Determination of sample size
DIFFERENTIATED THYROID CANCER, SECONDARY, REMISSION
Non-inferiority will be demonstrated if the rate of patients in complete remission at 1 year after randomization does not differ by more than ΔL=−5%. Setting the significance level at 0.025 (one-sided) and a power of 80% requires a sample size of 598 patients without Tg antibodies (299 per group) (Nquery software).In this network’s previous study, 94% of the low-risk patients (including 12% T2N0) were in complete biological remission at 1 year after randomization [If 5% secondary exclusion (final histopathology not differentiated thyroid cancer): 628 patients are required for randomization.