Intended for healthcare professionals

Long version

How does evidence based guidance influence determinations of medical negligence?
Brian Hurwitz
School of Humanities, King’s College, London WC2R 2LS
Brian Hurwitz
professor of medicine and the arts

“Any doctor not fulfilling the standards and quality of care in the appropriate treatment that are set out in these Clinical Guidelines, will have this taken into account if, for any reason, consideration of their performance in this clinical area is undertaken.” Department of Health, 1999.(1)

Evidence based guidance arguably offers the most trustworthy advice available to clinicians concerning medical management. Their authoritative status may explain why clinical guidelines are sometimes prefaced with vague warnings that link guideline compliance with accountability. But how authoritative can guidelines actually be, and does evidence based guidance entirely supplant clinical discretion?

The legal status of evidence based guidance is examined, including whether guidelines from the National Institute for Clinical Excellence (NICE) should be understood to carry special importance in helping courts to decide whether or not allegations of negligence should be upheld.

What is evidence?
Evidence is a generic notion of great importance to many practices and enquiries. Cardinal to spying, journalism, historical and scientific research, and the practice of medicine, semantically the term bundles together two approaches to supporting belief, perception, and understanding. Whether evidence refers to marks or indications conspicuous to an observer, to reasoning and judgment about such indications, or to analysis of data arising from experiments, evidence leads on to and supports hypotheses and conclusions, however provisional and conditional.

Evidence—and the more recently minted compound term “evidence based”—refers to reliable observational, inferential, or experimental information forming part of the grounds for upholding or rejecting claims or beliefs. Evidence based medicine (EBM) has not developed a new concept of evidence(2); its major contribution lies in the emphasis it places on a hierarchy of evidential reliability, in which conclusions related to evidence from controlled experiments are accorded greater credibility than conclusions grounded in other sorts of evidence. Since studies underpinning most medical practices are generally of very variable design and quality—experimental, controlled, blinded or unblinded, uncontrolled, observational, ecological, cross sectional, prospective, retrospective, qualitative, and others—recommendations synthesised from such studies are themselves very variably related to evidence.

Evidence based guidelines claim to be authoritative in the sense of embodying a combination of best evidence and judgment, designed to ensure that recommendations are valid and reliable. For guidance to be binding on clinicians it must be trustworthy.(3) But how trustworthy, clinically, can such guidance actually be? Take, for example, the 2003 UK evidence based guidelines for the management of asthma, which recommend intravenous infusion of 1.2 g of magnesium sulfate over 20 minutes for the treatment of severe life threatening asthma (level 1++ evidence and grade A recommendation).(4) The Drug and Therapeutics Bulletin recently systematically reviewed the value of this treatment and concluded: “The current British Guideline on the Management of Asthma, published jointly by the British Thoracic Society and the Scottish Intercollegiate Guideline Network suggests that a single intravenous dose of magnesium sulphate [sic] should be used for the treatment of patients with acute severe asthma. However, the available data are weak and conflicting and do not justify this unlicensed use of the drug.”(5)

Clinical guidelines constantly face challenges from dissenting authoritative reinterpretation of existing evidence and from new, relevant evidence that was unavailable at the time the recommendations were developed. In addition, however evidence based the process of development may be, a guideline may not easily be applied to a particular patient’s care (box 1). Clinical guidelines should therefore be understood to command only a provisional title to be believed. Nevertheless, the General Medical Council has announced that doctors should “normally follow guidelines,”(6) and a leading UK barrister in health law has concluded that the effects of guidelines and evidence based medicine combined are that many areas of medicine and surgery, which attract the attention of civil litigators, are or will be governed by clinical guidelines. Increasingly, it will be possible to plead just one particular form of negligence: failing to follow guideline X.(7)

Medical negligence
The Oxford English Dictionary defines negligence as “a want of attention to what ought to be done or looked after,” a failure to match up to required standards of performance (see box 2). Within the common law, a tension exists between descriptive tests of medical negligence, which gauge conduct under scrutiny against the standard of what is done in practice, and normative tests, which focus instead on what ought to be done. The former generally presume that customary professional practice embodies acceptable and legal standards, whereas the latter allow for standards to be determined by other criteria, such as those set forth in statements of good practice or evidence based guidelines.

