An economic evaluation for the use of decompressive craniectomy in the treatment of refractory traumatic intracranial hypertension

Figures & data

Figure 1. Decision tree for medical management versus decompressive craniectomy for traumatic intracranial hypertension

Table 1. Probabilities associated with terminal nodes of the surgical arm and medical arm of the Markov model

Node	Probability at 12 months in Surgical Arm	Probability at 12 months in Medical Arm
GOS-E 1 (Death)	0.304	0.52
Death in hospital	0.288	0.892
Death outside of hospital	0.712	0.108
GOS-E 2 (Vegetative state)	0.062	0.017
GOS-E 3 (Lower severe disability)	0.18	0.14
GOS-E 4 (Upper severe disability)	0.134	0.039
GOS-E 5 (Lower moderate disability)	0.103	0.078
GOS-E 6 (Upper moderate disability)	0.119	0.123
GOS-E 7 (Lower good recovery)	0.072	0.039
GOS-E 8 (Upper good recovery)	0.026	0.045

Table 2. QALYs derived from GOS-E scores

GOSE	QoL	QALY
1	0.00	0.00
2	0.11	0.11
3	0.41	0.41
4	0.58	0.58
5	0.70	0.70
6	0.81	0.81
7	0.86	0.86
8	1.00	1.00

Table 3. The expected costs and QALYs gained from the two therapeutic branches over the 1-year time horizon

Average expected cost of decompressive craniectomy branch = £16,034.36 Average expected QALYs of decompressive craniectomy branch = 0.41 QALY

Average expected cost of medical management branch = £6,407.00 Average expected QALYs of medical management branch = 0.31 QALY

Table 4. The ICER, NHB and NMB of both the original model and sensitivity analyses

	ICER (£/QALY gained)	NHB (QALYs)	NMB (£)
Original model	96,155.67	− 0.22	− 6,623.68
Sensitivity analysis 1	38,764.58	− 0.02	− 706.30
Sensitivity analysis 2	195,894.01	− 0.55	−16,609.75

Figure 2. The redesigned Markov model, in which GOS-E outcomes have been categorized into either ‘favorable’ or ‘unfavorable’

Figure 3. One-way sensitivity analysis with proportional re-distribution of patients from the medical arm into the surgical arm

Figure 4. Cost-effectiveness plane

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article and its supplementary materials.