The method has been divided into two parts to better fit this study's objectives. Firstly (Part I), the Self-Sacrifice dimension review procedures are developed. Then (Part II), we present information on data collection for verifying the new dimension's psychometric properties.
Part I — Self-Sacrifice dimension revision
This study was divided into six phases to better fit its objectives. We point out that this research paper adopted the same sources used in previous studies, namely: DSM Fifth Edition's Section 3 ([DSM-5]; American Psychological Association 2013), Personality Inventory for DSM-5 ([PID-5]; Krueger et al. 2011) dimensions, Shedler-Westen Assessment Procedure ([SWAP]; Westen and Shedler 1999) dimensions, and Anna Clark’s (1990) dimensions, included in the Schedule for Nonadaptive Personality (SNAP). However, these sources contain few of IDCP's Self-Sacrifice dimension typical elements. Due to that, we have also used references based on Millon's theory at first. The first phase consisted of literature review for verifying self-sacrifice construct-related characteristics based on Millon’s theory. This review considered the Self-Sacrifice dimension to be intimately related to the masochist personality disorder. In other words, there is an excessive lack of concern for oneself (self) and excessive concern for others, evidently presenting along with tendencies to self-sacrifice and help others while doing oneself harm.
In the following phase, dimensions related to Self-Sacrifice were selected to be included in the study's models. Data were collected in a database of dimensions and their respective original characteristics in English, their version in Portuguese independently translated by this study's two authors, and a final consensual version. In the third phase, selected constructs were operationalized, i.e., new items for the Self-Sacrifice dimension were developed based on translated dimensions and selected constructs. In the fourth phase, researchers selected—first independently and then consensually—the items deemed more appropriate. As a result, we came to a set of selected items.
In the fifth phase, items were divided in categories according to their content. Then, still in this same phase, original items from the Self-Sacrifice dimension's original version were also divided in these categories. Thus, we were able to conduct a content comparison between original and new items. Finally, in the sixth phase, based on this previous comparison, new items for the final revised version were selected for the Self-Sacrifice dimension.
Part II — Verifying the Self-Sacrifice dimension's psychometric properties
Participants
This research included 199 subjects conveniently selected at a private university in the State of São Paulo and aged between 18 and 54 years old (M = 26.37; SD = 8.13), 142 of which were women (71.4 %). Most of the subjects had not yet graduated Higher Education (51.8 %) and another large portion of participants had already graduated High School (20.6 %). 10 % of subjects stated to have already underwent or to be currently undergoing psychiatric treatment and only 4.5 % of participants reported using this type of medication. Additionally, 31.2 % of subjects reported having already undergone psychological treatment and 11.6 % of them were still in psychotherapy.
Instruments
The Dimensional Clinical Personality Inventory, developed in 2011 by Carvalho and Primi, was used based on Millon's theory and DSM-IV-TR Axis II categories' diagnostic criteria. The instrument is comprised of 12 personality dimensions, namely: Dependency, Aggressiveness, Mood Instability, Eccentricity, Attention Seeking, Mistrust, Grandiosity, Isolation, Avoidance of Criticism, Self-Sacrifice, Conscientiousness, and Impulsiveness. Items are arranged in a 4-point Likert scale, 1 being 'Strongly Disagree' and 4 being ‘Strongly Agree’. Average time for instrument completion is 25 min.
After administering the instrument, profiles were generated based on 12 personality dimensions. High scores suggest characteristics that gravitate towards pathological personality functioning (Carvalho and Primi 2015). As previously stated, IDCP’s psychometric properties were verified (Carvalho and Primi 2015, in press; Carvalho et al. 2014a, 2014b, 2014c) and generally support this instrument's adequacy.
NEO-PI-R’s Brazilian version was also used in this research (Costa and McCrae 2009). NEO-PI-R is a self-report inventory consisting of 240 items whose goal is to psychologically assess an adult individual's personality in five dimensions: Neuroticism, Extroversion, Openness to Experience, Agreeableness, and Conscientiousness. The instrument contains a 5-point Likert scale that goes from ‘Strongly Disagree’ (1) to ‘Strongly Agree’ (5). This study, however, only took the Neuroticism and Agreeableness dimensions into consideration. NEO-PI-R’s completion time is approximately 30 min. The instrument's Brazilian version manual presents several studies that show acceptable validity evidence and reliability indexes (Costa and McCrae 2009).
Personality Inventory for DSM 5's Brazilian version was also administered (PID-5; Krueger et al. 2011). This instrument is a self-report inventory for assessing pathological personality characteristics consisting of 220 items that represent 25 facets (divided into 5 dimensions) that must be answered in a 4-point Likert scale (0 being ‘Very False or Often False’ and 3 being ‘Very True or Often True’). PID-5 was developed in order to measure Criterion B, figuring in the current proposal for assessment of DSM-5 personality disorders. This study, however, only took the Depressivity and Submission dimensions into consideration.
Procedures
This study was first submitted to an Institutional Review Board and awarded a certificate of presentation for ethical consideration by a local ethics committee (which can be verified through the following protocol number: C.A.A.E. 21992113.1.0000.5514). Following its approval, the data collection phase took place. The instruments were collectively administered in classrooms in a single session for each class, taking 40 min on average for completion. They were also administered individually to participants who were not college students. First, this research study's goals were explained. After subjects had consented to be a part of the study, they signed an Informed Consent Form and answered the study's instruments.
After data collection, data were input in tables used for statistical analyses. Firstly, according to this study's goals, the number of factors to be considered for the exploratory factorial analysis was verified based on a parallel analysis (Hayton et al. 2004; Watkins 2006). For the analysis, R software version 2.15.3 was utilized, once it is compatible with the use of polychoric variables needed.
Based on this analysis, a MPlus software version 6.12 database was created for the exploratory factorial analysis with model adjustment indexes (Exploratory Structural Equation Modeling—E-SEM) and polychoric variables, in addition to obtaining adjustment indexes that indicated structure adequacy based on the study’s population. It is also worth noting that adjustment indexes also suggest population adequacy. Data were compared to results presented by Carvalho and Primi (2015, in press). Lastly, factors chosen to comprise the revised Self-Sacrifice dimension were correlated to NEO-PI-R and PID-5’s dimensions and their respective facets.