The relationship between non-suicidal self-injury and temperament in male and female adolescents based on child- and parent-report

Abstract

This study investigates differences in temperament dimensions between community adolescents with and without non-suicidal self-injury (NSSI). Data were collected from 251 adolescents (62.9% females). NSSI was assessed by means of the Self-Harm Inventory (SHI; Sansone, Songer, & Sellbom, 2006) and temperament by means of the Early Adolescent Temperament Questionnaire-Revised (EATQ-R; Ellis & Rothbart, 2001) filled out by the adolescent and his/her parent(s). Almost 27% of the adolescents showed at least one type of NSSI and there were no significant gender differences in the overall frequency of NSSI. However, considering specific NSSI methods, females showed significantly more cutting and scratching compared to males. Self-injurious adolescents showed significant higher scores on Negative Affectivity and lower scores on Effortful Control than adolescents without NSSI. Finally, Lack of Effortful Control and Negative Affectivity were the strongest predictors of NSSI in adolescents. Implications of these findings for the treatment of NSSI in community adolescents are discussed.

Introduction

Non-suicidal self-injury (NSSI) is any socially unaccepted behavior involving deliberate and direct injury to one’s own body surface without suicidal intent (Nock & Prinstein, 2004). Studies (e.g., Ross & Heath, 2002) suggest that 14%–39% of adolescents in community samples engage in NSSI and that male and female adolescents do not significantly differ with respect to NSSI rates in non-clinical samples (e.g., Heath, Toste, Nedecheva, & Charlebois, 2008). However, men and women differ with respect to NSSI method: men report significantly more burning behaviors, whereas women report significantly more cutting and scratching behaviors (e.g., Andover, Primack, Gibb, & Pepper, 2010). The high rate of NSSI in adolescents underscores the need for better understanding NSSI in adolescent samples (Nock & Prinstein, 2004). Associations with temperament have been frequently highlighted as promising avenues for understanding psychopathology (Nigg, 2006). In the present study, we investigate temperamental differences between male/female adolescents with/without NSSI.

While temperament is understudied in NSSI, there are a handful of studies examining personality features common to individuals with NSSI versus those without NSSI. Several studies based on the Big Five Model (Claes et al., 2004, Claes et al., 2010, Hasking et al., 2010, MacLaren and Best, 2010) showed that the presence and/or severity of NSSI was positively related to Neuroticism and negatively related to Agreeableness and Conscientiousness. Other studies (Claes et al., 2003, Janis and Nock, 2009, Simeon et al., 1992), focusing on the personality trait of Impulsiveness, showed that NSSI was positively related to self-reported Impulsiveness. Most of the aforementioned studies however were performed in primarily female samples and were exclusively based on self-reported measures of personality traits.

Therefore, in the present study, we investigate temperament differences between adolescents with/without NSSI in both genders (males/females) and by means of multi-informant assessment of temperament features (adolescents, parents). We will use the temperament model of Rothbart and Derryberry (1981), which is a promising approach to a multidimensional representation of constitutionally based individual differences in reactivity (i.e., excitability or arousability of the behavioral/ physiological systems) and self-regulation (i.e., neural/behavioral processes functioning to modulate this underlying reactivity). In adolescents, four broad temperament factors emerge: Negative Affectivity encompasses mainly frustration and is related to Neuroticism (r = .74). Positive Reactivity manifests as orientation to and exploration of novelty and is related to Extraversion/Sensation Seeking (r = .67). Effortful Control denotes the ability to regulate attention and behavior and is positively related to Conscientiousness (r = .64) and negatively related to Impulsiveness. And finally, Affiliation refers to the desire for closeness with others and is related to Agreeableness (r = .69) (Evans and Rothbart, 2007, Oldehinkel et al., 2004). It is generally acknowledged that reactive and regulative temperament dimensions play an important role in the etiology and maintenance of behavior problems in youth. Muris, Meesters, and Blijlevens (2007), for example, provided support for the notion that in particular the combination of high negative affectivity and low effortful control is associated with high symptom levels in adolescents. Based on the existing literature on personality traits and NSSI, we hypothesized that the presence of NSSI is positively related to Negative Affectivity, and negatively related to Positive Reactivity, Affiliation, and Effortful Control. Linking temperament to NSSI may help to identify high-risk groups, but also yield clues about the etiology of NSSI and potentially effective prevention and intervention actions (Oldehinkel et al., 2004).