Page 107 - Personality disorders and insecure attachment among adolescents

appropriate for use with adults (age 18 or over), though it can be used with younger adolescents with minor modifications (Spitzer et al., 1990). Only the sections which were indicated by the outcome of the VKP were applied in the clinical interview. The SCID-II was administered by trained psychologists. The inter-rater reliability (Cohen’s Kappa) of the SCID-II for categorical diagnoses was reasonable to good (k = .61- 1.00) (Seqal, Hersen, & Van Hasselt, 1994) and the test-retest reliability was also reasonable to good (k = .63) (Weertman, Arntz, & Kerkhofs, 2000). Procedure During an eight-year period (2008-2016), all newly admitted patients were approached to participate in the study. After a verbal description of the treatment protocol to the subjects, written informed consent was obtained according to legislation, the institution’s policy, and Dutch law (Eurec, 2017). All patients (N = 140) agreed to participate and in concordance with the institutional policy, they participated without receiving incentives or rewards. All procedures in this study were aligned with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. According to the treatment protocol, the patients completed a set of web-based questionnaires in the first and last weeks of treatment. Statistical analysis All analyses were performed using the Statistical Package for the Social Sciences (SPSS) version 23.0 (IBM Corp, 2011). Groups were formed consisting of participants with and without NSSI in the year preceding treatment, and of those who started NSSI during treatment. First the no NSSI, NSSI, and NSSI starters group, and the groups with and without measurements at t-2, were compared based on the number of personality disorders using a chi-square. A chi-square test was then performed to compare the frequency of NSSI between participants diagnosed with BPD and participants with other personality disorders. Second, the NSSI groups were compared based on the level of symptoms (SCL-90) using an ANOVA. A Post Hoc test (Bonferroni) was then used for changes in the level of symptoms. Third, the NSSI groups’ coping skills were compared with an ANOVA, post-hoc test, and t-test. Fourth, the method and function of reported NSSI were compared for the NSSI groups using paired t-tests pre and post-treatment. To compare the method of NSSI between participants diagnosed with BPD and participants with other personality disorders, a chi-square test was performed. To compare the method of NSSI used, a list of reported NSSI behaviour was also composed (appendix 3). Because the frequency of NSSI pre and post treatment was assessed at a nominal level analyses were done using a McNemar test. Finally, a binary logistic regression analysis was performed with NSSI at start of treatment versus non-NSSI at the start of treatment as dependent variable. The variables that differed significantly (p<.05) between the two groups were included as independent variables. 103