Table 4.
Sensitivity, specificity, and accuracy of GH peaks to GH stimulation tests isolated and in association with IGF-1 SDS for the diagnosis of IGHD.
| CP | ITT (%) | ITT or IGF-1 <−2SD (%) | ITT or IGF-1 <−1SD (%) | CT (%) | CT or IGF-1 <−2SD (%) | CT or IGF-1 <−1SD (%) | ITT plus CT (%) | |
|---|---|---|---|---|---|---|---|---|
| <3 μg/L | Sens | 38.8 | 42.9 | 53.1 | 38.6 | 45.5 | 54.6 | 22.9 |
| Spec | 50 | 90.9 | 63.6 | 63.2 | 84.2 | 79 | 76.9 | |
| Accu | 42.3 | 57.8 | 56.3 | 46 | 57.1 | 61.9 | 37.5 | |
| <5 μg/L | Sens | 81.6 | 81.6 | 81.6 | 70.5 | 75 | 79.6 | 62.9 |
| Spec | 36.4 | 81.8 | 54.6 | 36.8 | 79 | 68.4 | 69.2 | |
| Accu | 67.6 | 81.7 | 73.2 | 60.3 | 76.2 | 76.2 | 64.6 | |
| <7 μg/L | Sens | 93.9 | 93.9 | 93.9 | 93.2 | 93.2 | 95.5 | 88.6 |
| Spec | 22.7 | 81.8 | 45.5 | 26.3 | 68.4 | 57.9 | 53.9 | |
| Accu | 71.8 | 90.1 | 78.9 | 73 | 85.7 | 84.1 | 79.2 | |
| <10 μg/L | Sens | 95.9 | 95.9 | 95.9 | 93.2 | 93.2 | 95.5 | 91.4 |
| Spec | 13.6 | 81.8 | 40.9 | 26.3 | 68.4 | 57.9 | 46.2 | |
| Accu | 70.4 | 91.6 | 78.9 | 73 | 85.7 | 84.1 | 79.2 |
CP, Cut-off point; GH, Growth Hormone; IGF-1 SDS, Insulin-like Growth Factor 1 Standard Deviations; IGF-1, Insulin-like Growth Factor 1; IGHD, Idiopathic Growth Hormone Deficiency; ITT, Insulin Tolerance Test; CT, Clonidine Test; Sens, sensitivity; Spec, specificity; Accu, accuracy.