Strength of study design
I. Randomized controlled clinical
trials (RCT)
II. Non-randomized controlled
clinical trials (NRCT)
III. Case series (CS)
IV. Best case series (BCS)
Strength of endpoint
A. Overall survival (OS)
B. Disease-specific survival
(DSS)
C. i. Carefully assessed quality
of life (Qol)
ii. Treatment-induced toxicity
D. Indirect surrogates
i. Disease-free survival
ii. Progression-free survival
iii. Tumor response rate
iv. Local and locoregional
control
http://www.cancer.gov/cancertopics/pdq/levels-evidence-cam/healthprofessional/Veldeman L. et al. Lancet Oncol. 2008 Apr;9(4):367-