thyroid disease diagnostic algorithm
Last edited 04/2021 and last reviewed 04/2022
Where TSH and free T3 or T4 are measured as the first-line thyroid investigation there are six patterns of abnormality:
- TSH may be high or low
- free T3 or free T4 may be low, normal or high
Reference:
- Dayan CM. Interpretation of thyroid function tests. Lancet 2001;357:619-24.
low TSH, raised free thyroid hormones
low TSH, normal free thyroid hormones
low or normal TSH, low free thyroid hormones
raised TSH, low free thyroid hormones