Table 2

Descriptive characteristics of school shooting incidents from 2013 to 2015 in the USA

Characteristics	n	Per cent
N	154
Year of incident
2013	35	22.7
2014	55	35.7
2015	64	41.6
School type
K-12	84	54.6
College	70	45.4
School location
Large central metro	49	31.8
Large fringe metro	28	18.2
Medium metro	40	25.9
Micropolitan (non-metro)	13	8.4
Non-core (non-metro)	4	2.6
Number of fatally injured persons, excluding shooter
Total	57
Median (min–max)	0	0–10
Mean (SD)	0.4	1.0
Number of fatally injured students, excluding shooter
Total	33
Median (min–max)	0	0–8
Mean (SD)	0.2	0.8
Number of non-fatally injured students by gun
Total	88
Median (min–max)	0	0–7
Mean (SD)	0.6	1.1
Number of non-fatally injured students by other means
Total	7
Median (min–max)	0	0–2
Mean (SD)	0.1	0.3
Number of non-fatally injured non-students by gun
Total	28
Median (min–max)	0	0–3
Mean (SD)	0.2	0.5
Number of non-fatally injured non-students by other means
Total	5
Median (min–max)	0	0–3
Mean (SD)	0.03	0.3
Intentional discharge of gun (excludes suicides, misfires, incidental discharges, or warning shots; includes shooting at others)
No	52	33.8
Yes	102	66.2
Shooter and/or victims were inside a building when injured or firing
No	101	65.6
Yes	53	34.4
Gender of shooter
Male	149	99.3
Female	2	1.3
Male and female (two shooters)	1	1.3
Unknown	2	0.6
Age of shooter
11–19 years	36	23.4
≥20 years	42	27.3
Missing information	76	49.4
Shooter status at school
Student	55	35.7
Employee	5	3.3
Other	55	35.7
Missing information	44	28.6
Shooter was reported to be dead after the shooting
No	126	81.8
Yes	28	18.2