Methodology: Guideline Development Rationale and Process

In order to create an evidence-based document relevant to the field treatment of brain injury, the literature was searched for each topic for publications on brain injury that pertained to the prehospital or austere environment. From the comprehensive literature searches, articles were selected which were relevant to the field management of traumatic brain injury (TBI) and utilized human data. Articles with outcomes related to morbidity and mortality were preferred. In establishing a literature base for recommendations, we generally only include publications that involve human subjects. However, in these Guidelines, we have included some publications that involve training with mannequins given that such training is an accepted practice in assessing competency for EMT certification. Additional studies were, in general, referenced only as a part of background discussion. The prehospital literature was heavily utilized; military literature was used where it was available.

Each chapter follows the same format:

1. Conclusions or Recommendations (for Treatment chapters only)
   1. Standards
   2. Guidelines
   3. Options
2. Overview
3. Search Process
4. Scientific Foundation
5. Summary
6. Key Areas for Future Investigation
7. Evidence Table
8. References

Section I describes the conclusions the authors formulated from the literature. For the chapters on assessment, which included prognosis studies, the authors summarized the evidence rather than made recommendations. Thus, their findings are listed as "Conclusions" for any diagnostic or prognostic assessment and as "Recommendations" where the end result is a specific treatment or set of treatment options. Section VII in each chapter provides a brief analysis of the literature that supports the conclusions or recommendations, whereas Section VIII references a more extensive list of studies.

The Guidelines follow the recommendations of the Institute of Medicine (IOM) Committee to Advise the Public Health Service on Clinical Practice Guidelines1 outlined below:

1. There should be a link between the available evidence and the recommendations.
2. Empirical evidence should take precedence over expert judgment in the development of guidelines.
3. The available scientific literature should be searched using appropriate and comprehensive search terminology.
4. A thorough review of the scientific literature should precede guideline development.
5. The evidence should be evaluated and weighted, depending on the scientific validity of the methodology used to generate the evidence.
6. The strength of the evidence should be reflected in the strength of the recommendations, reflecting scientific certainty (or lack thereof).
7. Expert judgment should be used to evaluate the quality of the literature and to formulate guidelines when the evidence is weak or nonexistent.
8. Guideline development should be a multidisciplinary process, involving key groups affected by the recommendations.

The American Medical Association (AMA) and many specialty societies, including the American Association of Neurological Surgeons (AANS) and the American Academy of Neurology (AAN), have further formalized this process by designating specific relationships between the strength of evidence and the strength of recommendations.2-4 Evidence is indexed into several classes.

Class I evidence is derived from the strongest studies of therapeutic interventions (randomized controlled trials) in humans. Used to support treatment recommendations of the highest order, they are called practice standards.

Class II evidence consists of comparative studies with less strength (nonrandomized cohort studies, randomized controlled trials with significant design flaws, and case-control studies) that are used to support recommendations called guidelines.

Class III evidence consists of other sources of information, including case series and anecdotal or descriptive studies that support practice options.

Standards, guidelines, and options reflect a high, moderate, or unclear clinical certainty, respectively, as indicated by the scientific evidence available. The overall term for all of the recommendations is practice parameters, or more commonly and what we called here, practice guidelines.

In partnership with the Evidence-based Practice Center (EPC) of Oregon Health & Science University (OHSU), a rigorous protocol for classification of evidence was adopted by the Brain Trauma Foundation (BTF) for all of its guidelines endeavors. Criteria for classification of evidence based on study design and quality are in Table 1.

The authors of these guidelines, entitled Guidelines for the Field Management of Combat-Related Head Trauma, represented a multidisciplinary group consisting of neurosurgeons, trauma surgeons, neurointensivists, and paramedics from both the civilian and the military sectors. They were selected for their expertise in TBI, combat medicine, or military medical education. All the military authors had recent combat experience. Each author independently conducted a MEDLINE or comparable search, reviewed and evaluated the literature for their assigned topics, then cooperated in formulating the Guidelines during several work sessions aimed at completing understandable and applicable recommendations based on the best evidence available. The template for these Guidelines was the first edition of the Guidelines for Prehospital Management of Traumatic Brain Injury developed by BTF in 1999-2000.

The Guidelines for the Field Management of Combat-Related Head Trauma covers three main areas: assessment, treatment, and triage and transport decisions. A consensus assessment and treatment algorithm is included to provide an overview of all these aspects of management. At several points during the development process, a review team comprised of representatives of the armed services medical "school houses," military neurosurgery and trauma surgery, and military medic instruction evaluated the document, and their comments were delivered to the authors. Several draft documents were produced and evaluated before this document was finalized and published.

The Brain Trauma Foundation of New York City managed the guidelines project under a grant from the Defense and Veterans Brain Injury Center (DVBIC) through the Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. DVBIC is a collaboration between the Department of Defense and the Department of Veterans Affairs. Its mission is to serve active duty military, their dependents, and veterans with TBI through state-of-the-art medical care, innovative clinical research initiatives, and educational programs. The Brain Trauma Foundation, founded in 1986, is a not-for-profit organization dedicated to improving the outcome of traumatic brain injured patients. It achieves its mission through evidence-based guidelines development, the education and training of medical personnel, quality improvement programs, and clinical research.

In 1995, BTF brought together a team of neurosurgeons from around the country to develop the first evidence-based guidelines for neurotrauma care. The Guidelines for the Management of Severe Traumatic Brain Injury was developed according to procedures set forth by the American Medical Association. The Guidelines cover specific treatments and the areas of care specifically related to the acute, intensive care phase of injury. Today, these Guidelines are approved by the American Association of Neurological Surgeons and endorsed by the Congress of Neurological Surgeons, the World Health Organization Neurotrauma Committee, and the New York State Department of Health, among others. In addition, the Guidelines appear in the American College of Surgeons handbook Resources for Optimal Care of the Injured Patient.

BTF has also developed Guidelines for the Surgical Management of Traumatic Brain Injury, addressing key topics in the acute neurosurgical management of TBI related to indications, technique and timing of operative procedures. The Guidelines are revised and updated approximately every five years. BTF has promoted the Guidelines nationally and internationally through lectures, presentations, the hands-on training of medical professionals, and distance learning.

It is understood that military operations take place in a wide range of physiological and logistical environments. The ability of the combatant to survive injury is heavily dependent on the circumstances of that injury. The goal of these Guidelines is to provide dispassionate analysis of the known benefits and risks of therapies available to the brain injured patient in the field. In this way, these Guidelines strive to be a resource and a tool for the combat medic, physician, commanding officer, and logistician who must then make the tough "on the ground" therapeutic, tactical, and logistical decisions that will ultimately result in optimum care for the injured combatant.