rev. (2017). The abuses of judge-made secret law from uncitable decisions has been abolished in the federal appeals courts for over a decade3. It is time for the state courts to follow suit.

1 See, e.g., Mark I. Bernstein, Pennsylvania Rules of Evidence (2017).

See Erica Weisgerber, “Unpublished Opinions: A Convenient Means to an Unconstitutional End,” 97 Georgetown L.J. 621 (2009);  Rafi Moghadam, “Judge Nullification: A Perception of Unpublished Opinions,” 62 Hastings L.J. 1397 (2011);  Norman R. Williams, “The failings of Originalism:  The Federal Courts and the Power of Precedent,” 37 U.C.. Davis L. Rev.761 (2004);  Dione C. Greene, “The Federal Courts of Appeals, Unpublished Decisions, and the ‘No-Citation Rule,” 81 Indiana L.J. 1503 (2006);  Vincent M. Cox, “Freeing Unpublished Opinions from Exile: Going Beyond the Citation Permitted by Proposed Federal Rule of Appellate Procedure 32.1,” 44 Washburn L.J. 105 (2004);  Sarah E. Ricks, “The Perils of Unpublished Non-Precedential Federal Appellate Opinions: A Case Study of The Substantive Due Process State-Created Danger Doctrine in One Circuit,” 81 Wash. L.Rev. 217 (2006);  Michael J. Woodruff, “State Supreme Court Opinion Publication in the Context of Ideology and Electoral Incentives.” New York University Department of Politics (March 2011);  Michael B. W. Sinclair, “Anastasoff versus Hart: The Constitutionality and Wisdom of Denying Precedential Authority to Circuit Court Decisions”; Thomas Healy, “Stare Decisis as a Constitutional Requirement,” 104 W. Va. L. Rev. 43 (2001); David R. Cleveland & William D. Bader, “Precedent and Justice,” 49 Duq. L. Rev. 35 (2011); Johanna S. Schiavoni, “Who’s Afraid of Precedent,” 49 UCLA L. Rev. 1859 (2002); Salem M. Katsh and Alex V. Chachkes, “Constitutionality of ‘No-Citation’ Rules,” 3 J. App. Prac. & Process 287 (2001); David R. Cleveland, “Appellate Court Rules Governing Publication, Citation, and Precedent of Opinions: An Update,” 16 J. App. Prac. & Process 257 (2015). See generally The Committee for the Rule of Law (website) (collecting scholarship and news on the issue of unpublished and supposedly non-precedential opinions). The problem even has its own Wikipedia page. SeeNon-publication of legal opinions in the United States.”

3 See Fed. R. App. Proc. 32.1 (prohibiting federal courts from barring or limiting citation to unpublished federal court opinions, effective after Jan. 1, 2007).

Talc Litigation Supported by Slippery Expert Witness

April 25th, 2017

Another day, another talc trial in Missouri. This one involves Lois Slemp, who sued Johnson & Johnson and its talc supplier, Imerys Talc America Inc., on her claim that her long-term use of talc caused her to develop borderline ovarian cancer.

To support her causal claim, Slemp’s lawyers called upon Dr. Daniel Cramer, a gynecologist and epidemiologist, from Harvard, to testify. See Daniel Siegal, “J & J’s Talc Caused Woman’s Cancer, Harvard MD Tells Jury,” Law360 (April 24, 2017) [cited as Siegel]. At first blush, counsel’s retention of Dr. Cramer seems like a brilliant choice. Cramer is a Professor of Epidemiology, at Harvard University’s T.H. Chan School Of Public Health, and a Professor of Obstetrics, Gynecology and Reproductive Biology, at Harvard Medical School. For over 30 years, Cramer has published primary studies, reviews, and commentary pieces in which he has addressed the epidemiologic and biological evidence involving talc and ovarian cancer.1

Cramer, as both a physician and an epidemiologist, addressed both general and specific causation in the Slemp case. Notwithstanding Slemp’s risk factors of family history of cancer and obesity, Cramer asserted with “reasonable degree of medical and scientific certainty” that talc was “the major contributing cause and substantial cause in the development of her serious borderline tumor.” Siegel, supra.

Somehow this physician epidemiologist has taken a putative risk factor and converted it into the cause. This conversion would perhaps make sense if the risk factor were necessary or sufficient to cause the outcome, but the evidence involving talc and ovarian cancer does not even remotely resemble such a situation. The epidemiologic evidence is weak and inconsistent, but if causation were assumed on the basis of cherry-picked studies, the relative risk for ovarian cancer would be somewhere around 1.2. Somewhat like the magic grits in My Cousin Vinny, Dr. Cramer has found a putative risk factor that blocks out all other risk factors, including the idiopathic, baseline risks that afflict all women in the age range of Ms. Slemp.

