From: Prosthetic joint infection development of an evidence-based diagnostic algorithm
LoE | |
 I | Prospective randomized controlled trials (ORCTs) |
 II | Clinical studies in which the data was collected prospectively, and retrospective analyses which were based on clearly reliable data Types of studies so classified: observational studies, cohort studies, prevalence studies and case control studies |
 III | Studies based on retrospectively collected data. Evidence used in this class indicate clinical series, database or registry review, large series of case reviews and expert opinion |
CoR | |
 I | The recommendation is convincingly justifiable based on the available scientific information alone. This recommendation is usually based on Class I data; however, strong Class II evidence may form the basis for a level I recommendation, especially if the issue does not lead itself to testing in a randomized trial. |
 II | The recommendation is reasonably justifiable by available scientific evidence and strongly supported by expert opinion This recommendation is usually supported by Class II data or a preponderance of Class II evidence |
 III | The recommendation is supported by available data but adequate scientific evidence is lacking This recommendation is generally supported by Class III data. This type of recommendation is useful for educational purposes and in guiding future clinical research |