Description

The Illinois Bully Scale (IBS-18) is a psychometric instrument designed to assess the frequency and severity of bullying behaviors and bullying victimization among children and adolescents. Developed by Dorothy L. Espelage and colleagues, the scale evaluates involvement in bullying from multiple perspectives, including perpetration, victimization, and engagement in physical fighting. It is widely used in educational and psychological research to identify students at risk and to examine the prevalence and characteristics of school bullying.

The IBS-18 consists of 18 items organized into three subscales: Bullying, Victimization, and Fighting. The instrument measures a broad range of aggressive behaviors, including physical aggression, verbal harassment, intimidation, social exclusion, and peer conflict. By assessing both bullying and victimization experiences, the scale provides a comprehensive evaluation of students’ involvement in aggressive peer interactions.

The questionnaire is extensively used in school psychology, educational research, developmental psychology, public health, and violence prevention studies, contributing to the understanding of bullying behaviors and their psychological, social, and academic consequences.

Analysis and Use of Data

The analysis of the IBS-18 is based on participants’ responses to 18 items, which are typically rated using a Likert-type frequency scale according to the administration guidelines.

The instrument evaluates three principal domains:

  • Bullying: Frequency of engaging in bullying behaviors toward peers.
  • Victimization: Frequency of experiencing bullying by other students.
  • Fighting: Involvement in physical fights and aggressive confrontations.

The collected data can be used to investigate relationships between bullying involvement and variables such as anxiety, depression, self-esteem, emotional regulation, aggression, school climate, academic performance, peer relationships, psychological well-being, and quality of life. Researchers also use the scale to compare bullying prevalence across age groups, schools, educational settings, and cultural contexts, as well as to evaluate the effectiveness of anti-bullying interventions.

Psychometric evaluation of the IBS-18 typically includes assessment of internal consistency using Cronbach’s alpha, test–retest reliability, and construct validity through exploratory or confirmatory factor analysis. Convergent and discriminant validity are often examined through comparisons with other measures of aggression, peer victimization, behavioral problems, and school adjustment.

Objective

The primary objective of the Illinois Bully Scale (IBS-18) is to provide a reliable and valid assessment of bullying involvement among students. More specifically, the instrument aims to:

  • Assess the frequency of bullying behaviors.
  • Evaluate experiences of victimization.
  • Measure involvement in physical fighting.
  • Support research investigating the causes and consequences of bullying.
  • Facilitate the development and evaluation of school-based bullying prevention and intervention programs.

Scoring

The IBS-18 consists of 18 items scored according to the administration guidelines of the instrument, typically using a Likert-type frequency scale.

Total and subscale scores are calculated by summing participants’ responses for the Bullying, Victimization, and Fighting dimensions. Higher scores indicate greater involvement in bullying-related behaviors, whether as a perpetrator, a victim, or through participation in physical aggression. Lower scores reflect less frequent involvement in bullying incidents and aggressive peer interactions.

For research applications, it is recommended that the psychometric properties of the instrument be evaluated using Cronbach’s alpha, test–retest reliability, and construct validity analyses.

Applications

The Illinois Bully Scale is widely used in school psychology, educational psychology, developmental psychology, public health, and violence prevention research. It has been applied in studies investigating bullying, peer victimization, aggression, school violence, emotional adjustment, mental health, academic achievement, school connectedness, and psychosocial development.

In educational practice, the IBS-18 assists teachers, school psychologists, counselors, and researchers in identifying students involved in bullying, monitoring bullying trends within schools, evaluating prevention programs, and developing evidence-based interventions that promote safe and supportive school environments.

References

Espelage, D. L., & Hong, J. S. (2017). Bullying in Middle School: Current Status and Future Directions. Journal of School Health, 87(8), 601–607.

Espelage, D. L., & Holt, M. K. (2001). Bullying and Victimization During Early Adolescence: Peer Influences and Psychosocial Correlates. Journal of Emotional Abuse, 2(2–3), 123–142.

Espelage, D. L., & Swearer, S. M. (2003). Research on School Bullying and Victimization: What Have We Learned and Where Do We Go from Here? School Psychology Review, 32(3), 365–383.