Rising rates of mental health problems and nonsuicidal self-injury (NSSI) among adolescents highlight the need for preventive interventions and the lack of evidence regarding such measures. To date, few studies have investigated school-based prevention programs targeting NSSI. In this study, a whole-school preventive intervention was carried out at Swedish lower secondary schools and evaluated in a cluster-randomized controlled trial. The whole-school intervention included classroom-based modules focusing on mental health and NSSI directed at students, psychoeducational webinars on NSSI directed at parents and teachers, and a two-day workshop on NSSI and suicidality for school health staff. Data were collected from students (N = 183, age M = 14.17, SD = 0.55, 58% female) at baseline and three- and six-month post-intervention follow-ups. Analyses revealed a significant decrease in three-month NSSI frequency and a significant difference in mental health-related stigma awareness in the intervention group compared to controls. Regarding other outcomes (NSSI onset, attitudes toward help-seeking, perceived social support, health-related quality of life, emotion regulation and self-criticism), no significant effects were found. Effects moderated by gender and history of NSSI were found, underscoring that the outcomes of universal prevention are not always uniformly distributed. Main conclusions were that whole-school prevention can be effective in reducing NSSI frequency as well as affecting the awareness of mental health-related stigma.

Nonsuicidal self-injury (NSSI), the deliberate harm to one’s body without suicidal intent, is a significant concern among adolescents, often serving as a means to regulate overwhelming emotions. This thesis explores the role of emotion regulation (ER) in the developmental course of NSSI during adolescence, employing quantitative and qualitative methods that include cross-sectional and longitudinal data from both clinical and community samples.

Study I (n = 3,169) investigated the relationship between child abuse and lifetime NSSI in older adolescents aged 16 to 19 years (M = 18.1, SD = 0.5), finding that ER difficulties and trauma symptoms fully mediated this association. This finding underscores ER as a key mechanism linking early adversity to NSSI. Study II (n = 198) examined the development of ER difficulties over time using latent transition analysis, identifying five distinct profiles of ER difficulties among early adolescents aged 13 to 16 years (M age at T1 = 14.20, SD =0.58). Most adolescents reported no or low levels of ER difficulties, and the majority of those reporting difficulties improved over time. One unique and unstable group was identified, marked by high impulsivity during emotional distress. This group decreased in size over time, with parental support and gender emerging as potential influences on ER development. Studies III (n = 21, M age = 21.2, SD = 0.8) and IV (n = 26, M age = 21.2, SD = 0.8) provided a qualitative perspective on NSSI cessation and healthcare experiences, using interviews with young adults with lived experience of NSSI during adolescence. Participants described how internal, relational, and contextual changes facilitated cessation, all of which were interpreted as improving ER. Additionally, their reflections on healthcare emphasized the value of a collaborative understanding, cognitive and emotional growth, and stable and validating therapeutic relationships. These processes can also be viewed as affecting ER, further highlighting its role in healthcare.

In conclusion, this thesis adds to the understanding of how ER specifically relates to the development of NSSI. Focusing on ER could potentially prevent the development of NSSI, even in those with experience of child abuse. Encouragingly, ER is dynamic and modifiable; most adolescents report improvement over time, which can be shaped by factors such as gender and parental support. However, for those who continue self-injuring, the persistence of NSSI may reflect a lack of access to, or reinforcement of, alternative ER strategies. Importantly, the cessation of NSSI is closely tied to the strengthening of ER, often facilitated by meaningful interpersonal connections, supportive environments, and validating therapeutic care. These findings point to the importance of interventions that enhance ER and the broader emotional context surrounding adolescents, with implications for prevention, treatment, and mental health services. For example, ER could be enhanced through mental health professionals’ treatment of patients, using validation and collaboration.

Att skada sig själv avsiktligt, utan att ha för avsikt att dö, är vanligt förekommande hos ungdomar. Självskadebeteende används ofta som en strategi för att hantera känslor. I denna avhandling undersöks vilken roll förmågan att reglera känslor, så kallad emotionsreglering, har i utvecklingen, vidmakthållandet och upphörandet av självskadebeteende under ungdomsåren. Arbetet bygger på både kvantitativa och kvalitativa metoder, och inkluderar data från såväl skolungdomar som unga vuxna med erfarenhet av självskadebeteende och psykiatrisk vård under ungdomsåren.

I Studie I analyserades sambandet mellan olika former av övergrepp under barndomen och självskadebeteende hos ungdomar i åldern 16 till 19 år (n = 3,169). Resultaten visade att erfarenhet av övergrepp under barndomen ökade risken för svårigheter med emotionsreglering och traumasymtom, vilket i sin tur ökade risken för självskadebeteende.

Studie II följde ungdomar i åldern 13-16 år (med medelåldern 14,2 år vid start, n = 198) över tid för att se hur deras förmåga att reglera känslor utvecklades. De flesta ungdomar hade inga eller få självrapporterade emotionsregleringssvårigheter, och generellt förbättrades förmågan med åren. En grupp ungdomar visade dock höga nivåer av svårigheter inom alla områden av emotionsreglering. En annan mindre grupp uppvisade specifika svårigheter med impulsivitet vid emotionell påfrestning. Denna grupp blev mindre över tid, och stöd från föräldrar sågs påverka denna förbättring. Pojkar förbättrades också i sina självrapporterade emotionsregleringssvårigheter i större utsträckning än flickor.

