TABLE 2:
Comparison of Inferior Vena Cava (IVC) Filters Placed and Retrieved During Control and Trial Periods
| IVC Filters | Control Period | Test Period | p |
|---|---|---|---|
| Retrieved < 210 d from insertion | |||
| No. of filters placed and retrieved | 24 | 43 | |
| Mean no. of days from insertion to retrieval | 88.9 | 102.7 | 0.32 |
| Maximum no. of days from insertion to retrieval | 203 | 204 | |
| Minimum no. of days from insertion to retrieval | 16 | 15 | |
| Retrieved ≥ 210 d from insertion | |||
| Filters placed and retrieved | 8 | 8 | |
| Mean no. of days from insertion to retrieval | 368.8 | 242.5 | 0.03 |
| Maximum no. of days from insertion to retrieval | 702 | 319 | |
| Minimum no. of days from insertion to retrieval | 218 | 213 | |
| Not retrieved | |||
| Deceased | 81 | 60 | |
| Reassessment: permanent filter (stop follow-up) | 26 | ||
| Reassessment: continue observation | 14 | ||
| Not followed | 29 | ||
| Total no. of filters placed | 142 | 151 | |
| Total no. of filters retrieved | 32 | 51 | |
| Mean no. of days from insertion to retrieval | 158.8 | 124.6 | 0.17 |