High: Image clinbone2fu1.jpgThere are consistent results from good-quality studies. Further research is very unlikely to change the conclusions.
Moderate: Image clinbone2fu2.jpgFindings are supported, but further research could change the conclusions.
Low: Image clinbone2fu3.jpgThere are very few studies, or existing studies are flawed.
Insufficient: Image clinbone2fu4.jpgResearch is either unavailable or does not permit estimation of a treatment effect.

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