Author Group

One of the most useful tools for learning about evidence-based medicine, guidelines, and the application of guidelines to the real world is a small text by David Sackett and the McMaster University group called Evidence Based Medicine.¹ We refer to this text several times in this chapter when discussing how to rate evidence and how to apply evidence to clinical situations. In the chapter devoted to a discussion of the creation of clinical practice guidelines, Dr. Sackett offers the reader the following advice:

Despite this warning, it is absolutely critical that physicians with clinical expertise participate in the formation of clinical practice guidelines. Although epidemiologic support is necessary for the analysis of study design, clinical data cannot be accurately interpreted and the translation of data to recommendation cannot be made without an understanding of the clinical significance of the data. This understanding does not come from textbooks. A more reasonable interpretation of Sackett’s statement is that it is not efficient or desirable to have individual groups spend the resources to develop practice guidelines at a local level. It makes more sense to have guidelines produced at a national level and leave the interpretation of those guidelines to the local experts. A series of review articles published in the Journal of the American Medical Association by the same author group offers detailed explanations of many of the concepts to be discussed in this chapter. The level of detail is inappropriate for this particular review, but the reader is encouraged to use these as references for further inquiry.^2–20

High-quality guidelines ideally have an author group that consists of a multidisciplinary panel of recognized experts in the disease process studied. Depending on the disorder studied, multidisciplinary may mean two related specialties (e.g., orthopaedics and neurosurgery for cervical spine trauma—no other specialties regularly deal with this issue) or perhaps members drawn from five or six disparate specialties (e.g., the American College of Radiology imaging appropriateness criteria, in which multiple specialties treat common clinical scenarios such as low back pain). Epidemiologic support is also crucial, and having an epidemiologist on the author panel is an ideal solution. All panel members should have some understanding of basic statistical methods and access to a statistician.

Conflict of interest is an important issue in the formation of a guidelines author group. Disclosure of such conflicts is the first step in managing conflicts, and the organizing body, be it a medical society, university work group, or insurance carrier, must decide how to manage or resolve the conflict. In some situations, compromises are necessary in order to garner sufficient topical expertise. In most situations, however, author groups can be constructed and organized to mitigate against the possibility of industry-related conflicts. It is our opinion that industry-sponsored “study groups” are an inappropriate source for clinical practice guidelines because the membership of and strategic direction of these panels may be easily influenced by the sponsoring body. Similarly, technology assessments produced by centers that are funded largely by third-party payers cannot be considered practice guidelines since they are paid for by entities primarily desiring to limit economic exposure as opposed to evaluating clinical efficacy. Furthermore, these panels notoriously lack relevant physician input and tend to place a higher value on study design and author interpretation of data than common sense and clinical fact. (e.g., go to www.ecri.org and review their assessment of “decompressive procedures for lumbosacral pain.” You will note that the author group contained only one physician, an Emergency Care Research Institute [ECRI] employee who practices internal medicine. No spine surgeon, physical therapist, rehabilitation physician, or other specialist input was solicited, and the topic is clearly ridiculous to anyone who regularly cares for these patients—decompression is not done as a treatment for low back pain, it is done for radiculopathy or stenosis.)

Those in the field of organized spine surgery, including the American Association of Neurological Surgeons and Congress of Neurological Surgeons Joint Section on Disorders of the Spine (Spine Section) and the North American Spine Society (NASS), have been active in guidelines development. The first significant product produced using modern evidence-based review techniques was the set of clinical practice guidelines dealing with cervical spine and spinal cord injury.²¹ The author group was recruited by Mark Hadley and consisted exclusively of neurosurgeons, both because of the funding agency (the spine section) and because of relative inexperience in guidelines formation. The group included general neurosurgeons, pediatric neurosurgeons, and neurosurgical spine specialists. Beverly Walters, a neurosurgeon who had trained in clinical epidemiology at McMaster University served as the epidemiologist. Each of the authors was employed at an academic center and had the support of local expertise in library science and statistics if necessary. The authors were tutored in evidence-based medicine techniques during 4-week-long sessions in order to solidify their ability to interpret the medical literature.

