The purpose of this study was to validate and verify the Korean version of the Inventory of Statements about Self-Injury (ISAS) to better understand the psychopathological characteristics of nonsuicidal self-injury (NSSI) among young adults.
A total of 539 Korean adults (age: 19 to 30 years; 343 participants with a history of NSSI) completed a self-report online survey regarding NSSI validation research. The test-retest reliability, internal consistency, concurrent validity, and factor analysis of the ISAS behavioral scales and the ISAS functional scales were examined. The factor structure and construct validity were evaluated by performing exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA).
The results demonstrated the good internal consistency and temporal stability of the Korean version of the ISAS. The EFA revealed that the NSSI functions exhibited a two-factor structure: intrapersonal functions and interpersonal functions. The CFA also confirmed that the model fitness indicators of the 2-factor structure were appropriate. In addition, the ISAS functional scales were related to increased suicidal ideations and decreased resilience in participants with a history of NSSI.
The current findings suggest that the Korean version of the ISAS is a robust measure of NSSI behaviors. Further research is needed to investigate the causal relationship between clinical symptoms, given the significant correlation between self-reported NSSI and suicidal ideation and decreased resilience.
Nonsuicidal self-injury (NSSI) is deliberate and repetitive self-harming behaviors aimed at the destruction of one’s own body tissues or organs. NSSI manifests as a wide variety of behavioral patterns. Typical NSSI behaviors include cutting or carving the skin, burning the skin or deliberately fracturing one’s bones. Sometimes self-injurious behaviors are easily hidden or passed off as accidents [
NSSI behaviors occur and are perpetuated in relation to a series of functions: intrapersonal functions (i.e., escaping from unwanted ideations or feelings or leading to desired feelings or stimulation) and interpersonal functions (i.e., leading to peer bonding or escaping from undesired interpersonal stimuli) [
To explore various functions that have a great influence on the onset or maintenance of NSSI behaviors, the Inventory of Statements about Self-Injury (ISAS) was developed to cover more extensive functions that drive NSSI and are related to sensation seeking, coping with dissociative experiences or suicidal ideation, and establishing personal boundaries [
The current study was conducted to confirm the factor structure, internal consistency, test-retest reliability, and concurrent validity of the Korean version of the ISAS. We also explored the link between NSSI patterns with suicidal ideation and resilience, which are closely related to self-destructive behavior [
Consistent with the validation process for the original versions of the NSSI, which examined young adults with the most frequent levels of depression [
1) age younger than 19 or older than 30 years, 2) display of comprehension problems, and 3) lack of motivation or cooperation in responding to the questionnaires.
Eligible participants were asked to independently complete the online survey via the internet. Of the 757 participants, 74 respondents were excluded due to the omission of the ISAS and 144 respondents were excluded due to the omission of other scales. The final sample consisted of 196 controls (control group: never engaged in NSSI during their lifetime) and 343 NSSI participants (NSSI group: engaged in NSSI more than once during their lifetime [
The study protocol was approved by the Institutional Review Board of Chung-Ang University (IRB No. 1041078-2017 06-BRSB-127-0C), and we obtained written informed consent from all participants in this study.
NSSI behaviors and functions were assessed using the Korean version of the ISAS (
The Korean version of the ISAS (
The FASM was developed by Lloyd et al. [
Because suicidal ideation is one of the clear predictors of suicidal attempts, further research is needed on the relevance of suicidal ideation to NSSI behaviors [
Resilience is defined as the ability to bounce back or recover from stress, adapt to stressful situations, and function above the norm despite untoward stress and adversity [
All data were assessed using a SPSS 18 for Windows (SPSS Inc., Chicago, IL, USA) spreadsheet. In terms of reliability, the test-retest reliability and internal consistency were investigated. To examine the retest reliability, 70 individuals were randomly selected from the total sample to retake the Korean version of the ISAS 4 weeks after the first administration. Thirty-five subjects completed the 4-week retest and were included in the test-retest analysis.