On cross-examination, Cramer was confronted with his failure to have asserted general causation in his professional, peer-reviewed publications on talc and ovarian cancer. Defense counsel Orlando Richmond drew the jury’s attention to an invidious comparison between Cramer’s courtroom assertions and his epistemically more modest conclusions and qualifications in the scientific literature, in which he never claimed a causal relationship between talc use and ovarian cancer:

Q. “Nowhere in the published scientific literature, did you or your colleagues, ever publish, ever publish, that genital talc use causes serious borderline tumors, the disease Ms. Slemp has. Isn’t that a correct statement, sir?”

A. “We certainly made a powerful case for there being an association. We may not have used the word ‘causal,’ if I had known how important that word was, I would have used it a long time ago.”


Wow! A Harvard professor of medicine and epidemiology, who teaches at the Harvard School of Public Health, and who labored in the field of epidemiology for over three decades, was unaware until earlier this week, when he darkened the doorway of a Missouri courtroom, that there was an important distinction between association and causation, and this distinction was crucial to discussions and debates in science and public policy.

Now that is slipperier than the most lubricious talc dusting. Why would such an accomplished physician scientist equivocate so? Perhaps Cramer refrained from drawing a causal conclusion because uncertainty favored obtaining future grants to study the same issue. Maybe he refrained from drawing a causal conclusion because doing so would have made him subject to criticism, ridicule, and rebuttal from his professional colleagues. I cannot think of a flattering reason for Cramer’s timidity in expressing himself clearly to his professional peers over the course of 34 years of researching the issues.

Previously, I have called attention to “white hat” bias in the courtroom, which occurs when scientists enter the fray based upon their distorted perceptions of siding with the “little guy” in a misguided quest for social justice. Cramer’s participation in the litigation process illustrates another kind of bias in play in courtrooms. After 30 years of publishing on talc and ovarian cancer, Cramer has failed to obtain acceptance of a claim for causality from the scientific community, but the courtroom is a venue where he can obtain the approving judgment of a scientifically naïve jury or judge and thus gain some vindication for his work that has gone unappreciated by professional colleagues and policy makers.

1 See, e.g., Daniel W. Cramer, et al., “The Association Between Talc Use and Ovarian Cancer: A Retrospective Case-Control Study in Two U.S. States,” 27 Epidemiology 334 (2016); Daniel W. Cramer, “The epidemiology of endometrial and ovarian cancer,” 26 Hematol. Oncol. 1 (2012); M. A. Gates, Daniel W. Cramer, et al., “Talc use, variants of the GSTM1, GSTT1, and NAT2 genes, and risk of epithelial ovarian cancer,” 17 Cancer Epidemiol. Biomarkers Prevention 2436 (2008); Joshua Muscat, M. Huncharek, and Daniel W. Cramer, “Talc and anti-MUC1 antibodies,” 14 Cancer Epidemiol Biomarkers Prevention 2679 (2005); Daniel W. Cramer, et al., “Presence of talc in pelvic lymph nodes of a woman with ovarian cancer and long-term genital exposure to cosmetic talc,” 110 Obstet. & Gynecol. 498 (2007); D. M. Gertig, Daniel W. Cramer, Graham A. Colditz, et al., “Prospective study of talc use and ovarian cancer,” 92 J. Nat’l Cancer Inst. 249 (2000); Daniel W. Cramer, “Perineal talc exposure and subsequent epithelial ovarian cancer: a case-control study,” 94 Obstet. & Gynecol. 160 (1999); Daniel W. Cramer, et al., “Genital talc exposure and risk of ovarian cancer,” 81 Internat’l J. Cancer 351 (1999); Bernard L. Harlow, Daniel W. Cramer, et al., “Perineal exposure to talc and ovarian cancer risk,” 80 Obstet. & Gynecol. 19 (1992); Daniel W. Cramer, et al., “Ovarian cancer and talc: a case-control study, 50 Cancer 372 (1982).

Traditional, Frequentist Statistics Still Hegemonic

March 25th, 2017

The Defense Fallacy

In civil actions, defendants, and their legal counsel sometimes argue that the absence of statistical significance across multiple studies requires a verdict of “no cause” for the defense. This argument is fallacious, as can be seen where there are many studies, say eight or nine, which all consistently find elevated risk ratios, but with p-values slightly higher than 5%. The probability that eight studies, free of bias, would consistently find an elevated risk ratio, regardless of the individual studies’ p-values, is itself very small. If the studies were amenable to meta-analysis, the summary estimate of the risk ratio would itself likely be highly statistically significant in this hypothetical.

