Inventory of Callous-Unemotional Traits (ICU)
The Inventory of Callous-Unemotional Traits (ICU) is a copyright protected 24-item questionnaire designed to provide a comprehensive assessment of callous and unemotional (CU) traits. These traits have proven to be important for designating a clinically and etiologically important subgroup of children and adolescents with conduct problems, leading to their inclusion as a specifer for the diagnosis of Conduct Disorder in the DSM-5 and a specifier for Conduct-dissocial Disorder and Oppositional Defiant Disorder in the ICD-11. In both cases, those with conduct problems and elevated levels of CU traits are labeled as "with Limited Prosocial Emotions". There are five versions of the scale: ICU-Parent, ICU-Teacher, ICU-Youth, ICU-Parent Preschool, and ICU-Teacher Preschool. Researchers can download and use the ICU free of charge in their work. The only requirements are that the instructions, item wording, and item response format not be changed. Also, copies of any publications using the ICU should be sent to email@example.com to be added to a reference list.
Factor analyses of the ICU consistently document an overarching CU dimension that seems to be captured reliably by summing all items (Ray & Frick, 2020). These analyses do, however, suggest clear method variance that must considered when interpreting factor analyses of the ICU ( Kemp, Ray, Frick, Robertson, Fanti, Essau, Baroncelli, Ciucii, & Bijjtbier, 2022 ). Positively worded (i.e., higher scores indicating higher levels of CU traits) items show lower levels of endorsment and show better discrimination at higher levels of CU traits. Negatively worded items show are endorsed at a higher level and show better discrimination at lower levels of CU traits (Ray et al., 2016). Thus, the total score measures the overarching CU dimension across a broad range of severity and in a way that captures correlates that are separate from more general antisocial behavior.
There is no manual for the ICU. However, below we provide a reference list of published studies using the scale, so that user can see the various ways that it has been scored in research. We also provide present age- and gender-based norms for the total scores for the Inventory of Callous-Unemotional Traits (ICU) – Self-Report Youth Scale (Kimonis et al., 2008), which were derived from five large-scale, community datasets collected in Belgium (Roose et al., 2010), Cyprus (Fanti, Demetriou, & Kimonis, 2013), Germany (Essau, Sasagawa, & Frick, 2006), and Italy (Baroncelli, Roti, & Ciucci, 2018; Ciucci et al., 2014), which led to a combined dataset (N = 4,683) of adolescents ages 11-17. We provide these tables in two formats:
ICU T-score Table in EXCEL format
ICU T-score Table in PDF format
The T-score conversions and percentiles are provided both for the standard 24-item ICU total score and the 22-item ICU total score (with items 2 and 10 excluded), given that the latter two items have not shown consistently strong correlations with total scores across samples in the self-report format (Kimonis et al., 2008). The norms are provided for girls and boys separately and for ages 11-14 years and 15- 17 separately. This was due to the finding of a significant main effect of sex (F (1,4681) = 395.51, p < .001, eta 2 = .08) and age on ICU total score (F (1,4681) = 155.93, p < 0.001, eta 2 = 0.03). In addition, a significant age x gender interaction was observed (F (1 ,4679) = 4.53, p < .05, eta 2 = 0.001). That is, in both the younger and older age groups, boys scored higher than girls on average, but this difference was greater in the older (i.e., ages 15-17) sample. However, there were no significant differences found across the different countries/languages providing data for this normative base. Based on these results, we collapsed the data across countries (i.e., individually provided datasets) but provide separate norm-referenced scores for girls ages 11-14 (N = 1,475) and 15-17 (N = 833) and boys ages 11- 14 (N = 1,444) and 15-17 (N = 931).
We would like to thank our gracious collaborators who collected and provided the data to make this normative database possible and have given permission for us to share these norm-referenced scores.
Baroncelli, A., Roti, B., & Ciucci, E. (2018). The associations between callous-unemotional traits and emotional awareness in youth. Personality and Individual Differences, 120, 247-252.