In addition, Mplus and AMOS 23 were used to perform exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. EFA was conducted first to identify the underlying structure of the ISAS by adopting the maximum likelihood extraction method with an oblique promax rotation.39 Consistent with a previous study [
Regarding the CFA model, we followed the recommendations of Hu and Bentler [
Of the 539 participants, 66.2% (n=357) were female, and 0.7% (n=4) were “sex unspecified.” A total of 48% (n=262) of the participants were aged 19 to 22 years, 40.2% (n=217) were aged 23 to 26 years, and 11.2% (n=60) were aged 27 to 30 years. Regarding education level, the participants reported the following: 0.2% (n=1) had “not completed high school,” 3.3% (n=18), were a “high school graduate,” 67.7% (n=365) were “in university,” 20.4% (n=110) were a “university graduate,” and 8.3% (n=45) were “beyond graduate school.” In terms of self-reported socioeconomic status, the participants reported the following: 7.1% (n=38) were low, 22.3% (n=20) were low-medium, 40.3% (n=217) were medium, 26% (n=140) were medium-high, and 4.5% (n=24) were high.
The test-retest reliability and internal consistency were analyzed to verify the reliability of the Korean version of the ISAS. The internal consistency of ISAS section 1 was excellent (Cronbach’s alpha=0.85, n=539). Pearson correlations between the overall score and each item ranged from 0.40 (carving) to 0.77 (banging or hitting oneself), and the median was 0.60 (severe scratching) (all p<0.001) (
The four-week test-retest reliability of section 1 was examined using data from 35 participants who were randomly selected from among all participants. The test-retest correlation of the overall score was significantly high (r=0.90, p<0.001). The test-retest correlations for each behavior varied from 0.50 (sticking oneself with needles) to 0.94 (cutting), with a median of 0.74 (pinching). All correlations were positive and statistically significant (p<0.001).
Pearson correlations were calculated between the ISAS behavioral scales and the behavioral frequency of the NSSI measured by the FASM (item “A”) to investigate the concurrent validity. The correlation between the 2 measurements was good (r=0.74, p<0.001) (
Cronbach’s alpha was 0.92 for the Korean version of ISAS section 2, indicating excellent internal consistency reliability. The range was 0.24 (item 34) to 0.70 (item 29), and the median was 0.49 (item 11) (all p<0.001) (
The overall test-retest correlation was 0.91; and the test-retest correlations for interpersonal and intrapersonal functions were 0.84 and 0.92, respectively (all p<0.001).
Exploratory Factor Analysis (EFA)
Inspection of the scree plot and eigenvalues indicated a 2-factor structure accounting for 40.57% of the total variance. Regarding the 2-factor structure, factor 1 had an eigenvalue of 13.01 and included interpersonal functions. Factor 2 had an eigenvalue of 2.76 and included intrapersonal functions. The intercorrelation between the 2 factors was adequate (r=0.58, p=0.05). Thirty-four out of 39 items loaded on the interpersonal or intrapersonal functions consistent with previous studies [
Confirmatory Factor Analysis (CFA)
The current analysis defined the following 13 observed variables and 2 implicit factors of the Korean version of the ISAS functional scales: [
The Pearson correlation for the ISAS functional scales and NSSI functions assessed by the FASM (item “H”) was calculated to investigate concurrent validity. The correlation between the overall score of ISAS section 2 and the FASM was good (r=0.77, p<0.001; intrapersonal function: r=0.75, p<0.001; interpersonal function: r=0.70, p<0.001).
