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Original Hierarchy of Strength of Evidence for Treatment Decisions (Guyatt et al 2002).1
| N-of-1 Randomized Trial |
|---|
| Systematic reviews of randomized trials |
| Single randomized trial |
| Systematic review of observational studies addressing patient-important outcomes |
| Single observational study addressing patient-important outcomes |
| Physiologic studies |
| Unsystematic clinical observations |