The Plaintiffs’ Fallacy

The plaintiffs’ fallacy derives from instances, such as the hypothetical one above, in which statistical significance, taken as a property of individual studies, is lacking. Even though we can hypothesize such instances, plaintiffs fallaciously extrapolate from them to the conclusion that statistical significance, or any other measure of sampling estimate precision, is unnecessary to support a conclusion of causation.

In courtroom proceedings, epidemiologist Kenneth Rothman is frequently cited by plaintiffs as having shown or argued that statistical significance is unimportant. For instance, in the Zoloft multi-district birth defects litigation, plaintiffs argued in a motion for reconsideration of the exclusion of their epidemiologic witness that the trial court had failed to give appropriate weight to the Supreme Court’s decision in Matrixx Initiatives, Inc. v. Siracusano, 563 U.S. 27 (2011), as well as to the Third Circuit’s invocation of the so-called “Rothman” approach in a Bendectin birth defects case, DeLuca v. Merrell Dow Pharms., Inc., 911 F.2d 941 (3d Cir. 1990). According to the plaintiffs’ argument, their excluded epidemiologic witness, Dr. Anick Bérard, had used this approach in arriving at her novel conclusion that sertraline causes virtually every kind of birth defect.

The Zoloft plaintiffs did not call Rothman as a witness; nor did they even present an expert witness to explain what Rothman’s arguments were. Instead, the plaintiffs’ counsel, sneaked in some references and vague conclusions into their cross-examinations of defense expert witnesses, and submitted snippets from Rothman’s textbook, Modern Epidemiology.

If plaintiffs had called Dr. Rothman to testify, he would have probably insisted that statistical significance is not a criterion for causation. Such insistence is not as helpful to plaintiffs in cases such as Zoloft birth defects cases as their lawyers might have thought or hoped. Consider for instance the cases in which causal inferences are arrived at without formal statistical analysis. These instances are often not relevant to mass tort litigation that involve prevalent exposure and a prevalent outcome.

Rothman also would have likely insisted that consideration of random variation and bias are essential to the assessment of causation, and that many apparently or nominally statistically significant associations do not and cannot support valid inferences of causation. Furthermore, he might have been given the opportunity to explain that his criticisms of significance testing are as much directed to the creation of false positive as to false negative rates in observational epidemiology. In keeping with his publications, Rothman would have challenged strict significance testing with p-values as opposed to the use of sample statistical estimates in conjunction with confidence intervals. The irony of the Zoloft case and many other litigations was that the defense was not using significance testing in the way that Rothman had criticized; rather the plaintiffs were over-endorsing statistical significance that was nominal, plagued by multi-testing, and inconsistent.

Judge Rufe, who presided over the Zoloft MDL, pointed out that the Third Circuit in DeLuca had never affirmatively endorsed Professor Rothman’s “approach,” but had reversed and remanded the Bendectin case to the district court for a hearing under Rule 702:

by directing such an overall evaluation, however, we do not mean to reject at this point Merrell Dow’s contention that a showing of a .05 level of statistical significance should be a threshold requirement for any statistical analysis concluding that Bendectin is a teratogen regardless of the presence of other indicia of reliability. That contention will need to be addressed on remand. The root issue it poses is what risk of what type of error the judicial system is willing to tolerate. This is not an easy issue to resolve and one possible resolution is a conclusion that the system should not tolerate any expert opinion rooted in statistical analysis where the results of the underlying studies are not significant at a .05 level.”

2015 WL 314149, at *4 (quoting from DeLuca, 911 F.2d at 955). And in DeLuca, after remand, the district court excluded the DeLuca plaintiffs’ expert witnesses, and granted summary judgment, based upon the dubious methods employed by plaintiffs’ expert witnesses (including the infamous Dr. Done, and Shanna Swan), in cherry picking data, recalculating risk ratios in published studies, and ignoring bias and confounding in studies. On subsequent appeal, the Third Circuit affirmed the judgment for Merrell Dow. DeLuca v. Merrell Dow Pharma., Inc., 791 F. Supp. 1042 (3d Cir. 1992), aff’d, 6 F.3d 778 (3d Cir. 1993).

Judge Rufe similarly rebuffed the plaintiffs’ use of the Rothman approach, their reliance upon Matrixx, and their attempt to banish consideration of random error in the interpretation of epidemiologic studies. In re Zoloft (Sertraline Hydrochloride) Prods. Liab. Litig., MDL No. 2342; 12-md-2342, 2015 WL 314149 (E.D. Pa. Jan. 23, 2015) (Rufe, J.) (denying PSC’s motion for reconsideration). SeeZoloft MDL Relieves Matrixx Depression” (Feb. 4, 2015).

