Various dimensions of perfectionism are proposed, but are seldom integrated. This research develops and tests an integrative theory of perfectionism. Theory predicts personality traits (perfectionistic concerns, but not perfectionistic strivings) precede and predict changes in characteristic adaptations (perfectionistic self-presentation and perfectionism cognitions). Theory also predicts characteristic adaptations precede and predict decreases in subjective well-being (SWB), and are associated with a particular patterned form of perfectionistic narrative identity (i.e., heightened agency and lowered communion). This research tests this integrative theory. A sample of 127 emerging adults (ages 18-25) transitioning to university for the first time was recruited (78% female; 81% Caucasian). A 3-wave, 130-day longitudinal design with quantitative and qualitative components was used. Participants completed questionnaire measures of perfectionism and subjective well-being at all waves, and completed semi-structured life story interviews at Waves 1 and 3. Interviews were transcribed and coded for themes of agency (i.e., themes of achievement, status, power, and self-mastery) and communion (i.e., themes of love, dialogue, caring, and community). Results are presented in Chapters 2, 4 and 5. In Chapter 2, perfectionistic concerns led to increased perfectionistic self-presentation, which in turn led to decreases in SWB. In contrast, perfectionistic strivings did not predict longitudinal change in perfectionistic self-presentation or SWB. These findings supported hypotheses. In Chapter 4, perfectionistic concerns and perfectionism cognitions were positively correlated with agency. Perfectionism cognitions mediated the relationship between perfectionistic concerns and agency. A qualitative thematic analysis revealed themes of agency focused on performance-related concerns, with undertones of self-doubt and unrealistic high standards. These findings supported hypotheses. In Chapter 5, perfectionistic concerns and SWB were unrelated to communion, contrary to expectations. However, themes of communion exhibited good inter-rater reliability, test-retest reliability, and face validity. Hypotheses regarding communion were not supported. Overall, most hypotheses were supported. By conceptualizing perfectionistic personality as a dynamic, multifaceted, and integrated system, there are numerous implications for developmental, clinical, and personality psychology. These implications, along with the strengths and limitations of this study, are discussed.

No description available.

The objectives of this thesis is to explore different approaches of modelling clustered correlated data in the form of repeated or longitudinal counts data leading to a replicated Poisson process. The specific application is from repeated epileptic seizure time to events data. Two main classes of models will be considered in this thesis. These are the marginal and subject or cluster specific effects models. Under the marginal class of models the generalized estimating equations approach due to Liang and Zeger (1986) is first considered. These models are concerned with population averaged effects as opposed to subject-specific effects which include random subject-specific effects such that multiple or repeated outcomes within a subject or cluster are assumed to be independent conditional on the subject−specific effects. Finally we consider a distinct class of marginal models which include three common variants namely the approach due to Anderson and Gill (1982), Wei et al (1989) and Prentice et al. (1981) / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.

The aim of this study was to test for prospective relationships between personality factors measured in elementary school and drinking, smoking, and binge eating during the first year of middle school. Data were collected among adolescents drawn from 23 elementary schools and 15 middles schools in central Kentucky. In a two-wave study, 1,906 children completed questionnaire measures in the spring of 5th grade and the spring of 6th grade. After controlling for sex, pubertal status, and prior engagement in addictive behaviors, it was found that urgency at wave 1 predicted drinking, smoking, and binge eating at wave 2, and low conscientiousness at wave 1 predicted drinking and smoking at wave 2. Risky behaviors during the first year of middle school predict subsequent life problems and subsequent diagnosable addictive disorders. The finding that those behaviors can be predicted by personality factors measured in elementary school indicates the value, for risk researchers and prevention specialists, of focusing efforts on children prior to the onset of adolescence.

