Table 3 Minimum occasions required to obtain a reliable estimate, intraclass correlation coefficients, and percent of true variance accounted for by single measurements
Analyte | Occasions (samples) | Measurement Occasions Required | ICC(2,1) (95% CI) | % of True Variance Accounted for by a Single Occasion (Range) | |
|---|---|---|---|---|---|
| Â | Â | To Account for 81% of True Variance | To be Within 20% of True Mean | Â | Â |
| Â | Â | Relative Method (95% CI) | Absolute Method | Â | Â |
Estradiol | 5 (100) | 8.26 (4.53–13.88) | 0.34 | 0.33 (0.18-0.51) | 37 (18-74) |
Free Estradiol | 5 (85) | 5.32 (2.92-8.94) | 2.00 | 0.41 (0.26-0.59) | 48 (29-72) |
Estrone* | 3 (60) | 11.43 (6.26-19.20) | 0.37 | 0.51 (0.30-0.69) | 50 (14-56) |
Estrone-sulfate | 5 (90) | 1.42 (0.78-2.38) | 2.03 | 0.71 (0.58-0.82) | 74 (53-77) |
Progesterone | 5 (100) | 5.15 (2.82-8.65) | 8.90 | 0.40 (0.25-0.58) | 40 (27-50) |
SHBG | 5 (85) | 0.48 (0.26-0.80) | 1.78 | 0.88 (0.81-0.93) | 92 (84-96) |
FSH | 5 (85) | 5.11 (2.80-8.59) | 2.63 | 0.40 (0.25-0.58) | 37 (22-66) |
E1-G | 5 (100) | 3.88 (2.13-6.52) | 0.92 | 0.47 (0.32-0.64) | 45 (29-55) |
LH | 5 (95) | 8.38 (4.59-14.07) | 8.08 | 0.30 (0.15-0.48) | 29 (17-62) |
PDG | 5 (100) | 5.17 (2.84-8.69) | 10.27 | 0.40 (0.25-0.58) | 32 (15-56) |
2-OHE1 | 5 (100) | 4.21 (2.31-7.07) | 1.57 | 0.46 (0.30-0.63) | 16 (4-40) |
16α-OHE1 | 5 (100) | 2.71 (1.48-4.55) | 2.44 | 0.56 (0.41-0.71) | 46 (14-79) |