The TSAb blood test correctly identifies 63% of people who will relapse after stopping Graves disease medication and correctly rules out relapse in 83% of those who won’t, making it a more reliable predictor than the TBII test, which misses many relapses and has lower accuracy.
Evidence from Studies
No evidence studies found yet.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
A meta-analysis of all studies using the Mc4 TSAb assay and second-generation TBII assay could determine pooled sensitivity, specificity, and diagnostic odds ratios to establish which test is more accurate across populations.
A systematic review and meta-analysis of all prospective studies comparing TSAb (Mc4 assay, cutoff ≥140% SRR) and TBII (B.R.A.H.M.S. or M22, cutoff ≥1.5 IU/L) at antithyroid drug withdrawal for predicting relapse, reporting sensitivity, specificity, and likelihood ratios with 95% CIs.
An RCT could test whether using TSAb instead of TBII for clinical decisions reduces relapse rates or unnecessary treatments.
A multicenter RCT of 400 adults with Graves disease in euthyroidism after antithyroid drugs, randomized to TSAb-guided management (RAI if TSAb ≥140%) vs. TBII-guided management (RAI if TBII ≥1.5 IU/L). Primary outcome: relapse-free survival at 24 months.
A prospective cohort study could validate the diagnostic accuracy of TSAb and TBII in a new population using the same outcome definition and assay methods.
A prospective cohort study of 300 adults with Graves disease achieving euthyroidism after antithyroid drugs, measuring both TSAb (Mc4) and TBII (B.R.A.H.M.S.) at withdrawal, then following them every 3 months for 24 months with blinded thyroid function testing to determine sensitivity and specificity.
A case-control study could compare TSAb and TBII levels at withdrawal between relapsed and non-relapsed patients to assess which test better discriminates between outcomes.
A case-control study of 100 patients with Graves disease who relapsed within 24 months of drug withdrawal and 100 matched controls who remained in remission, comparing TSAb and TBII levels at withdrawal using the same assays and cutoffs.
A cross-sectional study could estimate the distribution of TSAb and TBII levels at withdrawal but cannot determine diagnostic accuracy without outcome data.
A cross-sectional study measuring both TSAb and TBII levels at antithyroid drug withdrawal in 500 consecutive adults with Graves disease, reporting median levels and positivity rates.