Table 2.
Median and 97.5th percentiles of the TSH distribution for three population samples
| Study (Ref.) | n | TSH (μIU/ml)
|
|
|---|---|---|---|
| Median | 97.5th percentile | ||
| NHANES III | |||
| Entire cohort (5) | 17,353 | 1.49 | 5.8 |
| Disease free (5)a | 16,533 | 1.49 | 5.52 |
| Disease free risk free (2)b | 14,333 | 1.40 | 4.2 |
| Normal reference population (5)c | 13,344 | 1.39 | 4.12 |
| Kratzsch et al. (15) | |||
| All healthy blood donors | 870 | 1.31 | 3.63 |
| Healthy blood donors with normal thyroid glandd | 453 | 1.36 | 3.77 |
| HTDS | |||
| TSH by ELISA | |||
| Entire cohort | 1861 | 1.35 | 5.67 |
| NRG-1 | 1448 | 1.35 | 3.73 |
| NRG-2 | 1186 | 1.30 | 3.37 |
| NRG-3 | 766 | 1.32 | 3.37 |
| TSH by ICMA for NRG-3 | e | 1.69 | 4.1 |
a
Excludes those reporting thyroid disease, goiter, or taking thyroid medication.
b
Disease free group that also excludes those with antithyroid antibodies, those taking lithium, or those discovered biochemically to have overt hyperthyroidism or hypothyroidism.
c
Disease free risk free group that also excludes those who are pregnant, or are taking estrogen or androgen.
d
Excludes those with a personal or family history of thyroid disease, an abnormal thyroid ultrasound, or increased antibody.
e
Based on the regression equation relating the 50 ICMA values to ELISA values.