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Table 3 Summary statistics from 5000 replications: sample mean of point estimates, standard deviation of point estimates, sample mean of standard error estimates, power of test for H 0 : γ = 0 at 5% significance level. Cohort refers to a situation where the covariate in question is collected for every cohort member. SRS refers to subcohort selection with simple random sampling and MORGAM to the subcohort selection procedure described in section 2.3. Weighting method K. & L. refers to Kalbfleisch and Lawless (1988) and ISSP to the inverse subcohort sampling probability weighting as defined in (5).

From: Case-cohort design in practice – experiences from the MORGAM Project

μ γ sampling design weighting method mean sd mean est. sd power
0.2 0.0 cohort - -0.021 0.256 0.247 0.052
   CC (SRS) Prentice -0.001 0.404 0.362 0.076
    K. & L. -0.001 0.424 0.383 0.075
    ISSP 0.001 0.447 0.402 0.070
   CC (MORGAM) Prentice -0.010 0.321 0.310 0.053
    K. & L. -0.009 0.332 0.325 0.050
    ISSP -0.009 0.337 0.331 0.049
  0.3 cohort - 0.296 0.238 0.231 0.283
   CC (SRS) Prentice 0.325 0.391 0.347 0.188
    K. & L. 0.342 0.411 0.367 0.189
    ISSP 0.355 0.438 0.390 0.174
   CC (MORGAM) Prentice 0.313 0.312 0.297 0.207
    K. & L. 0.324 0.323 0.312 0.198
    ISSP 0.329 0.330 0.320 0.191
  0.6 cohort - 0.613 0.226 0.218 0.787
   CC (SRS) Prentice 0.670 0.393 0.337 0.510
    K. & L. 0.705 0.405 0.354 0.514
    ISSP 0.735 0.449 0.384 0.484
   CC (MORGAM) Prentice 0.634 0.309 0.287 0.592
    K. & L. 0.660 0.322 0.303 0.582
    ISSP 0.667 0.331 0.313 0.565
0.4 0.0 cohort - -0.001 0.204 0.200 0.054
   CC (SRS) Prentice 0.006 0.333 0.296 0.075
    K. & L. 0.006 0.349 0.313 0.076
    ISSP 0.007 0.368 0.329 0.071
   CC (MORGAM) Prentice 0.003 0.265 0.251 0.059
    K. & L. 0.003 0.274 0.263 0.058
    ISSP 0.004 0.278 0.268 0.054
  0.3 cohort - 0.314 0.201 0.196 0.372
   CC (SRS) Prentice 0.330 0.327 0.294 0.225
    K. & L. 0.347 0.344 0.311 0.223
    ISSP 0.357 0.365 0.328 0.212
   CC (MORGAM) Prentice 0.317 0.258 0.249 0.253
    K. & L. 0.329 0.266 0.261 0.248
    ISSP 0.332 0.272 0.267 0.238
  0.6 cohort - 0.629 0.200 0.196 0.890
   CC (SRS) Prentice 0.663 0.331 0.294 0.606
    K. & L. 0.700 0.347 0.311 0.604
    ISSP 0.721 0.374 0.332 0.586
   CC (MORGAM) Prentice 0.644 0.261 0.250 0.730
    K. & L. 0.668 0.270 0.262 0.719
    ISSP 0.673 0.277 0.269 0.710