Table 3.

Demographic data of the neurosurgical cohort in the first-year survey in the JND

Main classification	No.		Age	Men (%)	In-hospital mortality (%)	Length of hospital stay
	Case No.	%	Mean ± SD			Median ± IQR
Cerebrovascular diseases	72,607	41.0	67.1 (14.9)	50.5	6.0	20 (11–37)
Brain tumor	22,641	12.8	58.6 (18.2)	48.3	1.8	20 (14–36)
Neurotrauma	45,216	25.5	76.0 (14.3)	68.2	3.4	10 (8–19)
Hydrocephalus/Developmental Anomalies	9,309	5.3	54.9 (30.7)	51.2	1.6	17 (12–30)
Spinal and peripheral nerve disorders	17,969	10.1	66.0 (15.4)	59.6	0.3	16 (11–26)
Functional neurosurgery	6,643	3.7	55.0 (19.7)	45.1	0.1	13 (10–19)
Encephalitis/Inflammatory/Miscellaneous diseases	2,799	1.6	60.8 (19.8)	54.2	2.5	23 (12–44)

JND: Japan Neurosurgical Database, SD: standard deviation, IQR: interquartile range.