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. 2015 Nov 20;182(12):1047–1055. doi: 10.1093/aje/kwv152

Table 2.

Simulation Results Based on Complete Data Generated Using Young et al.'s (18) Algorithm, in Which Every Sixth Measurement of Both the Confounder and the Exposure Are Observed and the Remaining 5 Measurements Are Missing

φ, Sample
Size (n),
and Statistic
Analytical Approach
Complete
Data
Available-
Casea
LOCF Multiple
Imputationb
0
100
  Bias 0.013 0.090 0.046 0.002
  SD 0.305 0.637 0.528 0.225
  rMSE 0.305 0.643 0.530 0.225
 500
  Bias −0.005 0.050 0.062 0.003
  SD 0.139 0.238 0.231 0.131
  rMSE 0.139 0.243 0.239 0.131
−log(3)
 100
  Bias −0.037 −0.043 0.885 0.898
  SD 0.354 0.699 0.639 0.265
  rMSE 0.356 0.700 1.092 0.936
 500
  Bias −0.023 0.017 0.852 0.912
  SD 0.170 0.287 0.280 0.163
  rMSE 0.172 0.288 0.897 0.926
log(2)
 100
  Bias 0.043 0.161 −0.422 −0.574
  SD 0.284 0.666 0.509 0.208
  rMSE 0.287 0.685 0.662 0.611
 500
  Bias 0.039 0.097 −0.437 −0.575
  SD 0.123 0.250 0.173 0.140
  rMSE 0.129 0.268 0.470 0.592

Abbreviations: LOCF, last observation carried forward; rMSE, root mean squared error; SD, standard deviation.

a Some estimates were excluded when calculating the performance statistics (bias, SD, and rMSE) because of an excessively high (≥10) odds ratio; for each (φ, n) pair, the following numbers of estimates were excluded: (0, 100): 0; (0, 500): 0; (−log(3), 100): 13; (−log(3), 500): 0; (log(2), 100): 1; (log(2), 100): 0.

b Some estimates were excluded when calculating the performance statistics (bias, SD, and rMSE) because of an excessively high (≥10) odds ratio; for each (φ, n) pair, the following numbers of estimates were excluded: (0, 100): 8; (0, 500): 2; (−log(3), 100): 6; (−log(3), 500): 5; (log(2), 100): 6; (log(2), 100): 1.