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Evidence-Based Medicine and the Law

The Courts Confront Clinical Practice Guidelines

Special issue contains articles from expert meeting, 'Evidence: Its Meanings and Uses in Law, Medicine and Health Care.

By Arnold J. Rosoff, University of Pennsylvania

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The Advent of Evidence-Based Medicine
   The Law's Acceptance of Evidence-Based Medicine
   The Uses of Medical Evidence in the Courts
   Problems with New Tools
Clinical Practice Guidelines in the Courts
   The Importance of Federal Law
   Admissibility and Weight Given to Clinical Practice Guidelines
   Courts' Experience with Clinical Practice Guidelines
   Who Can Use Guidelines and for What Purpose?
   The Problem of Conflicting Guidelines
The "Politics" of Clinical Practice Guidelines
   Knowing and Acting in Medical Practice
   The Technocratic Wish
   The Implications of the Political Terrain
A Certification Program for Clinical Practice Guidelines?
Basic Concept and Operation of the Certification Program
   Who Should Do the Certifying?
   Should Certification Be Mandatory or Voluntary?
   The Criteria for Certification
   The Significance of Certification
   The Costs of a Certification Program
   The Challenges of Implementation
References and Notes



This article examines how courts are likely to apply evidence-based medicine, and particularly clinical practice guidelines (CPGs), in healthcare litigation involving quality-of-care and entitlement-to-benefits (coverage) claims. Exploring the "politics" of the current situation, it observes that, just as clinicians have been reluctant to use CPGs in practice, courts have been, and likely will continue to be, slow to apply them in deciding cases. The article analyzes extant and proposed statutory approaches to legitimizing and promoting courts' use of CPGs. It concludes by renewing the author's earlier and controversial proposal to establish a voluntary federal program for certifying guidelines and directing courts to give certified CPGs greater weight in healthcare litigation.

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The Advent of Evidence-Based Medicine

The past few decades have seen tremendous and exciting strides in the development of evidence-based medicine (EBM), defined as the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients (see Cynthia D. Mulrow and Kathleen N. Lohr in this issue).1 Medicine, long recognized as a subtle admixture of science and art, has moved notably in the direction of an exact science as new tools and techniques have been developed to help practitioners of "the healing arts" understand better what works in the treatment of patients. This dramatic expansion of medical knowledge, and of the ways by which medical knowledge is advanced, is changing the face of medical practice.

A key aspect of this change has been the development of outcomes research, for systematic and large-scale study of the effects different diagnostic tools or therapies have when applied to large numbers of patients (see U.S. Congress 1994; Roper et al. 1988; Havighurst 1990). Facilitated by the widespread use of computers to record and analyze medical data and the standardization of encounter and treatment data, outcomes research is increasingly making it possible to know more precisely and certainly what is, and is not, effective therapy.

Many in the health care community have welcomed this advance of knowledge, but some see a potential downside for professional autonomy. When more is known about the "right" way to treat a particular condition, there is less latitude for individual judgment. Clinicians, historically accorded wide latitude for the exercise of personal discretion in choosing treatments for their patients, now feel increasing pressure to conform to established norms of treatment. Much of that pressure comes from managed care organizations (MCOs) and health plans, both private and governmental, all pursuing an agenda of aggressive cost containment. Moreover, in an environment supportive of EBM, a clinician might more readily be held accountable for a poor outcome if it can be attributed to deviation from an EBM-based prescribed treatment approach. For this reason, EBM is seen by some as packing a one-two punch: erosion of autonomy going into a treatment situation accompanied by greater risk of liability after the fact. It's no wonder, then, that some parts of the medical community view EBM as a mixed blessing.

A major way that EBM has impacted medical practice has been through the development, dissemination, and use of clinical practice guidelines (CPGs). The Institute of Medicine's widely cited 1990 report defines CPGs as "systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances" (Field and Lohr 1990). CPGs can be used to guide practitioners in undertaking treatment of various kinds of conditions and to help third-party payers, regulatory bodies, and courts determine whether care given in a particular instance was adequate and appropriate. Thus CPGs have relevance both for the practice of medicine by physicians and for the regulation of that practice by others.

