Participants and procedures
Participants were invited to take part in the study via social communication platforms and mental healthcare professionals across all regions of Lithuania. Inclusion criteria for this study were: (1) ≥18-years-old, (2) experienced at least one traumatic event during lifetime, (3) ≥3 months passed since the last experienced traumatic event, and (4) being able to communicate effectively in Lithuanian language. Data collection was divided into two parts: (1) filling in the self-report measures in a survey and (2) participating in a diagnostic interview with a clinical psychologist or supervised Master’s in Clinical Psychology student. All interviewers were professionally trained in how to administer and evaluate the International Trauma Interview (ITI). Data were collected from October 2020 to June 2021. Due to the COVID-19 (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) pandemic restrictions, the survey was taken using a secure online survey platform, and interviews were conducted via a videoconferencing platform. A more detailed description of the study procedure was reported previously .
The study sample comprised 103 adults, with age range from 18 to 54 years (Mage = 32.64, SDage = 9.36), 83.5% were female. Most participants were Lithuanian (91.3%) and living in an urban area (94.2%). More than half (60.2%) of the sample had a university degree, 17.5% had a non-university higher education degree, and 19.4% had graduated from secondary education. Half of the participants (49.5%) were employed, 14.6% were studying, 15.5% were working and studying simultaneously, and one-fifth of participants (20.4%) were neither working nor studying.
Posttraumatic and Complex Posttraumatic Stress Symptoms
The International Trauma Interview (ITI)  is a semi-structured diagnostic interview based on the ICD-11 PTSD and CPTSD symptom criteria. The ITI is comprised of a description of the index traumatic event(s) and PTSD and DSO symptom assessment sections.
The PTSD symptom assessment section contains the evaluation of the frequency and intensity of the following symptoms: (1) re-experiencing, (2) avoidance, and (3) sense of heightened current threat. Two items have to be evaluated in-depth for each symptom cluster. The severity of each symptom is rated by the interviewer on a five-point scale from absent (= 0) to extreme (= 4).
The DSO symptom assessment section is comprised of the evaluation of (1) affective dysregulation (hyper- or hypoactivation), (2) negative self-concept, and (3) disturbances in relationships. DSO symptoms have to be considered to be trauma related to contribute to diagnosis. The severity of each symptom is evaluated on a five-point scale from not at all (= 0) to extremely (= 4). The PTSD and DSO sections are followed by questions about functional impairment in the persons’ social life, work, or any other important area in life.
A symptom is confirmed as clinically significant if at least one of the two items measuring the symptom is evaluated as ≥2. PTSD can be diagnosed if at least one symptom in each symptom cluster and functional impairment related to the PTSD symptoms are evaluated as ≥2. CPTSD is confirmed if all PTSD diagnostic criteria are met, and at least one symptom in each DSO symptom cluster and functional impairment related to the DSO symptoms are evaluated as ≥2. The ITI requires trauma related DSO symptoms to have been present for at least three months for the diagnosis of the CPTSD. If the index trauma was recent but the individual has pre-existing trauma related DSO symptoms this would qualify.
In the current study, the intensity of the symptoms was evaluated by summing up the scores of each item from the PTSD and DSO symptom clusters. Scores for PTSD and DSO subscales may range from 0 to 24, giving a possible total ITI score range from 0 to 48. The psychometric properties of the Lithuanian version of ITI have previously been found to be robust . In the current analysis, the Cronbach’s alpha coefficients of overall ITI (α = .87), as well as of separate PTSD (α = .81) and DSO (α = .84) sections, were good.
Symptoms of Borderline Pattern
The Borderline Pattern Scale (BPS)  was used to measure borderline personality pattern based on its description in the ICD-11. The BPS comprises four subscales, each with three items. The scale measures affective instability, maladaptive self-functioning, maladaptive interpersonal functioning, and maladaptive regulation strategies. Participants are asked to rate each item on a five-point scale from ‘strongly disagree’ (= 1) to ‘strongly agree’ (= 5). The score of the BPS is calculated by summing all the scores of the scale (ranging from 12 to 60), with a higher score indicating more severe symptoms. The Cronbach’s alpha coefficient of the total BPS in this sample was good (α = .82).
The Suicidal Behaviors Questionnaire-Revised (SBQ-R)  is a brief self-report measure used to evaluate four dimensions of suicidality. The first dimension is lifetime suicide ideation, and suicide attempts evaluated using a four-point scale, from ‘never’ (= 1) to ‘I have attempted to kill myself’ (= 4). The second dimension is the frequency of suicide ideation evaluated using a five-point scale from ‘never’ (= 1) to ‘very often’ (= 5). The third dimension is the threat of suicidal behavior evaluated by how often a person communicated about it to other people, using a three-point scale, from ‘no’ (= 1) to ‘yes, more than once’ (= 3). The last dimension includes the likelihood of suicidal behavior in the future, evaluated on a seven-point scale from ‘never’ (= 0) to ‘very likely’ (= 6). The final score of the SBQ-R is calculated by summing all items (ranging from 3 to 18). A higher score indicates more severe suicide risk. SBQ-R was used previously in studies in Lithuania . The Cronbach’s alpha coefficient of the total SBQ-R scale in the current study was good (α = .81).
An independent-samples t-test, chi-square test for independence (post hoc testing was carried out after choosing the Bonferroni-corrected p-value: .05/3=.017), and bivariate correlations were conducted for the descriptive analyses. Next, we performed mediation analyses  with PROCESS macro v4.0  in SPSS v 26. In the current study, to analyze to what extent each variable mediates the effect between sexual trauma (no experience of sexual abuse=0, experience of sexual abuse=1) and suicide risk (total score), conditional on the presence of the remaining mediators, all variables of interest were simultaneously included in a single parallel mediation model. In the parallel multiple mediator model the mediators were allowed to correlate but not causally influence another mediator in the model . We firstly tested a parallel mediation model with the total scores of complex posttraumatic stress and borderline pattern symptoms included as mediators. Then, in the second model, the mediating role of the total scores of posttraumatic stress, disturbances in self-organization, and borderline pattern symptoms were tested. For the investigation of indirect effects, we selected the percentile method for bootstrapping with 10,000 bootstrap samples and 95% confidence interval [25, 27]. Age, gender (male=0, female=1), and trauma exposure in adulthood (=0) vs. childhood (=1) were included as covariates in the parallel mediation models. We obtained standardized coefficients for all continuous variables. Following the recommendations of Hayes , partially standardized regression coefficients were obtained for dichotomous predictors. As the variable of sexual trauma is dichotomous, the total, direct, and indirect effects are also presented in a partially standardized form.