In respect of standards of information disclosure to patients, UK courts have generally adopted a customary test approach, basing their decisions on what a responsible body of doctors would tell patients about a proposed treatment or procedure in identical or very similar circumstances. In the 1970s, case law in the United States developed a more patient oriented test that allowed courts to ignore what responsible doctors actually tell patients, and to ask instead what a reasonable patient would want to know in the circumstances.(11) Australian courts have gone further, ruling that doctors should disclose all material risks that a reasonable patient is likely to regard as important.(12) In this respect, common law courts have not simply made decisions that reflect professional practice; they have fashioned entirely new healthcare standards by formulating legal tests that are sensitive to patient values and concerns.(13)

Negligence is a normative legal doctrine (box 3). The US case of Helling v Carey (1974) (see box 4) and that reported by Merenstein (see box 5) show the courts trying to come to grips with whether customary and evidence based standards could be negligent. As far as medical treatment is concerned, courts clearly have the jurisdiction to set standards of clinical care (box 3), but they rarely exercise this power without reference to a test of customary practice.(14)



In the United Kingdom, the standard of care required successfully to defend a negligence claim derives from the case of Bolam v Friern Hospital Management Committee (1957): “The test is the standard of the ordinary skilled man exercising and professing to have that special skill.”(19) Expert testimony helps courts decide what is accepted and proper practice in specific situations, ensuring (in theory) that professionally generated standards relating to actual clinical practice are applied by the courts, rather than standards derived from elsewhere, such as from guidelines.(20)

The judge in Bolam recognised that there could be two or more schools of thought regarding proper medical treatment, so doctors can usually rebut a charge of negligence if they have acted in accordance with practice approved by a body of other responsible doctors.(19) In Cranley v Medical Board of Western Australia (1990) an Australian general practitioner stood accused of misconduct because he had prescribed injectable diazepam to heroin users, contrary to the then recommendations of the Australian methadone guidelines. The initial court’s finding of “infamous and improper conduct” was reversed by the Supreme Court of Western Australia, after it heard of a minority medical opinion that supported treatment of opiate users within a harm reduction framework as followed by Cranley.(21) In this case the court found that a practice outside nationally recognised guidelines was nevertheless acceptable and lawful.

The Bolam test takes account of evolving standards of care once collectively expressed in practice. It is a professionally led (although legally imposed) standard; it allows for genuine differences of professional opinion(22); and it is sufficiently broadly formulated to encompass practices based both on science (“knowledge that”) and on craft (“know how”) foundations. Unlike tests of negligence adopted in some other common law jurisdictions, such as Canada (where the test is “that degree of care and skill which could reasonably be expected of a normal prudent practitioner”),(23) Bolam is a “state of the art” descriptive test pegged to professionally defined practice, albeit a practice that since Bolitho v City & Hackney Health Authority (1997) must be capable of withstanding logical analysis if it is to be acceptable to the courts.(24)

The Bolam test has been criticised for adopting a sociological criterion that legitimises the force of custom; in an evidence linked era, the test is believed to demand too little by way of encouraging higher standards of care. Should the test for negligence be made more responsive to evidence, to avoid courts being influenced by out of date customary practices, by professional standards for which there is little supporting (or even strong contrary) evidence, or by expert witnesses whose views may be insufficiently tested in court?(25)(26)

Evidence based guidelines offer doctors and patients explicit examples of well justified and articulated standards of care for use in specific clinical circumstances. As such, they could remove the need for expert testimony as the courts would have direct access to relevant standards from guidelines(27) that, if relied on, would detach determination of legal standards of care from anchorage in customary medical practice.

Guidelines and the courts
Guidelines are introduced into courts by expert witnesses as evidence of accepted and customary standards of care, but cannot, as yet, be introduced as a substitute for expert testimony. In court they are treated as hearsay evidence: the mere fact that a guideline exists can neither establish its authority nor support the view that in the circumstances before a court compliance with the guideline would be reasonable and non-compliance negligent. Yet in the United States a study has shown that guidelines play a relevant or pivotal part in the proof of negligence in 6-7% of malpractice actions.(28)

A high proportion of guidelines fall short of meeting quality markers (see box 6), so it is important to prevent poor guidelines from influencing legal standards. However, this very possibility may eventuate because the courts do not generally call experts in guideline methodology to assist them in assessing the robustness and quality of clinical guidelines cited.(29)