A brief word about terminology: Because CPGs are the most common practical embodiment of EBM, the terms "clinical practice guidelines" and "evidence-based medicine" and their acronyms have often been used interchangeably, or nearly so. Daniel W. Shuman's essay in this symposium issue treats them this way; this article will too. It should be understood, however, that they are distinct terms and can be used in contexts where they are not interchangeable. EBM can show up in forms other than CPGs—for example, in journal articles, unpublished studies, and expert testimony. Conversely, CPGs are not necessarily based upon EBM—although the vast majority of the CPGs being generated nowadays are, or at least purport to be. Cynthia Mulrow and Kathleen Lohr's essay recognizes that guidelines generated primarily through a professional consensus process—the traditional approach—may differ from those based more directly on hard, empirical evidence—the EBM approach. This last point is especially important, because courts, in deciding what weight to accord to CPGs, may find it useful, even necessary, to distinguish between those that are based on EBM and those that are not.

Building on professional reservations about EBM generally, growth in the development and use of CPGs has fueled concern in some quarters about their implications for medical practice. Some decry the spread of CPGs as the advent of "cookbook medicine," having the potential to turn doctors into automatons and lower the quality of health care by subordinating and subverting professional skill and judgment. While many of the changes to be expected from EBM and CPGs are positive and should be welcomed and facilitated, the political climate for their acceptance, discussed below, is far from assured.

For the balance of this section, this essay lays a foundation by discussing in general terms how courts might benefit from the use of EBM, especially in the form of clinical practice guidelines, and by examining, again in general terms, why and how courts might have difficulty in adopting and using CPGs. In the second section, the essay examines various ways courts might employ CPGs in handling quality-of-care and entitlement-to-benefits cases. Courts' actual experience with litigation involving CPGs is highlighted, as is emerging legislation that defines how, and by whom, CPGs may be used in litigation. A third section explores the "politics" of EBM and CPGs, considering how political and cultural forces in the health care, legal, and public policy communities may bear upon the rules legislatures and courts apply to govern the use of this type of evidence. Finally, the essay concludes with a proposal I put forward some five years ago (Rosoff 1995) for the development of a governmental certification program for CPGs. The essential notion is that, in the face of multiple, competing guidelines for treating particular conditions, courts could benefit greatly from some mechanism, presumably governmental, that would help them sort credible and authoritative guidelines from those not so deserving of the courts' acceptance. While numerous factors, some of them "political," in different meanings of that term, cut against the establishment of a certification program, I continue to believe the idea has merit and deserves further consideration.

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The Law's Acceptance of Evidence-Based Medicine

In addition to professional reactions to EBM, how the law regards and treats EBM will also greatly affect the pace and nature of its acceptance. There are troubling indications that the courts haven't figured out yet how to deal with medical evidence in a variety of contexts. A great deal has been written about the distorting effects of "junk science" in litigation concerning silicon breast implants, various drugs and medical devices, such as Bendectin and IUDs, toxic torts, and other controversies involving scientific evidence. Popular books of the past few years—such as David Faigman's Legal Alchemy: The Use and Misuse of Science in the Law (1999) and Marcia Angell's Science on Trial: The Clash of Medical Evidence and the Law in the Breast Implant Case (1997)—raise disturbing doubts about how often the courts can "get it right" when dealing with evidence of this nature. The great promise of EBM to improve the quality of care, help contain health care costs, reduce disputes about coverage under health plans, and ease the financial and other burdens of medical malpractice litigation on the health care system may be compromised if the law is unsure or confused about how to deal with EBM.

How, then, can we move most effectively toward the adoption of desirable legal rules and procedures for dealing with evidence-based medicine? The traditional process of generating legal doctrine in a new area through litigation on an ad hoc, state-by-state basis, as cases happen to come up, is too haphazard and slow to be adequate for a matter as important, volatile, and fast-moving as the adoption and use of EBM. As noted above, this essay considers some approaches that have been tried in an effort to accelerate EBM's assimilation into the law and, toward that same end, offers the author's proposal for certification of clinical practice guidelines.

