Practice guidelines for neurosurgery originally were developed as an academic tool for reducing the practice variation which existed across geographic regions and among institutions. Some neurosurgeons perceived practice guidelines as useful tools for establishing uniform care in rapidly evolving specialty areas, such as neurotrauma and neurocritical care, in which expensive technology and invasive monitoring procedures are used. Others were wary of “cookbook medicine” and feared compromise of physician autonomy.
Practice guidelines arose from evidence-based medicine, the need for which was formalized by the Institute of Medicine in two influential and widely publicized reports, To Err Is Human in 1999, and Crossing the Quality Chasm in 2001. In the latter report, four of the thirteen recommendations-specifically recommendations 4, 7, 8, and 10-focused on amassing evidence of best-practice treatments and procedures and assessing their efficacy. In March of this year, the Medicare Payment Advisory Commission told Congress that Medicare reimbursement should be linked to quality measures, hastening the need for development of such quality measures should the recommendation be accepted. It would not be surprising if in the next few years neurosurgeons are required to explain care that deviates from accepted clinical guidelines in order to receive full reimbursement.
For many reasons, the onus is on neurosurgery to develop clinical practice guidelines as anchors for best practice benchmarking. The healthcare system hasn’t the time, the expertise, or the funds to produce specialty-specific clinical practice parameter guidelines on its own. Payers are likely to adopt and sanction guidelines generated by professional organizations whenever they are available, and the guidelines endorsed likely will be disease centered rather than procedure or specialty focused. Without participation of neurosurgeons in the development of pertinent guidelines, neurosurgeons might be held to clinical practice parameters produced by other societies that have overlapping clinical interests.
Establishing Guidelines for Guidelines
In general, there are three main methods of guidelines development: informal consensus, formal consensus, and evidence-linked development. Only the latter meets the standards for evidence-based medicine. Indeed, the IOM hopes to eventually restrict the use of the term “guideline” to systematically developed advisory statements created according to validated methodology. Without strict adherence to systematic and validated methodology, the guidelines produced may represent pooled ignorance rather than distilled wisdom.
Construction of guidelines involves, first, a systematic means of identifying evidence and ranking the relative strengths, or quality of each study as evidence, and second, achieving panel agreement on a strength of recommendation linked to the analysis of the strength of evidence for each intervention in question. Both steps are critically important and have their own drawbacks and limitations.
The ultimate validity of any guideline is related to three key factors: 1) the composition of the guideline panel and its process; 2) the identification and synthesis of the evidence, and 3) method of guideline construction applied.
The panel composition is crucial, both for ultimate acceptance of the guidelines by practicing physicians and for its critical influence on the recommendation step of guideline construction. Panels that over-represent certain disciplines or exclude other key disciplines or dissenting voices may be seen as less credible. Successful introduction of a guideline requires that all key disciplines contribute to its development to ensure ownership and support.
Panelists’ recommendations can differ even when analyzing the same data. In general, studies of guidelines development have suggested that U.S. experts tend to be more action oriented than those from the United Kingdom; surgeons tend to be more certain about surgery than nonsurgeons; and generalists tend to be more conservative than specialists. Guidelines produced by advocacy groups and subspecialty societies tend to be most problematic and suspect due to problems with unbalanced panel representation as well as methodological concerns. Recommendations made by specialists sometimes are more influenced by the specialty to which they belong rather than by the scientific evidence. Further, a 1999 study by Shaneyfelt and colleagues reviewed the methodological quality of guidelines produced by scientific societies and found that even basic methodological principles often are overlooked.
Ultimately, the quality and effectiveness of guidelines depends at least as much on the quality of the consensus development involved in deciding the strength of recommendation (the second step of guidelines construction), as on the quality of the evidence base. Strength of recommendations is a complex topic that implies value judgments on top of methodological assessments of evidence. It should incorporate subjective considerations such as patient- or setting-specific applicability, and also balance risks, benefits and costs.
Given the new significance of evidence-based medicine in the current healthcare climate, further exploration of how to develop reasonable and valid neurosurgical clinical guidelines that cover as many areas of neurosurgery practice as possible is both important and desirable.
Mark E. Linskey, MD, is associate professor and chair of the Department of Neurological Surgery at UCI Medical Center, Orange, Calif.
For More Information
Institute of Medicine, www.iom.edu
Shaneyfelt TM, Mayo-Smith MF, Rothwangl J. “Are Guidelines Following Guidelines?” The Methodological Quality of Clinical Practice Guidelines in the Peer-Reviewed Medical Literature.” Journal of the American Medical Association. 1999; 281(20):1950-1951.