Thyrotoxicosis
Low TSH
High T4
Primary Hypothyroidism
High TSH
Low T4
Secondary Hypothyroidism
Low TSH
Low T4
Sick Euthyroid
Low/Normal TSH
Low T4
Low T3
Subclinical Hypothyroidisim
OR
Poor compliance with thyroxine
High TSH
Normal T4
Steroid Therapy
OR
Subclinical Hyperthyroidism
Low TSH
Normal T4