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The Uses of Medical Evidence in the Courts

In general, people are enthusiastic about the prospect of developing better tools that will enable them to do their jobs more efficiently and effectively. When faced with the reality of new tools, however, this enthusiasm often is diminished by the challenges of improving skill levels. Once a new tool is mastered, the investment in gearing up to use it may "pay for itself" many times over, either by saving future time and effort or by making possible a better product or service. In the short run, though, adoption of new approaches can generate more cost than benefit. This may well be the case with the emerging use of EBM by the courts. EBM applications may ultimately make it much easier for courts to resolve health care disputes; but, in the short run, the courts will have to learn new principles and develop new rules for applying them in the litigation context. There will undoubtedly be challenges to those rules. An important objective of the symposium that spawned these essays was to help assure that the legal system's balance sheet on EBM comes up positive at the earliest time possible.

To discuss how the legal system will treat new forms of medical evidence, it is necessary to recognize that such evidence is used by the courts in a number of different contexts. Within the frame of the present discussion, two main categories of use are relevant: challenges regarding the quality of care (the principal subject of medical malpractice litigation) and challenges regarding the determination of what benefits are covered under a health plan in a given instance. Federal courts have struggled for several years to sort out these two classes of issues in cases involving the scope of federal preemption under ERISA, the Employee Retirement Income Security Act of 1974 (29 United States Code 1001, et seq.) (see Dukes v. U.S. Healthcare, 57 F.3d 350 [3d Cir. 1995]; Mariner 1996, 2000). Under managed care, these two sets of issues, though historically separate, increasingly tend to be intertwined. With growing frequency, suits are filed claiming that the quality of care was inadequate because benefits owed under the plaintiff's health plan were withheld, either with or without the plaintiff's knowledge at the time. Both quality-of-care and coverage cases involve common issues that are typically addressed through the testimony of medical expert witnesses. The main issues commonly calling for expert testimony are: (1) the applicable standard of care, (2) causation (the connection between the alleged wrongful conduct and the harm suffered by the plaintiff), and (3) the assessment of damages, which often involves (4) medical prognosis.

The type of issue involved dictates the nature and scope of the expert witness's input. The last three of these issues—causation, assessment of damages, and prognosis—usually require the expert witness to apply his or her expertise directly to the question at hand.2 The first of the four issues, the standard of care, is different, however. On this point, an expert is supposed to testify not as to what she or he thinks is the proper way to treat the case at hand but, rather, as to what others in the profession commonly would do in such a situation. The expert's testimony is focused this way because courts usually measure the adequacy of a patient's treatment by its conformity to standard practice in the relevant medical community, the so-called professional community standard. Thus, in this context—different, perhaps, from all others in which medical experts are called to testify—the expert's contribution is not his own scientific judgment or expertise about how best to handle a clinical situation but, rather, his or her knowledge of how professional peers commonly handle similar situations. This difference in the treatment of standard-of-care issues is important to the present discussion because, as explained below, a court uses a CPG to establish the legal standard of care, obviating the need for expert testimony on that point. By contrast, even where a CPG contains information relevant to causation, assessment of damages, or prognosis, it is hard to see how a court could make use of this information without the accompanying testimony of a medical expert witness. For this reason, and because the main object of CPGs is to set a standard of care, the present discussion addresses only those situations where CPGs are used to help determine the legal standard of care to be applied in the case being litigated. Belying the assertion just made about what the main object of CPGs is, for reasons of professional politics and in contemplation of litigation, guidelines developers routinely disclaim that their recommendations are "standard-setting." Despite these protestations, it remains an open question whether, and to what extent, courts will treat CPGs as setting the legally required standard of care.

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Problems with New Tools

Will the explosion of medical evidence and CPGs be a help or a hindrance to the courts? On the one hand, better evidence might make it easier for courts to reach accurate determinations in a difficult technical area. On the other hand, the profusion of evidence, seemingly or actually inconsistent (e.g., conflicting clinical practice guidelines), could confuse more than clarify.

