Occurrence of hydrocephalus in HELPS trial to 3 months postrandomization*
| Randomized Treatment | |||||
|---|---|---|---|---|---|
| Hydrogel | Bare Platinum | Absolute Difference | |||
| No. | % | No. | % | 95% CI | |
| Total no. patients randomized | 249 | 250 | |||
| Ruptured aneurysm; no hydrocephalus | 112 | 80.6 | 117 | 84.8 | |
| Ruptured aneurysm; hydrocephalus present | 26 | 18.7 | 21 | 15.2 | +3.5% (−5.4% to +12.4%) |
| Consent withdrawn | 1 | 0.7 | 0 | ||
| Not recently ruptured; no hydrocephalus | 108 | 98.2 | 109 | 97.3 | |
| Not recently ruptured; hydrocephalus present | 2 | 1.8 | 3 | 2.7 | −0.9% (−5.9% to +4.1%) |
Note:—CI indicates confidence interval; TA, target aneurysm (the one on which randomization was based).
* Test for interaction (to find out whether the effect of treatment differs between subgroups), P = 0.5, from logistic regression (ie, there is no evidence that the effect of treatment on hydrocephalus is different in ruptured and unruptured aneurysms).