Cardinale, E. M., & Marsh, A. A. (2020). The reliability and validity of the Inventory of Callous Unemotional Traits: a meta-analytic review. Assessment, 27(1), 57-71.
Ciucci, E., Baroncelli, A., Franchi, M., Golmaryami, F. N., & Frick, P. J. (2014). The association between callous-unemotional traits and behavioral and academic adjustment in children: Further validation of the Inventory of Callous-Unemotional Traits. Journal of Psychopathology and Behavioral Assessment, 36(2), 189-200.
Essau, C. A., Sasagawa, S., & Frick, P. J. (2006). Callous-unemotional traits in a community sample of adolescents. Assessment, 13(4), 454-469.
Fanti, K. A., Demetriou, C. A., & Kimonis, E. R. (2013). Variants of callous-unemotional conduct problems in a community sample of adolescents. Journal of Youth and Adolescence, 42(7), 964-979.
Roose, A., Bijttebier, P., Decoene, S., Claes, L., & Frick, P. J. (2010). Assessing the affective features of psychopathy in adolescence: A further validation of the inventory of callous and unemotional traits. Assessment, 17(1), 44-57.
Determining Elevations on the ICU
The tables with T-scores from the normative sample can provide one method for determine when a child's score on the ICU is greater than is typical in children. The following papers provide data on other methods for determining elevations on the ICU.
Doucherty, M., Boxer, P., Huesmann, L.R., O'Brien, M., & Bushman, B. (2017). Assessing callous-unemotional traits in adolescents: Determining cutoff scores for the Inventory of Callous-Unemotional Traits. Journal of Clinical Psychology, 73, 257-278.
Kemp, E.C., Frick, P.J., Matlasz, T.M., Clark, J.E., Robertson, E.L., Ray, J.V., Thornton, L.C., Myers, T.D., Steinberg, L., & Cauffman, E. (2021). Developing cutoff scores for the Inventory of Callous-Unemotional Traits (ICU) in justice-involved and community samples. Journal of Clinical Child and Acolescent Psychology.
Kimonis, E.R., Fanti, K.A., & Singh, J.P. (2014). Establishing cut-off scores for the parent-reported Inventory of Callous-Unemotional Traits. Archives of Forensic Psychology, 1, 27-48
Key References for Using the ICU
We also have an ICU reference list, which provides the best source of information on the various ways that the ICU has been scored and used in research. Several key studies and reviews describe the development of the ICU and its subscale structure.
Frick, P.J. & Ray, J.V. (2015). Evaluating callous-unemotional traits as a personality construct. Journal of Personality, 83, 710-722.
Kimonis, E.R., Frick, P.J., Skeem, J., Marsee, M.A., Cruise, K., Munoz, L.C. Aucoin, K.J. & Morris, A.S. (2008). Assessing callous-unemotional traits in adolescent offenders: Validation of the Inventory of Callous-Unemotional Traits. International Journal of Law and Psychiatry, 31, 241-251.
Matlasz, T.M., Frick, P.J., & Clark, J.E. (2021). A comparison of parent, teacher, and youth ratings on the Inventory of Callous-Unemotional Traits. Assessment.
Ray, J.V. & Frick, P.J. (2020). Assessing callous-unemotional traits using the total score from the Inventory of Callous-Unemotional Traits: A meta-analysis. Journal of Clinical Child and Adolescent Psychology, 49, 190-199.
Ray, J.V., Frick, P.J., Thornton, L.C., Steinberg, L., & Cauffman, E. (2016). Positive and negative item wording and its influence on the assessment of callous-unemotional traits. Psychological Assessment, 28, 394-404.
There have been a number of approved translations of the ICU. To use one of these translated versions, please contact the author of the appropriate version. The North American Spanish translations can be downloaded here: self-report, parent-report , and teacher-report . If you are interested in making a translation that is not included in this list, please contact Paul Frick at firstname.lastname@example.org.