If the presumption is that courts should consult clinical guidelines because they reflect customary standards of care, then the authority of newly developed guidelines that make recommendations departing from usual practice would be diminished,(31) as would guidelines motivated by cost cutting (see box 4). But if the presumption is that guidelines should be consulted by courts because they provide evidence of standards justified in relation to evidence rather than custom, this would radically strengthen the normative dynamic of the law in actions alleging medical negligence. It would also introduce a test of culpable fault much harder for defendants to meet than that represented by the Bolam test (even when modified by Bolitho(24)). The effect would be to propel medical compliance with—possibly slavish obedience to—clinical guidelines.

At a time when only a tiny proportion of guidelines has been shown in rigorous trials to lead to better outcomes, such mass conversion by clinicians may not be desirable. Translating guideline standards into legal standards would tend to deny a role for judgment in using guidelines, which could lead to increased legal scrutiny of guideline development procedures and their authorship processes.

Author or sponsor liability
Allegations of bias have been laid before the French fraud squad, alleging improper conduct by participants in the French guidelines programme.(32)(33) Bias is also a concern of the American Medical Association (AMA), which believes that “bad faith claims could be lodged against developers who stand to benefit from the content of a guideline and who design results to comport with desired cost containment goals.”(34)

The AMA has outlined scenarios that it believes could ground a claim against guideline developers. These include defects in “analysing or interpreting data, or translating data into a guideline, ignoring well-known and scientifically valid data, and utilising data that were known, or should have been known, to be insufficient or faulty.”(34) It advises guideline developers to “assume that their research methodology and resulting conclusions will subsequently be subject to legal review and to proceed with the assumption that they may be challenged in court.”(34) To date, no cases have arisen in either US or UK jurisdictions in which the courts have been asked to decide whether guideline authors were liable for incorrect or misleading statements.

However, in non-medical spheres, UK courts have decided similar questions where people have suffered economic loss by relying on written statements of advice.(35) The general position is that there can be no duty of care between the author of a document or book and its myriad potential readers, unless the authors could foresee that their written advice would be directly communicated to a reader, who would have little choice but to rely on it without independent enquiry. For doctors to be expected to follow guidelines without further inquiry, the guidance would require to be credited with an authority that completely overruled clinical judgment.(36) This seems to have been the view taken by a court in the case of Sutton v Population Family Planning Programme Ltd (1981), in which a nurse who failed to follow a written procedure for referring a patient complaining of a breast lump was found to be negligent on that account.(37)

The status of guidelines should be made clear to clinicians in a prefatory statement, such as that which appears in the NICE guidelines on Core Interventions in the Treatment and Management of Schizophrenia in Primary and Secondary Care: “This guidance represents the view of the Institute, which was arrived at after careful consideration of the evidence available. Health professionals are expected to take it fully into account when exercising their clinical judgment. The guidance does not, however, override the individual responsibility of health professionals to make decisions appropriate to the circumstances of the individual patient, in consultation with the patient and/or guardian or carer.”(38)

The expectation of guideline users is that they should behave as learned intermediaries, exercising customary clinical discretion and consulting other sources of relevant information.

In general, doctors are expected to use appropriate clinical judgment when deciding medical treatment, and this may be one reason why the courts continue to place the testimony of expert witnesses concerning what constitutes reasonable practice above the recommendations of prestigious works of reference and guidelines. Even where a guideline has been laid down as a legal standard, courts require sensible judgment be used in its appropriate application.(39)

In administrative law, the essence of discretion is “a readiness to deal with each case on its merits.”(40) The NHS Executive acknowledges that, when endorsed by prestigious professional bodies or even commended by the NHS Executive, “clinical guidelines can still only assist the practitioner; they cannot be used to mandate, authorise or outlaw treatment options. Regardless of the strength of the evidence, it will remain the responsibility of the practising clinicians to interpret their application … It would be wholly inappropriate for clinical guidelines to be used as a means of coercion of the individual clinician, by managers and senior professionals.”(41)

Rigid, uncritical adherence to guidelines is therefore not the formal, administrative, or managerial expectation of clinicians working in the NHS. In the United States, tensions surfacing between treatment protocols and doctors’ clinical judgment have led the courts to rule that clinicians may not claim as a defence to negligence that their clinical judgment has been corrupted by guidelines.(42)

