Abstract

The objectives of the study were to compare the occurrence of self-injury and suicidal ideations on a sample of highschool students in the City of Zagreb in 2016 and 2021, and to examine the predictors of self-injury and suicidal ideations among high-school students. The participants of the study were 1st grade students from high schools in Zagreb, with 269 students participating in 2016, and 353 in 2021. The most represented group in both samples were the students attending gymnasium, aged 15 on average, with a roughly equal share of boys and girls. The results point to a twofold increase in the occurrence of self-injury among Zagreb high-school students when comparing 2016 (17.0%) and 2021 (29.1%). No significant differences were found in suicidal ideations, although the proportion of participants who reported thinking about committing suicide on at least one occasion was high (27.7% in 2016 and 24.8% in 2021). Adolescent girls reported roughly two times more self-injury (38.2% in 2021) and suicidal ideations (34.2%) than adolescent boys (19.9% self-injury and 15.8% suicidal ideations in 2021). Most self-injuries and suicidal thoughts were reported by young people who estimated that their families had less money than others. The results of hierarchical regression analyses showed that selected sets of predictors accounted for markedly high variance percentages of both self-injuries (43.6%) and suicidal ideations (41.9%). Significant factors for both types of self-aggressive behaviours include lower expression of parental warmth and more parental rejection, as well as non-constructive ways of coping with stress and more negative selfconcept in a certain aspect.