Studie III (n = 21) och IV (n = 26) ger en djupare inblick i emotionsregleringens roll vid självskadebeteende över tid genom intervjuer med unga vuxna (medelålder 21,2 år) som tidigare haft erfarenhet av självskadebeteende. Emotionsreglering tolkades ha en avgörande roll i upphörandet av självskadebeteende, där förändringar i deltagarnas inre, i deras relationer och i deras livssituation möjliggjorde förbättrad emotionsreglering och därigenom upphörandet. I deras erfarenheter av vården framhävdes betydelsen av gemensam förståelse av självskadebeteendet och överenskommelse kring inriktningen på behandlingen, kognitiv mognad och framförallt stabila och validerande terapeutiska relationer – faktorer som indirekt kan ses bidra till en stärkt förmåga att reglera känslor.

Sammantaget visar avhandlingens resultat att emotionsreglering är en nyckelfaktor i både uppkomsten och upphörandet av självskadebeteende. Svårigheter med emotionsreglering förklarar sambandet mellan barndomsövergrepp och självskadebeteende, vilket antyder att insatser som stärker denna förmåga kan förebygga självskadebeteende även hos de med traumatiska barndomserfarenheter. Emotionsreglering framträder som en dynamisk och påverkbar färdighet, där faktorer som kön och föräldrastöd har betydelse. Att sluta skada sig själv hänger nära samman med förbättrad emotionsreglering, vilket i sin tur ofta möjliggörs genom meningsfulla relationer, stödjande miljöer och vård som präglas av förståelse och bekräftelse. Dessa fynd understryker vikten av att preventiva, behandlande och omvårdande insatser inte bara fokuserar på individens förmåga att reglera känslor, utan också på att stärka det stödjande nätverk som omger ungdomar – i familjen, skolan och vården

Background Programs for mental health promotion and prevention of nonsuicidal self-injury (NSSI) in schools have gained increased focus during the last decades, but less is known about adolescents’ experiences of such interventions.

Methods A whole-school preventive intervention targeting mental health and NSSI was delivered to six secondary schools. Adolescents participated in the Youth Aware of Mental Health program combined with an NSSI-focused psychoeducation module. Caregivers and teachers were given online psychoeducation on NSSI, and school health care staff were given a workshop on self-injury. Eleven group interviews (n = 65 participants) were conducted with adolescents (ages 13–15 years, 65% females) exploring participant experiences. Interviews were analyzed using thematic analysis and interpreted in light of a biopsychosocial understanding of adolescence.

Results The analysis generated two main themes. The first theme, Mental health in the context of adolescence, centered around adolescents’ conception of mental health, after having taken part in the intervention, framed in a context of coping with external stressors. The dilemma of autonomy versus help-seeking was also identified as part of the first main theme. The second theme, The who, when, what, and how of the intervention, described adolescents’ experiences of the intervention. This theme included increased awareness and knowledge of mental ill-health. The participants generally agreed that the topics included are important to adolescents and emphasized that the content needs to be relatable. Several factors that influence how a school-based program is received by adolescents were identified, such as who should be targeted and when. Adolescents also identified challenges and gave recommendations for future similar projects.

Conclusions Adolescents generally perceived addressing mental health and NSSI in schools as important. Help-seeking initiatives need to be balanced against adolescents’ need for autonomy when planning mental health prevention and intervention.

BackgroundNonsuicidal self-injury (NSSI) is highly prevalent in adolescents. In survey and interview studies assessing NSSI, methods of assessment have been shown to influence prevalence estimates. However, knowledge of which groups of adolescents that are identified with different measurement methods is lacking, and the characteristics of identified groups are yet to be investigated. Further, only a handful of studies have been carried out using exploratory methods to identify subgroups among adolescents with NSSI.MethodsThe performance of two prevalence measures (single-item vs. behavioral checklist) in the same cross-sectional community sample (n = 266, age M = 14.21, 58.3% female) of adolescents was compared regarding prevalence estimates and also characterization of the identified groups with lifetime NSSI prevalence. A cluster analysis was carried out in the same sample. Identified clusters were compared to the two groups defined using the prevalence measures.ResultsA total of 118 (44.4%) participants acknowledged having engaged in NSSI at least once. Of these, a group of 55 (20.7%) adolescents confirmed NSSI on a single item and 63 (23.7%) adolescents confirmed NSSI only on a behavioral checklist, while denying NSSI on the single item. Groups differed significantly, with the single-item group being more severely affected and having higher mean scores on difficulties in emotion regulation, self-criticism, number of methods, higher frequency of NSSI, higher rates of suicidal ideation and suicidal behavior and lower mean score on health-related quality of life. All cases with higher severity were not identified by the single-item question. Cluster analysis identified three clusters, two of which fit well with the groups identified by single-item and behavioral checklist measures.ConclusionsWhen investigating NSSI prevalence in adolescents, findings are influenced by the researchers' choice of measures. The present study provides some directions toward what kind of influence to expect given the type of measure used, both with regards to the size of the identified group and its composition. Implications for future research as well as clinical and preventive work are discussed.