Although treatment choices in discrete areas of medicine can be more or less explicitly specified in guidelines, this does not reduce clinical decision making to a process of decisional algebra, entirely governed by algorithms or protocols. Some clinical judgments go beyond explicit input information, adding considerations of feeling, attitude, and value to the output,(43) effects detectable in guideline development processes whose recommendations are not entirely insulated from the evaluative aspects of judgment.(44)

Sir Michael Rawlins, the chairman of NICE, accepts that “No guideline can cover 100 per cent, because people vary. It’s up to the doctor or other health professional to decide when the guideline is no longer applicable and what to do in its place.”(45) He believes that up to a fifth of clinical decisions taken in situations prima facie covered by guidelines may quite properly deviate from them. The evidence for this claim has not been made explicit, but in these situations, NICE,(45) the Department of Health,(46) and the British Medical Association(47) all concur in advising doctors who deviate from guidelines to record treatment decisions in medical records “in ways that show that they have considered the guidelines.”(47) Arguably at least as important is to set up a database of departures from clinical guidelines, to enable the reasons why clinicians depart from evidence based guidelines to be studied and appreciated (personal communication, Andrew Herxheimer, 2004).

NICE and guidelines
How, if at all, does the arrival of NICE alter the legal status of guidelines? NICE was set up to give guidance to the NHS as a whole, to government, and ultimately to patients in several areas of health care, including the creation of clinical guidelines.(48) According to the memorandum setting out the ground rules under which NICE operates: “All guidance must be fully reasoned and written in terms which makes clear that it is guidance. Guidance for clinicians does not override their professional responsibility to make the appropriate decision in the circumstances of the individual patient, in consultation with the patient or guardian/carer and in the light of any locally agreed policies. Similarly, guidance to NHS trusts and commissioners must make clear that it does not take away their discretion under administrative law to take account of individual circumstances.”(48)

NICE has also been charged with ensuring that its recommendations are transmitted to national service frameworks and related quality of care initiatives, such as PRODIGY guidelines, the National electronic Library for Health, protocols used by NHS Direct and NHS Walk-in Centres, and any material for patients produced by NHS Direct Online. NICE is therefore structurally and strategically positioned to be at the hub of a series of influential mechanisms designed to implement its guidance. How realistic, therefore, is the Department of Health’s simultaneously held view that NICE guidance should not be thought to undercut or override clinicians’ professional responsibility to make appropriate decisions in the circumstances of the individual patient? What model of the relation between guideline and doctor underlies NICE clinical guidelines?

NICE posits doctors as free agents, capable of taking advantage of authoritative guidance without entering into a relation of professional reliance on guidelines. The aim is to enhance “holistic care” and to produce “�developmental standards,’ standards that the NHS is expected to achieve over time.”(46) Yet, NICE guidance aims to be authoritative—to carry the authority of evidence and of reason—and its strategic position in the NHS reinforces that authority. Since authority relations are predicated on “some species of surrender of judgment on the part of those who accept, submit or subscribe to the authority,”(3) does NICE guidance bind clinicians to such an extent that it also pre-empts their judgment, whether or not they agree with the guidelines?

The normal reason for following advice is that it is likely to be sound. The Department of Health explains: “The Institute’s purpose is to help reduce uncertainty for health professionals and their patients. NICE guidance sits alongside the knowledge and skills of experienced health professionals. It is not the intention of NICE guidance to replace the clinician’s knowledge and skill, rather to support it.”(46)

The Department of Health refers to a medical defence society, which agrees that such guidance legally carries “great weight,” meaning that clinicians charged with negligence and who have complied with NICE guidelines “can count on this fact to help their defence, but it does not necessarily follow … that health professionals who deviate from NICE guidance are negligent. Whilst there is always likely to be a ‘responsible body’ of health professionals supporting the recommendations made in NICE guidance, there may be other health professionals who subscribe to a different view.”(46)

The legal determination of negligence depends on the collection and interpretation of evidence, as courts are tribunals of fact that are required to piece together what has happened in the past from testimony and records of differing completeness and reliability.(49)

Evidence in medicine refers to information derived from observation, reasoning or experiment linked analytically to conclusions and beliefs. The term “evidence based” does not refer to a new notion of evidence or even to a new conception of its importance—the key contribution of evidence based medicine lies in its ranking of the credibility to be accorded to evidence depending on factors such as the likelihood of bias influencing data collection and interpretation.

