Table 2.
Primary and secondary outcomes and treatment associations for primary decompressive craniectomy.
| Outcome | Adjusted centre-level analyses |
|||||
|---|---|---|---|---|---|---|
| Treatment preference (observed primary DC rates per centre) |
Effect variable | Adjusted value (95% CI)a | ||||
| Quartile 1 (6–12%, n = 53) | Quartile 2 (12–19%, n = 48) | Quartile 3 (19–26%, n = 51) | Quartile 4 (26–67%, n = 48) | |||
| Primary outcome: GOSE at 6 months (median [IQR]) | 3 [1–7] | 3 [1–6] | 3 [1–6] | 3 [1–6] | Common odds ratio | 0.9 (0.7–1.1) |
| Secondary outcomes | ||||||
| In-hospital mortality | 12 (23) | 11 (23) | 21 (41) | 18 (38) | Odds ratio | 1.3 (1.0–3.4) |
| GOSE of 7 or 8 (%) | 13 (25) | 10 (21) | 7 (14) | 8 (17) | Odds ratio | 0.9 (0.7–1.2) |
| GOSE of 5-8 (%) | 17 (32) | 20 (42) | 16 (31) | 17 (35) | Odds ratio | 1.0 (0.8–1.2) |
| GOSE of 4-8 (%) | 20 (38) | 21 (44) | 19 (37) | 22 (46) | Odds ratio | 1.0 (0.8–1.2) |
| QOLIBRI (median [IQR]) at 6 monthsb | Nac | |||||
Abbreviation: CI, confidence interval; DC, decompressive craniectomy; GOSE, Glasgow Outcome Scale Extended; IQR, interquartile range; Na, not available; QOLIBRI, Quality of Life after Brain Injury Scale.
Estimates from random-effect multivariable ordinal/logistic regression with the instrument, adjusted probability of undergoing primary DC as treatment variable. Confounding was furthermore addressed by adjusting for the a-priori defined variables age, GCS, pupil reactivity, hematoma size, contusion presence and midline shift. The adjusted common OR indicates the odds of a higher GOSE score (primary outcome) or experiencing the secondary outcomes, for an increase from the 25th percentile to the 75th percentile of the range in exposure to the centre intervention preferences.
QOLIBRI is a standardised health specific quality of life measure specifically designed for and validated in outcome assesment in patients with brain injury. It is a numerical scale with scores ranging from 0 to 100, with higher scores indicating a better quality of life. The score was available for 19 patients of the primary DC group and 111 of the craniotomy group.
The association could not be estimated due to low numbers (no centers with ≥10 patients in the subcohort).