Note from the National Guideline Clearinghouse (NGC): The guideline is based on a 2-part systematic review prepared for the American College of Physicians (see "Companion Documents" field).
Preoperative Pulmonary Risk Stratification for Noncardiothoracic Surgery
The U.S. Preventive Services Task Force (USPSTF) criteria were used for assigning hierarchy of research design, grading a study's internal validity, and assigning summary strength of recommendation for each risk factor and laboratory test as follows.
A = good evidence to support the particular risk factor or laboratory predictor
B = at least fair evidence to support the particular risk factor or laboratory predictor
C = at least fair evidence to suggest that the particular factor is not a risk factor or that the laboratory test does not predict risk
D = good evidence to suggest that the particular factor is not a risk factor or that the laboratory test does not predict risk
I = insufficient evidence to determine whether the factor increases risk or whether the laboratory test predicts risk, and evidence is lacking, is of poor quality, or is conflicting
Strategies to Reduce Postoperative Pulmonary Complications after Noncardiothoracic Surgery
The Quality of Reporting of Meta-analyses (QUOROM) statement for reporting meta-analyses and the U.S. Preventive Services Task Force criteria for hierarchy of research design were used to assess internal validity and study quality (good, fair, or poor) and to make conclusions about strength of evidence as follows:
A = good evidence that the strategy reduces postoperative pulmonary complications and benefit outweighs harm
B = at least fair evidence that the strategy reduces postoperative pulmonary complications and benefit outweighs harm
C = at least fair evidence that the strategy may reduce postoperative pulmonary complications, but the balance between benefit and harm is too close to justify a general recommendation
D = at least fair evidence that the strategy does not reduce postoperative pulmonary complications or harm outweighs benefit
I = evidence of effectiveness of the strategy to reduce postoperative pulmonary complications is conflicting, of poor quality, lacking, or insufficient or the balance between benefit and harm cannot be determined.