NCI strength of study endpoints (A–D) |
NCI strength of study design (1–3) |
A = highest quality study |
1 = strong |
A Total mortality (or overall survival from a defined time) |
1 Randomized controlled trial
|
(i) Population-based, consecutive series |
(ii) Consecutive cases (not population-based) |
B Cause-specific mortality (or cause-specific mortality from a defined time) |
2 Non-randomized controlled trials
|
B = high quality study |
2 = weak
|
C Carefully assessed quality of life
|
3 Case series
|
C = low quality study |
|
(i) Population-based, consecutive series |
(ii) Consecutive cases, (not population-based) |
(iii) Non-consecutive cases |
D Indirect surrogates
|
|
D = lowest quality study |
|
(i) Event-free survival |
(ii) Disease-free survival |
(iii) Progression-free survival |
(iv) Tumour response rate |