Table 1.
Design of case-control pool comparisons
| Pool Comparison |
Case-control statusa | N | Mean Age (±sd) |
P-value of mean age difference between cases and controls |
|---|---|---|---|---|
| 1 | Case (good survival) | 101 | 58.9 (8.6) | 0.3038 |
| Control | 182 | 57.7 (10.4) | ||
| 2 | Case (medium survival) | 101 | 59.4 (10.5) | 0.1223 |
| Control | 182 | 57.3 (11.2) | ||
| 3 | Case (poor survival) | 101 | 62.2 (9.5) | 2.5e-4 |
| Control | 181 | 57.3 (12.5) | ||
| 4 | Case (extracted by Qiagen columns) |
39 | 60.5 (9.9) | 0.0288 |
| Control | 90 | 56.2 (10.8) |
a
We stratified the cases in the three large pools by overall survival time. The small subset of 39 case DNAs isolated by Qiagen columns were kept together in one pool.