PLoS Medicineから
The GRADE System for Rating Clinical Guidelines
ぱっと読んだだけですが..
GRADEってGrades of Recommendation Assessment, Development and Evaluationの略です。
（
Atkins D, Best D, Briss PA, Eccles M, Falck-Ytter Y, et al. (2004) Grading quality of evidence and strength of recommendations. BMJ 328: 1490.
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