Paul Hewitt


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Graduate Student Supervision

Doctoral Student Supervision (Jan 2008 - Nov 2020)
Perfectionism and therapy relationship quality in psychodynamic-interpersonal group psychotherapy (2020)

Perfectionism has been identified as a core vulnerability and maintenance factor in myriad psychopathologies and additionally appears to obstruct the course of improvement from the treatment of that psychopathology. The Perfectionism Social Disconnection Model posits that perfectionism is related to various negative outcomes through the mediating effects of social disconnection. When applied to the therapy realm, one would expect that perfectionism impedes the formation and growth of therapy relationships and that this then leads to worse outcomes from psychotherapy (e.g. less symptomatic improvement). Much of what is known about perfectionism in the context of psychotherapy comes from a series of papers stemming from a single study, the Treatment of Depression Collaborative Research Program (TDCRP, Elkin et al., 1989). These papers support the notion that perfectionism impairs both therapeutic alliance and therapeutic outcomes. This dissertation seeks to evaluate the Perfectionism Social Disconnection Model in the context of psychotherapy and to extend what is known about the relationships between perfectionism, therapy relationship quality, and therapy outcomes beyond the context of individual group treatment of depression using contemporary, empirically validated multidimensional measures of perfectionism. Furthermore, previous studies addressing these issues have mostly conceptualized perfectionism as a static measure. It is unknown if treatments that lead to decreases in perfectionism also improve therapy relationship quality and if those changes account for better therapeutic outcomes. The current paper addresses these questions in a group of 71 patients taking part in a group psychodynamic-interpersonal psychotherapy treatment designed to address issues related to perfectionism. Hypotheses were that 1) pre-treatment perfectionism would be negatively related to initial therapy relationship quality, 2) decreases in perfectionism would be accompanied by increases in therapy relationship quality, and 3) that changes in therapy relationship quality would account for the relationship between decreases in perfectionism and better therapy outcomes. In the current study, these hypotheses were not supported. These null results are discussed in the context of a literature that suggests that perfectionism is related to both worse treatment outcomes and to interpersonal difficulties both in therapy and non-therapy contexts.

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Perfectionistic self-presentation in group therapy: interpersonal behaviours and therapeutic process factors (2018)

The study investigates the associations among perfectionistic self-presentation, interpersonal difficulties, and the process of group therapy based on predictions from the Perfectionism Social Disconnection Model. The study aims to determine whether perfectionistic self-presentation negatively impacts the group therapy process generally and on change over the course of the treatment block. The study also aims to determine whether interpersonal difficulties intervene on the negative associations among perfectionistic self-presentation and group therapy processes. Sixty-nine patients within nine groups attending the Southdown Institute and receiving intensive psychodynamic interpersonal group treatment participated in the study. Patients completed the Perfectionistic Self-Presentation Scale (PSPS; Hewitt et al., 2003), the Inventory of Interpersonal Problems (IIP; Horowitz et al., 1988), the Impact Message Inventory (IMI; Kiesler & Schmidt, 1993) - patient ratings of therapists, the California Psychotherapy Alliance Scales - Group (CALPAS-G; Marmar et al., 1989), and the Curative Climate Inventory (CCI; Furhiman et al., 1986) over the course of one week of daily group therapy. Multilevel modeling analyses were used to analyze direct effects among perfectionistic self-presentation facets and alliance scales and climate factors, as well as indirect effects through interpersonal variables. Perfectionistic self-presentation facets were associated negatively with total alliance and patient contribution scales of the alliance, and positively with interpersonal problems. Perfectionistic self-presentation facets were not associated with change in alliance over the course of the treatment block, with climate factors, or with patients' ratings of therapists' interpersonal impact. Findings suggest that perfectionistic self-presentation influences interpersonal problems and the process of group therapy; however, there was no support for an indirect and intervening role for interpersonal variables in the associations among perfectionistic self-presentation and therapeutic group processes.

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Perfectionism and the cognitive and affective experience of social exclusion (2016)

Perfectionism is a multidimensional personality variable linked to a variety of maladaptive consequences and developmentally rooted in early interpersonal attachments. This has been hypothesized to predispose perfectionistic individuals to more maladaptive outcomes in response to being socially excluded. The current project reviews extant literature on the Comprehensive Model of Perfectionism described by Paul Hewitt, Gordon Flett, and colleagues, its developmental antecedents, and a review of specific vulnerability, diathesis-stress and perfectionism social disconnection models that explain perfectionistic vulnerability to stress, including social exclusion. Hypotheses regarding a moderating effect of perfectionism on cognitive and affective reactions to social exclusion were generated based on the aforementioned models. Using two undergraduate student samples, we exposed participants to a laboratory-based social exclusion experience (Cyberball) under controlled circumstances and performed a comprehensive pre- and post-task assessment of their affective and cognitive experience using a combination of explicit and implicit measures. Results indicated that concern over mistakes, perfectionistic cognitions, perfectionistic self-promotion, and nondisplay of imperfection dimensions of perfectionism were the strongest moderators of the experience of social exclusion in that individuals high on these dimensions experienced amplified post-Cyberball shame, anger, rejection, and self-critical affect and increased negative self-related thoughts, and decreased interdependence. Nondisclosure of imperfection in contrast predicted reduced rejected affect in response to social inclusion. Results are discussed in the context of extant literature in perfectionism and social exclusion domains, and in light of diathesis-stress literature and the Perfectionism Social Disconnection Model, as well as the hypothesized interpersonal underpinnings of perfectionistic behaviour.

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