A. For Diabetes, as per international guidelines, Fasting Blood Sugar greater than or equal to 126, Post Prandial Sugar greater than or equal to 200 B. For Hypothyroidism, as per international guidelines first test is TSH only. If TSH is elevated then we go for free T4 ( not T4 ), which is low in primary Hypothyroidism. But if TSH is high and free T4 is high, then it's subclinical Hypothyroidism. If TSH is normal, but patients has symptoms of Hypothyroidism then we repeat TSH and free T4 to get diagnosis of Central Hypothyroidism. International experts define an elevated serum TSH as a TSH concentration above the upper limit of the normal TSH reference range, which is typically 4 to 5 mU/L in most laboratories. Presently there is considerable controversy over the appropriate upper limit of normal for serum TSH. Some experts have suggested that the true upper limit is only 2.5 or 3 mU/L in healthy individuals without thyroid disease, while others argue that the serum TSH distribution shifts towards higher values with age, independent of the presence of antithyroid antibodies . In this case, the upper limit of normal could be as high as 6 to 8 mU/L in healthy octogenarians.