Strength of Evidence Scale

High: Image clinadhdfu1.jpgThere are consistent results from good-quality studies. Further research is very unlikely to change the conclusions.
Moderate: Image clinadhdfu2.jpgFindings are supported, but further research could change the conclusions.
Low: Image clinadhdfu3.jpgThere are very few studies, or existing studies are flawed.
Insufficient: Image clinadhdfu4.jpgResearch is either unavailable or does not permit estimation of a treatment effect.

From: Attention Deficit Hyperactivity Disorder in Children and Adolescents

Cover of Comparative Effectiveness Review Summary Guides for Clinicians
Comparative Effectiveness Review Summary Guides for Clinicians [Internet].

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