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. Author manuscript; available in PMC: 2015 Jan 27.
Published in final edited form as: J Biopharm Stat. 2014;24(3):608–633. doi: 10.1080/10543406.2014.888437

Table III.

Relative bias, standard deviation and root mean squared error (RMSE) for the c2 estimates

Scenario True c2 Relative Bias Standard Deviation RMSE
n=m=k=20 n=m=k=40 n=m=k=80 n=50, m=35,
k=25		 n=m=k=20 n=m=k=40 n=m=k=80 n=50, m=35,
k=25		 n=m=k=20 n=m=k=40 n=m=k=80 n=50, m=35,
k=25
1 Youden: 1.500 0.0138 −0.0021 −0.0006 0.0080 0.3782 0.3103 0.2399 0.3502 0.3788 0.3104 0.2400 0.3504
CP: 1.711 0.0105 0.0072 0.0065 0.0099 0.2320 0.1713 0.1292 0.1870 0.2327 0.1718 0.1297 0.1878
Volume: 1.693 0.0094 0.0072 0.0070 0.0100 0.2534 0.1882 0.1440 0.2018 0.2539 0.1886 0.1445 0.2025
2 Youden: 0.750 0.2409 0.2345 0.1527 0.3035 0.6461 0.5193 0.4136 0.5797 0.6709 0.5482 0.4292 0.6228
CP: 1.035 0.0138 0.0191 0.0212 0.0266 0.3215 0.2211 0.1702 0.2631 0.3218 0.2220 0.1716 0.2645
Volume: 1.047 0.0083 0.0160 0.0182 0.0152 0.2783 0.2072 0.1575 0.2408 0.2785 0.2079 0.1587 0.2413
3 Youden: 1.373 0.0386 0.0318 0.0289 0.0531 0.4334 0.3086 0.2377 0.3562 0.4367 0.3117 0.2410 0.3636
CP: 1.171 0.0272 0.0241 0.0192 0.0310 0.3032 0.2076 0.1582 0.2426 0.3048 0.2096 0.1598 0.2453
Volume: 1.171 0.0137 0.0225 0.0164 0.0221 0.2750 0.1983 0.1507 0.2320 0.2755 0.2000 0.1519 0.2335
4 Youden: 1.899 −0.0149 −0.0062 0.0019 −0.0012 0.3787 0.2817 0.2109 0.3180 0.3798 0.2819 0.2110 0.3180
CP: 2.060 0.0089 0.0084 0.0086 0.0120 0.2275 0.1698 0.1219 0.1896 0.2283 0.1707 0.1232 0.1911
Volume: 2.041 0.0096 0.0082 0.0087 0.0115 0.2490 0.1901 0.1407 0.2093 0.2498 0.1908 0.1418 0.2106
5 Youden: 5.260 0.0291 0.0236 0.0221 0.0334 0.7324 0.5510 0.4195 0.6146 0.7481 0.5649 0.4353 0.6393
CP: 6.090 0.0030 0.0074 0.0108 0.0117 0.7691 0.5572 0.4126 0.6364 0.7693 0.5590 0.4178 0.6403
Volume: 5.659 0.0227 0.0215 0.0213 0.0284 0.7726 0.5708 0.4373 0.6328 0.7832 0.5837 0.4537 0.6530
6 Youden: 0.956 −0.0071 −0.0082 −0.0061 −0.0072 0.0789 0.0537 0.0386 0.0603 0.0792 0.0542 0.0390 0.0607
CP: 0.786 −0.0300 −0.0311 −0.0313 −0.0282 0.1065 0.0745 0.0575 0.0833 0.1091 0.0784 0.0625 0.0861
Volume: 0.860 −0.0448 −0.0375 −0.0305 −0.0404 0.1118 0.0764 0.0584 0.0890 0.1183 0.0829 0.0640 0.0955

The samples sizes for the healthy, transitional and diseased populations are given by n, m, and k respectively.

Youden = generalized Youden index, CP = closest to perfection, and Volume = max volume

The RMSE, relative bias and standard deviation estimates are as described in section 4.1.