Table 2.

Characteristics of NSSI acts.

Variable	n	%	Mean	SD	Range
Method
Cutting	107
Wound manipulation	28
Scratching	19
Burning/ice burning	9
Head banging/punching self	4
Other	2
More than one method	14	8.28
Motive
To reduce aversive tension or overwhelming emotions	99	45.81
Self-hatred/self-contempt	59
To feel something (other than nothing)	31
Help/attention of others	8
Other reason	20
I don’t know why I self-harmed	9
More than one motive	71
Severity of NSSIa
Mild	47	31.76
Moderate	88	59.46
Severe	13	8.78
Mean painfulness for severity of the woundb
Mild			1.8	2.08
Moderate			2.55	1.76
Severe			4.36	2.5
β-endorphin (ng/ml)c
Pre NSSI	18		11.65	10.82
Post NSSI	476		13.94	11.19
Control condition	236		12.6	12.29
Baseline day	333		14.33	15.47
Variability within person			9.45	7.74	1.09–45.86
Variability between person			14.07	14.26	0.11–161.55

^aSeverity categories: mild: superficial cuts, bruise, and scratching; moderate: not only skin, but also the underlying tissue is damaged, strong bleeding cuts, and 2/3 grade burning; and severe: cuttings until fat tissue, damaged sinews, bone fractures, and inner bleeding.

^bPainfulness was rated on an 11-point Likert scale from 0 (no pain) to 10 (worst imaginable pain).

^cRaw mean values of β-endorphin in ng/ml.