To illustrate with an example, imagine that a forty-five-year-old female HMO member loses a breast to cancer, which, she claims, could have been treated successfully if caught earlier by more frequent mammography screening. The HMO screened once every two years, following the guidelines of the National Cancer Institute (NCI) for women in her age and risk category. The patient-plaintiff rests her case on a contrary guideline, issued by the American Cancer Society (ACS), which calls for screening once a year for women in that category. The jury must decide whether the doctor and HMO met the standard of adequate care by screening on the less frequent schedule. Traditionally, before CPGs were such a part of the picture, the parties in a malpractice case would address this issue by having medical experts testify on each side as to the professional community standard—the classic "battle of the experts." Might the contest be raised now to a higher level, with the guideline of one respected professional group pitted against that of another? Will we now see a "battle of the super-experts?" Clark Havighurst (1991: 95), in his seminal early exploration of the use of guidelines, observed that "practice guidelines may only occasionally resolve a dispute crucial in the litigation of an actual malpractice claim." But, now that the guidelines movement has gathered another decade's worth of momentum, that may be changing. With CPGs routinely playing a central role in the determination of what care patients receive, it is easy to envision them assuming a more prominent role in fixing the legal standard for measuring the adequacy of that care—in other words, serving the evidentiary function traditionally served by live experts.

If CPGs do come to play a greater role in medical malpractice and related cases, might a court allow evidence and/or argument to the point that one guideline-generating organization was entitled to more respect than the other or that one set of guidelines was more credible because better supported by the underlying data or by a more robust methodology for outcomes research, possibly including cost-effectiveness analysis (CEA) (see Peter D. Jacobson and Matthew L. Kanna in this issue)? Might the court allow the parties to lead the jury through the mechanics and nuances of EBM research and guideline generation? Might one party try to show that, whereas its guideline was based on solid, up-to-date empirical data, its opponent's older guideline was developed through a more subjective, consensus-based process and, thus, was less valid? Such evidence, while it might fascinate a jury, would likely have great potential to confuse it. Under the principle of Daubert v. Merrell Dow Pharmaceuticals [509 U.S. 579 (1993)], as described in Shuman's article in this issue, a trial judge is required to prescreen scientific evidence and admit only that which is likely to inform the jury and not confound it. In pursuing this obligation, might the judge bar this entire line of inquiry? Might she simply make an initial determination as to whether each of the proffered CPGs was authoritative enough to be admitted and then let them go to the jury on equal footing even though she believed one to be notably more sound—i.e., better conceived or based on stronger science—or more reputationally authoritative than the other? It is clear that the court's job in managing health care litigation may be significantly more complex in the face of the better knowledge and evidence that EBM makes possible than it would have been previously in "less enlightened" times. (It should be noted that the Daubert ruling applies only in cases controlled by the Federal Rules of Civil Procedure and those in states that have adopted the principle of Daubert.)

Assuming, for the sake of argument, that a savvy trial judge understands enough about CPGs to make wise rulings about how they should be handled as evidence, there still is likely to be controversy around such rulings until they are validated on appeal. Novel procedural rulings, such as those involving the admissibility and significance of new kinds of evidence, routinely invite challenges. (As has happened before in health care, and other fields, courts may be hindered in reaching important substantive issues because they first have to formulate new definitional and procedural rules and have them tested and approved. Consider, for example, the protracted haranguing over the use and validity of DNA evidence in the criminal trial of O. J. Simpson.) An example of this phenomenon, addressed in the Shuman essay, is the treatment of expert testimony in litigation involving medical and scientific matters (e.g., products liability, toxic tort, etc.). Other examples in the health care field include cases involving contractual arbitration in health care (Madden v. Kaiser Foundation Hospitals, 552 P.2d 1178 [Cal. 1976]; Rosoff 1986) and the use of pretrial screening panels for medical malpractice cases (Macchiaroli 1990; Carlin 1980; Institute of Medicine 1978). Issues will inevitably arise as courts pick their way through the question of how to handle CPGs as evidence. Challenges will address not just the admissibility of and weight to be accorded to CPGs but also whether the use of CPGs is allowed to both plaintiffs and defendants on an equal basis, an issue discussed below.

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Page last reviewed April 2001
Internet Citation: Evidence-Based Medicine and the Law: The Courts Confront Clinical Practice Guidelines. April 2001. Agency for Healthcare Research and Quality, Rockville, MD.


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