Family matters : understanding caregiver’s perceptions and knowledge of adolescent nonsuicidal self-injury : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University, Manawatu, Aotearoa New Zealand

Abstract

Caregiver understanding of adolescent nonsuicidal self-injury (NSSI) is critical for early detection, disclosure, and intervention, yet limited research has examined caregivers’ understanding and beliefs regarding their young person’s self-injury. Previous research demonstrates that caregiver perceptions are often discordant with adolescent self-reports, with caregivers frequently underestimating NSSI prevalence or misattributing its functions. This thesis comprises two complementary studies. Study One surveyed n = 204 caregivers (M age = 49.7, SD = 6.10), assessing how demographic and psychological characteristics, NSSI lived experience, and perceptions of their child peers were associated with their perceptions of their child’s NSSI. Results indicated that caregiver perceptions were influenced more by social context, particularly beliefs about peer NSSI, than by their own psychological wellbeing or personal NSSI lived experience. Study Two extended this work by examining 91 matched caregiver-adolescent dyads, allowing direct comparison of caregiver reports with adolescent self-reported NSSI. Concordance between caregiver and adolescent reports was modest, with greater accuracy associated with caregiver gender and family connectedness. Family routines, such as shared mealtimes, were negatively associated with adolescent NSSI, underscoring the importance of relational context. Taken together, findings highlight the need for family-inclusive approaches to NSSI prevention, including caregiver psychoeducation targeting awareness of NSSI and highlighting potential early signs of adolescent distress. Findings have implications for developing culturally responsive, family-inclusive interventions and psychoeducation initiatives, with the potential to improve early identification, support, and treatment access for adolescents who engage in NSSI.