Another type of review worth mentioning is the clinical guideline. A group of experts on a topic review all the literature and make recommendations on how to proceed with a given problem. Clinical studies are graded based on the strength of the evidence (usually by a predefined scoring system), typically Class I, II or III. Studies with “fatal flaws” are given a Class X designation. If there is no clinical trial, they fill in the gaps with their consensus, expert opinions.
- Level A recommendations. Generally accepted principles for patient management that reflect a high degree of clinical certainty (ie, based on strength of evidence Class I or overwhelming evidence from strength of evidence Class II studies that directly address all of the issues).
- Level B recommendations. Recommendations for patient management that may identify a particular strategy or range of management strategies that reflect moderate clinical certainty (ie, based on strength of evidence Class II studies that directly address the issue, decision analysis that directly addresses the issue, or strong consensus of strength of evidence Class III studies).
- Level C recommendations. Other strategies for patient management that are based on preliminary, inconclusive, or conflicting evidence, or in the absence of any published literature, based on panel consensus.
In Emergency Medicine, these are often held up to be the “standard of practice” and are used to defend practicing in a particular way.
patwari 