Some Statisticians’ Errors

Recently, Dr. Rothman and three other epidemiologists set out to track the change, over time, from 1975 to 2014, of the use of various statistical methodologies. Andreas Stang, Markus Deckert, Charles Poole & Kenneth J. Rothman, “Statistical inference in abstracts of major medical and epidemiology journals 1975–2014: a systematic review,” 32 Eur. J. Epidem. 21 (2017) [cited below as Stang]. They made clear that their preferred methodological approach was to avoid the strictly dichotomous null hypothesis significance testing (NHST), which has evolved from Fisher’s significance testing and Neyman’s null hypothesis testing (NHT), in favor of the use of estimation with confidence intervals (CI). The authors conducted a meta-study, that is a study of studies, to track the trends in use of NHST, ST, NHT and CI reporting in the major bio-medical journals.

Unfortunately, the authors limited their data and analysis to abstracts, which makes their results very likely misleading and incomplete. Even when abstracts reported using so-called CI-only approaches, the authors may well have reasoned that point estimates with CIs that spanned no association were “non-significant.” Similarly, authors who found elevated risk ratios with very wide confidence intervals may well have properly acknowledged that their study did not provide credible evidence of an association. See W. Douglas Thompson, “Statistical criteria in the interpretation of epidemiologic data,” 77 Am. J. Public Health 191, 191 (1987) (discussing the over-interpretation of skimpy data).

Rothman and colleagues found that while a few epidemiologic journals had a rising prevalence of CI-only reports in abstracts, for many biomedical journals the NHST approach remained more common. Interestingly, at three of the major clinical medical journals, the Journal of the American Medical Association, the New England Journal of Medicine, and Lancet, the NHST has prevailed over the almost four decades of observation.

The clear implication of Rothman’s meta-study is that consideration of significance probability, whether or not treated as a dichotomous outcome, and whether or not treated as a p-value or a point estimate with a confidence interval, is absolutely critical to how biomedical research is conducted, analyzed, and reported. In Rothman’s words:

Despite the many cautions, NHST remains one of the most prevalent statistical procedures in the biomedical literature.”

Stang at 22. See also David Chavalarias, Joshua David Wallach, Alvin Ho Ting & John P. A. Ioannidis, “Evolution of Reporting P Values in the Biomedical Literature, 1990-2015,” 315 J. Am. Med. Ass’n 1141 (2016) (noting the absence of the use of Bayes’ factors, among other techniques).

There is one aspect to the Stang article that is almost Trump-like in its citing to an inappropriate, unknowledgable source and then treating its author as having meaningful knowledge of the subject. As part of their rhetorical goals, Stang and colleagues declare that:

there are some indications that it has begun to create a movement away from strict adherence to NHT, if not to ST as well. For instance, in the Matrixx decision in 2011, the U.S. Supreme Court unanimously ruled that admissible evidence of causality does not have to be statistically significant [12].”

Stang at 22. Whence comes this claim? Footnote 12 takes us to what could well be fake news of a legal holding, an article by a statistician about a legal case:

Joseph L. Gastwirth, “Statistical considerations support the Supreme Court’s decision in Matrixx Initiatives v. Siracusano, 52 Jurimetrics J. 155 (2012).

Citing a secondary source when the primary source is readily available, and what is at issue, seems like poor scholarship. Professor Gastwirth is a statistician, not a lawyer, and his exegesis of the Supreme Court’s decision is wildly off target. As any first year law student could discern, the Matrixx case could not have been about the admissibility of evidence because the case had been dismissed on the pleadings, and no evidence had ever been admitted or excluded. The only issue on appeal was the adequacy of the allegations, not the admissibility of evidence.

Although the Court managed to muddle its analysis by wandering off into dicta about causation, the holding of the case is that alleging causation was not required to plead a case of materiality for a securities fraud case. Having dispatched causality from the case, the Court had no serious business in setting the considerations for alleging in pleadings or proving at trial the elements of causation. Indeed, the Court made it clear that its frolic and detour into causation could not be taken seriously:

We need not consider whether the expert testimony was properly admitted in those cases [cited earlier in the opinion], and we do not attempt to define here what constitutes reliable evidence of causation.”

Matrixx Initiatives, Inc. v. Siracusano, 563 U.S. 27, 131 S.Ct. 1309, 1319 (2011).

The word “admissible” or “admissibility” never appear in the Court’s opinion, and the above quote explains that the admissibility was not considered. Laughably, the Court went on to cite three cases as examples of supposed causation opinions in the absence of statistical significance. Two of the three were specific causation, differential etiology cases that involved known general causation. The third case involved a claim of birth defects from contraceptive jelly, when the plaintiffs’ expert witnesses actually relied upon statistically significant (but thoroughly flawed and invalid) associations.1

When it comes to statistical testing the legal world would be much improved if lawyers actually and carefully read statistics authors, and if statisticians and scientists actually read court opinions.