Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
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connected to the .gov website. Share sensitive
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Grading of recommendations depending on their level of evidence
| Grade of recommendation | Criteria |
|---|---|
| A | If level 1 evidence was found (not the case in this study). |
| B | If level 2 evidence was found. |
| C | If level 3 evidence was found (mainly non-analytical studies such as case reports and case series). |
| D | If level 4 evidence was found (mainly expert opinion). |