Correlations between the Korean version of the ISAS and other clinical scales were analyzed to better understand the psychopathological characteristics related to NSSI. Regarding the NSSI behaviors (ISAS section 1), the frequency of NSSI behavior showed a positive correlation with suicidal ideation (r=0.48, p<0.001) and a negative correlation with resilience (r=-0.33, p<0.001). More specifically, intrapersonal function was related to high suicidal ideation (r=0.62, p<0.001) and low resilience (r=-0.45, p<0.001). Additionally, interpersonal function was related to high suicidal ideation (r=0.47, p<0.001) and low resilience (r=-0.38, p<0.001) (
Just a decade ago, self-injury was regarded as a dramatic gesture by immature individuals who would seek the attention of others or fail to regulate their own emotions [
The main purpose of this study was to examine the psychometric properties of the Korean version of the ISAS [
The results of this study are summarized as follows. First, the findings support the good reliability and validity of the Korean version of the ISAS behavioral scales, which were originally designed to investigate the type and lifetime frequency of 12 NSSI behaviors. The statistical properties of the Korean version of the ISAS behavioral sections were similar to those found in the original study [
Regarding the second section of the ISAS, we confirmed the sufficient reliability and validity, which is consistent with the findings of the original, Turkish, and Mexican studies [
The results of the correlation analysis revealed that the self-reported NSSI functions measured in the Korean version of the ISAS were significantly correlated with problematic clinical features, such as suicidal ideation and reduced resilience. In other words, the participants who exhibited more suicidal ideation and less resilience reported more functions for their self-injurious behaviors. As previous research has illustrated, vulnerable individuals may initiate NSSI when they have difficulty coping with internal and external environments [
Certain limitations were observed in this study. First, this study was conducted with a convenient sample of individuals who could access the internet, and participation in research was available only through the internet. Most of the participants were university students living in the capital area, which prevents the generalization of the findings to other populations. Second, although the validation analyses used are widely accepted as robust research methodologies, the findings were derived from limited self-reported data. Therefore, to thoroughly identify antecedents and precedents for NSSI in Korea, further research should include different samples and methodologies. Because NSSI can lead to later suicidal behaviors, historical suicide attempts should be included in future studies.
In conclusion, the Korean version of the ISAS, which measures the frequency and function of NSSI, is a reliable and valid measure of the NSSI behaviors in Korean adults. The Korean version of the ISAS functional scales also has a 2-factor structure that includes intrapersonal and interpersonal functions, which is consistent with previous studies. The use of various psychological measures extends the research area of mental health. We hope that a more sophisticated approach will become available for both a clinical setting and research setting based on the results presented here on the relationships among NSSI, suicidal ideation and weakened resilience as well as the adequate psychometric properties of the Korean version of the ISAS.
The online-only Data Supplement is available with this article at
This work was supported by the National Research Foundation of Korea (NRF) by a grant funded by the Korean government (NRF-2017R1C1B50 18400), and by the Chung-Ang University Research Grants in 2018.
The authors have no potential conflicts of interest to disclose.
Scree plot for the exploratory factor analysis of the Inventory of Statements About Self-injury.
The structure of the Inventory of Statements About Self-injury functions.
Correlations between the overall score and each item in the ISAS section 1 (N=539)
ISAS each behavior | ISAS section 1 overall |
---|---|
Banging or hitting self | 0.77 |
Biting | 0.75 |
Burning | 0.44 |
Carving | 0.40 |
Cutting | 0.56 |
Interfering with wound healing | 0.63 |
Pinching | 0.72 |
Pulling hair | 0.64 |
Rubbing skin against rough surface | 0.58 |
Severe scratching | 0.60 |
Sticking self with needles | 0.61 |
Swallowing dangerous substances | 0.50 |
Else | 0.44 |
p<0.05.
ISAS: Inventory of Statements about Self-Injury
Correlations between the Inventory of the FASM and the ISAS section 1 (overall score and each item) (N=539)
ISAS each behavior | FASM |
---|---|
ISAS section 1 overall | 0.74 |
Banging or hitting self | 0.59 |
Biting | 0.59 |
Burning | 0.35 |
Carving | 0.17 |
Cutting | 0.59 |
Interfering with wound healing | 0.42 |
Pinching | 0.44 |
Pulling hai | 0.41 |
Rubbing skin against rough surface | 0.34 |
Severe scratching | 0.50 |
Sticking self with needles | 0.43 |
Swallowing dangerous substances | 0.34 |
Else | 0.34 |
p<0.05.