These guidelines were unique in the spine world and were qualitatively different from the various consensus-based guidelines that had been published previously (e.g., the NASS Low Back Pain Treatment Guidelines published in 1999). Because they applied to a relatively small patient population and because they were originally published as a supplement to Neurosurgery, a journal with virtually no penetrance into emergency medicine or orthopaedics, they did not receive immediate notoriety. With the exception of chapters dealing with the administration of steroids and the safety of traction reduction without MRI, very few recommendations were considered controversial.²¹

The AANS/CNS spine section was then charged with organizing a set of guidelines dealing with the topic of lumbar fusion. The section actively sought input from orthopaedic surgeons and physical medicine specialists in addition to neurosurgeons. Beverly Walters agreed to continue on in an advisory capacity, and several members of the cervical spine injury group, including Mark Hadley, were recruited to lend their expertise to the project. Because of the novelty of the process and the time commitment (a month away from home in addition to the time spent working on the project), it was difficult to recruit non-neurosurgeons. After being turned down four times by well known orthopaedic surgeons, the chairman of the NASS clinical care council, Bill Watters, volunteered himself and helped recruit Jeff Wang from UCLA to be the orthopaedic representatives on the panel. We were unable to recruit a physical medicine and rehabilitation physician to the panel, despite overtures to both local and national contacts.

Since the publication of the lumbar fusion guidelines, the visibility of guidelines formation has increased substantially. The economic effect of the recommendations, the timeliness of the publication in relationship to a political and popular examination of lumbar fusion, a more easily searchable publication format, and inclusion in the NGC substantially improved penetrance of these guidelines compared with that for the cervical spine injury guidelines. Vocal objections to the formation of clinical practice guidelines by “grass roots” neurosurgeons (via the Council of State Neurosurgical Societies) and others focused attention on the process. The use of guidelines to support continued patient access to spinal surgeons in Washington State and in several national insurance plans by a coalition of national organizations, including the AANS, CNS, NASS, American Association of Orthopedic Surgeons (AAOS), and Scoliosis Research Society (SRS), further highlighted the importance of such activities.

Subsequent guidelines efforts sponsored by the spine section or NASS have uniformly included broad representation of relevant clinical specialties. Both organizations require intensive training of author panel members. The AANS/CNS guidelines committee continues to rely on a didactic series of lectures developed by Beverly Walters and moderated by the chairs of the guidelines committee (currently Mark Linskey and Tim Ryken). The NASS has employed an online training module combined with on-the-job training. Bill Watters and Chris Bono have effectively used the NASS infrastructure to develop a primarily web-based mechanism for guidelines formation. Both organizations have now developed a cadre of well-trained clinician authors, both support multidisciplinary guidelines formation, and both support consultation with professional epidemiologists as needed.

Question Formation

Once an author group is formed, a set of questions is developed. The questions asked are a very important determinant of the utility of the ultimate guideline document. Questions need to be both relevant and answerable. A question such as, “What is the best treatment for low back pain?” is unanswerable. Patients with low back pain are a heterogeneous population. Back pain may be caused by muscular strain, traumatic injury, degeneration of the intervertebral disc, or spinal tumors. It may be a symptom of renal calculi, dissecting aortic aneurysm, or a somatization disorder. There is, therefore, no one best treatment for back pain, and attempting to answer such a question is a frustrating and fruitless endeavor. A better question would be “In a patient with recalcitrant low back pain and neurogenic claudication due to spondylolisthesis and stenosis, does surgical intervention improve outcomes compared with the natural history of the disease?” Here, the patient population is well defined and the treatment modalities are well described, allowing a meaningful review of the medical literature. During the literature search, it may become apparent that multiple surgical interventions are employed, resulting in the parsing of the question into subcomponents related to individual surgical techniques.

Literature Search

The availability of computerized search engines has greatly simplified the ability to identify potentially useful references. Most guidelines groups use two different search engines and databases to ensure a thorough search. Familiarity with mesh headings or consultation with a librarian is very useful in creating an effective search that will not be overly inclusive. Unfortunately, the era of electronic publishing has greatly increased the number of potentially useful references (when just the title and abstract are available for initial screening), and it is not uncommon to obtain several hundred or even several thousand references that require individual review. Several strategies can be used to speed this process. First of all, if sufficient high-quality evidence, such as several concordant randomized trials, exists, lower-quality evidence may be ignored except as background information. For example, about 7 billion papers deal with the use of microdiscectomy for lumbar radiculopathy (OK, an exaggeration). Of these papers, 99.9% are case reports, small case series, technical notes, or historic anecdotes. There are a few large cohort studies with admittedly fatal flaws. Fortunately, several attempted randomized studies have been published within the last few years^22,23 that provide higher-quality evidence than all of the other papers. Instead of spending months describing each case series, we can focus our review on a detailed analysis of the higher-quality papers and simply summarize the findings of the various case series. If the primary references are flawed, however, then we must incorporate the lower-quality evidence into the analysis.