Evidence based guidelines are standardised specifications of care that apply to the general condition and not necessarily to the particular clinical situation at hand; they therefore require extrapolation to an individual patient’s circumstances. Guidelines are synthesised from many sources of information and may create a false sense of consensus, may mask or underplay controversy, and can rapidly become out of date as a result of new findings. Many guidelines face more or less well grounded degrees of dissent much of the time. Recognition of the role of clinical discretion in taking account of particular circumstances underpins the lack of an administrative or legal requirement that doctors should always follow authoritative guidelines.

Some degree of discretion lies at the heart of clinical judgment, whichalmost always has to take account of competing influences on decision making such as the patient’s choice, healthcare targets, costs, and incentives. But discretion requires to be exercised in accordance with the patient’s best interests and within professional bounds. This will often, but not always, entail acting in accord with authoritative guidelines.

Although negligence is a normative doctrine (see boxes 3-5), in respect of medical treatment, descriptive legal tests for deciding what constitutes substandard care predominate. In the United Kingdom, the Bolam test has not been superseded by one that compares a treatment offered with a standard fashioned without reference to a responsible body of medical practitioners. Nevertheless, guidelines are highly influential in the way that doctors practise and the manner in which they are to be held accountable.

The creation of NICE, with its dual role of developing authoritative guidelines and of disseminating them through official NHS channels, means that its guidelines are likely to be credited with a distinctive authority medically and therefore legally.(50)(51) The current situation has been encapsulated in this way: “Guidelines are no substitute for expert evidence about acceptable practice. Compliance with well recognised guidelines is likely to exculpate (exonerate). Deviation from well recognised guidelines may be Bolam defensible.”(7)

Yet Merenstein regrets that “a physician can be put on trial for following national guidelines, the best evidence, the current research, and [can] then be found negligent for not following outdated and unsupported ‘community’ practices.”(52) However, because of the logical gap between the generalities of guideline recommendations and the particularities of a patient’s case, a good rule of thumb is that “following evidence based guidelines may generally but not always assure good medical care, and diverging from guidelines does not always signal poor care.”(53)

Merenstein’s experience has attracted further research and commentary, based on study of the judge’s notes and interviews with three members of the jury of the case.(54) Although the clinic in which Merenstein worked had no written policy for conducting health checks in men over the age of 50, the particular patient concerned had had previous estimations of prostate specific antigen (PSA) undertaken at previous checkups in the same clinic. Both these considerations may have weighed with the Virginian jury, who found the clinic negligent for having operated a substandard system of health maintenance checks (perhaps because without a policy it could not sufficiently guard against PSA testing being entirely dependent on which doctor a patient happened to consult) and yet exonerated Merenstein.

As we have seen, it is not beyond the bounds of possibility that in very particular circumstances, adherence to evidence based guidance associated with harm to patients could be deemed inappropriate and even negligent by the courts, but such cases remain rare and have generally not set legal precedents.

Evidence based guidelines set normative standards such that departure from them may require some explanation, but they do not constitute a de facto legal standard of care. They take the finder of fact (judge in the United Kingdom, jury in the United States) to a very definite starting place—namely to justified, advocated medical standards—from which to make an assessment of questionable conduct, and this represents quite a departure for the process of adjudication hitherto adopted by the courts, which has relied almost exclusively on expert witnesses setting normative boundaries. Because bona fide guidelines carry a presumptive status that means clinicians should generally follow them and if not should take account of them, courts now have available to them the added information and wisdom that guidelines embody.

The bottom line so beloved of EBM readers is: guidelines do not actually set legal standards for clinical care but they do provide the courts with a benchmark by which to judge clinical conduct.

Acknowledgement: I thank Rory McDonagh, Richard Ashcroft, and Andrew Herxheimer for helpful discussion and commentary on an earlier draft of this paper.

Competing interest: BH is a member of the evidence based guideline development group of the National Collaborating Centre for Chronic Disease, which is developing clinical guidelines for Parkinson’s disease for NICE.

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