ISAS: Inventory of Statements about Self-Injury, FASM: Functional Assessment of Self-Mutilation
Correlations between the overall score and each item in the ISAS section 2 (N=539)
Each function (number) | ISAS section 2 overall |
---|---|
01. When I self-harm, I am calming myself down. | 0.29 |
02. When I self-harm, I am creating a boundary between myself and others. | 0.65 |
03. When I self-harm, I am punishing myself. | 0.55 |
04. When I self-harm, I am giving myself a way to care for myself (by attending to the wound). | 0.44 |
05. When I self-harm, I am causing pain so I will stop feeling numb. | 0.45 |
06. When I self-harm, I am avoiding the impulse to attempt suicide. | 0.55 |
07. When I self-harm, I am doing something to generate excitement or exhilaration. | 0.39 |
08. When I self-harm, I am bonding with peers. | 0.30 |
09. When I self-harm, I am letting others know the extent of my emotional pain. | 0.41 |
10. When I self-harm, I am seeing if I can stand the pain. | 0.48 |
11. When I self-harm, I am creating a physical sign that I feel awful. | 0.49 |
12. When I self-harm, I am getting back at someone. | 0.38 |
13. When I self-harm, I am ensuring that I am self-sufficient. | 0.38 |
14. When I self-harm, I am releasing emotional pressure that has built up inside of me. | 0.50 |
15. When I self-harm, I am demonstrating that I am separate from other people. | 0.66 |
16. When I self-harm, I am expressing anger towards myself for being worthless or stupid. | 0.62 |
17. When I self-harm, I am creating a physical injury that is easier to care for than my emotional distress. | 0.66 |
18. When I self-harm, I am trying to feel something (as opposed to nothing) even if it is physical pain. | 0.62 |
19. When I self-harm, I am responding to suicidal thoughts without actually attempting suicide. | 0.61 |
20. When I self-harm, I am entertaining myself or others by doing something extreme. | 0.43 |
21. When I self-harm, I am fitting in with others. | 0.34 |
22. When I self-harm, I am seeking care of help from others. | 0.50 |
23. When I self-harm, I am demonstrating I am tough or strong. | 0.48 |
24. When I self-harm, I am proving to myself that my emotional pain is real. | 0.68 |
25. When I self-harm, I am getting revenge against others. | 0.49 |
26. When I self-harm, I am demonstrating that I do not need to rely on others for help. | 0.49 |
27. When I self-harm, I am reducing anxiety, frustration, anger, or other overwhelming emotions. | 0.51 |
28. When I self-harm, I am establishing a barrier between myself and others. | 0.62 |
29. When I self-harm, I am reacting to feeling unhappy with myself or disgusted with myself. | 0.71 |
30. When I self-harm, I am allowing myself to focus on treating the injury, which can be gratifying or satisfying. | 0.29 |
31. When I self-harm, I am making sure I am still alive when I don’t feel real. | 0.57 |
32. When I self-harm, I am putting a stop to suicidal thoughts. | 0.62 |
33. When I self-harm, I am pushing my limits in a manner akin to skydiving or other extreme activities. | 0.37 |
34. When I self-harm, I am creating a sign of friendship or kinship with friends of loved ones. | 0.24 |
35. When I self-harm, I am keeping a loved one from leaving or abandoning me. | 0.51 |
36. When I self-harm, I am proving I can take the physical pain, | 0.48 |
37. When I self-harm, I am signifying the emotional distress I’, experiencing. | 0.68 |
38. When I self-harm, I am trying to hurt someone close to me. | 0.47 |
39. When I self-harm, I am establishing that I am autonomous/independent. | 0.59 |
p<0.05.
ISAS: Inventory of Statements about Self-Injury
Correlations between the ISAS and other scales
ISAS section 1 | ISAS section 2 | Intrapersonal functions | Interpersonal functions | |
---|---|---|---|---|
BSI | 0.48 |
0.57 |
0.62 |
0.17 |
KRQ-30 | -0.33 |
-0.43 |
-0.37 |
-0.47 |
p<0.05.
ISAS: Inventory of Statements about Self-Injury, ISAS section 1: NSSI behaviors, ISAS section 2: NSSI functions, BSI: Beck Scale for Suicidal Intention, KRQ-53: Korean Resilience Questionnaire-53