The present study included two groups of student participants. Multi-group analysis (see below) allowed the comparison of the two samples across the same measurement instrument for the identified structural equation model.
The first group included the 167 participants (mean age = 19.9; SD = 5.2; range = 17-57) with 27 males (mean age = 19.1; SD = 1.74) and 139 females (mean age = 20.00; SD = 5.62). For the majority of participants (77%) English was the language spoken at home. The majority of participants were born in Australia (60.8%), followed by Asia (31.3%), Europe (3.0%) and other (4.9%). The data from these participants was used in the previous two studies (see chapter 4 and 5 of this thesis). The second group included 105 student participants (mean age = 19.6; SD = 5.2; range = 17-58) with 20 males (mean age = 22.0; SD = 9.79) and 85 females (mean age = 19.1; SD = 3.28). For the majority of participants (90.5%) English was the language spoken at home. The majority of participants were born in Australia (65.7%), followed by Asia (24.8%), Europe (2.0%) and other (7.5%). Participants from both groups were first year undergraduate psychology students recruited via the University of Melbourne Psychology Department.
Experience of Close Relationships (ECR; Brennan, Clark & Shaver, 1998) is a 36 item self-report questionnaire rated on a 7-point scale. It measures 2 adult attachment-dimensions; attachment-anxiety and attachment-avoidance. The questionnaire was developed in a large sample of undergraduates students (N=1086), with questions derived from a large item-pool consisting of all questions from previously developed measures of attachment. As such, it is considered the 'gold-standard' for measuring adult-attachment (Shaver & Mikulciner, 2002). The measure showed adequate internal consistency for the anxiety (Cronbach's Alpha = .91) and avoidance scales (Cronbach's Alpha = .94; Brennan et al., 1998). In the present study, Cronbach's â•¬â–’ was .90 for the Anxiety subscale and .91 for the Avoidance subscale.
The Padua Inventory - Revised (PI-R, Burns et al., 1996; see chapter 4 for detailed description).
The revised Obsessional Beliefs Questionnaire (OBQ, OCCWG, 2005; see chapter 4 for detailed description).
The Self Perception/Importance Profile for College Students (Neemann & Harter, 1986; see chapter 5 for detailed description). Four of the eleven scales were administered for this study; morality, job competence, school competence, and social acceptability. These subscales were selected due to their hypothesized relationship to OCD (see chapter 5 of this thesis).
World Assumption Scale (WAS; Janoff-Bulman, 1991; see chapter 4 for detailed description). The benevolence of the world and the benevolence of people were the subscales used in this study .
The student participants completed the questionnaire in a classroom within the department. Students were allotted credit for their participation through the research participation program in Melbourne University Psychology Department.