Table 3.
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, the Remaining 5 Measurements Are Missing, and Data on 15% of Outcomes Are Missing
| φ, Sample Size (n), and Statistic |
Analytical Approach |
|||
|---|---|---|---|---|
| Complete Data |
Available- Casea |
LOCFb | Multiple Imputationc | |
| 0 100 |
||||
| Bias | 0.009 | 0.072 | 0.057 | 0.129 |
| SD | 0.293 | 0.579 | 0.746 | 0.662 |
| rMSE | 0.293 | 0.584 | 0.748 | 0.674 |
| 500 | ||||
| Bias | 0.004 | 0.076 | 0.048 | 0.118 |
| SD | 0.135 | 0.250 | 0.356 | 0.338 |
| rMSE | 0.135 | 0.261 | 0.359 | 0.358 |
| −log(3) | ||||
| 100 | ||||
| Bias | −0.030 | −0.025 | 0.225 | 0.023 |
| SD | 0.360 | 0.730 | 0.953 | 0.925 |
| rMSE | 0.361 | 0.730 | 0.979 | 0.925 |
| 500 | ||||
| Bias | −0.019 | 0.046 | 0.281 | 0.199 |
| SD | 0.163 | 0.277 | 0.399 | 0.458 |
| rMSE | 0.164 | 0.281 | 0.488 | 0.500 |
| log(2) | ||||
| 100 | ||||
| Bias | 0.054 | 0.145 | −0.163 | 0.209 |
| SD | 0.286 | 0.638 | 0.640 | 0.789 |
| rMSE | 0.291 | 0.654 | 0.660 | 0.816 |
| 500 | ||||
| Bias | 0.029 | 0.087 | −0.203 | 0.188 |
| SD | 0.123 | 0.267 | 0.250 | 0.493 |
| rMSE | 0.126 | 0.281 | 0.322 | 0.527 |
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): 1; (0, 500): 0; (−log(3), 100): 13; (−log(3), 500): 0; (log(2), 100): 0; (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): 0; (0, 500): 0; (−log(3), 100): 2; (−log(3), 500): 0; (log(2), 100): 1; (log(2), 100): 0.
c 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): 1; (0, 500): 1; (−log(3), 100): 13; (−log(3), 500): 3; (log(2), 100): 1; (log(2), 100): 1.