Alcohol use in early adolescence is associated with numerous concurrent and future problems, including diagnosable alcohol use disorders. The trait of negative urgency, the tendency to act rashly when distressed, is an important predictor of alcohol-related dysfunction in youth and adults. The aim of this study was to test a model proposed by Cyders and Smith (2008) specifying a puberty-based developmental increase in negative urgency, which in turn predicts subsequent increases in early adolescent drinking. In a sample of 1,910 youth assessed semi- annually from spring of 5th grade through spring of 8th grade, we found support for this model. Pubertal onset was associated with both a mean increase and subsequent rises in negative urgency over time. Drinking frequency at any wave was predicted by prior wave assessments of drinking frequency, negative urgency, and pubertal onset. The slope of increase in drinking also increased as a function of pubertal onset. This model applied to negative urgency but not to other impulsivity-related traits. These findings highlight the importance of personality change in early adolescence as part of the risk matrix for early onset alcohol consumption.

Linear mixed-effects (LME) modeling is a widely used statistical method for analyzing repeated measures or longitudinal data. Such longitudinal studies typically aim to investigate and describe the trajectory of a desired outcome. Longitudinal data have the advantage over cross-sectional data by providing more accuracy for the model. LME models allow researchers to account for random variation among individuals and between individuals. In this project, adolescent health was chosen as a topic of research due to the many changes that occur during this crucial time period as a precursor to overall well-being in adult life. Understanding the factors that influence how adolescents' mental well-being is affected may aid in interventions to reduce the risk of a negative impact. Self-esteem, in particular, has been associated with many components of physical and mental health and is a crucial focus in adolescent health. Research in self-esteem is extensive yet, sometimes inconclusive or contradictory since past research has been cross-sectional in nature. Several factors associated with self-esteem development are considered. Participation in religious services has also been an interest in research for its impact on depression. Depression development and its predictors are evaluated using LME models. Along with this line, this project will address the research problems identified through the following specific topics (i) to investigate the impact of early adolescent anxiety disorders on self-esteem development from adolescence to young adulthood; (ii) to study the role of maternal self-esteem and family socioeconomic status on adolescent self-esteem development through young adulthood; and (iii) to explore the efficacy of religious service attendance in reducing depressive symptoms. These topics present a good introduction to the LME approach and are of significant public health importance. The present study explores varying scenarios of the statistical methods and techniques employed in the analysis of longitudinal data. This thesis provides an overview of LME models and the model selection process with applications. Although this project is motivated by adolescent health study, the basic concepts of the methods introduced have generally broader applications in other fields provided that the relevant technical specifications are met.

Background: Across North America, smoking prevalence is highest among young adults (YAs). Understanding the cessation behaviours of YAs is critical given their higher smoking rates; however, there is a paucity of prospective studies on YA cessation from a population-based sample of smokers. Objectives: This study characterizes younger and older adult smokers as well as identifies the rate of making a quit attempt (QA) and smoking cessation among a representative sample of younger and older adult smokers. Guided by the Social Cognitive Theory (SCT), this study also examines the interpersonal predictors of moving toward smoking cessation among YAs. Methods: Self-report data on 592 YA and 2777 older adult smokers were compiled from the Ontario Tobacco Survey baseline and six-month follow-up interviews. Smoking cessation behaviour was measured as an ordinal variable: made no attempt to quit, made a QA that lasted for less than 30 days, and successfully quit for 30 days or longer. Design-based analyses examined the characteristics of young and older adult smokers. Making a QA and smoking cessation during a six-month follow-up period were modeled according to the SCT constructs while accounting for the complex study design. Results: Young adult smokers were more likely to be men with lower levels of addiction but greater self-efficacy and an intention to quit than their older counterparts. While YA smokers were more likely to make a QA than their older counterparts (25% vs. 17%, respectively), they were no more likely to succeed (14% vs. 10%, respectively). Having an intention to quit smoking and having made two or more lifetime number of QAs predicted making a QA; the use of smoking cessation aids or resources and having knowledge that stop smoking medications make quitting a lot easier also contributed to making an attempt to quit. Self-efficacy, use of smoking cessation aids or resources and having someone to support one‘s QA were positive predictors of quitting whereas having high levels of addiction was a negative predictor of cessation. Conclusions: Young and older adults are distinct types of smokers with different personal and smoking characteristics. Different factors predicted making a QA and smoking cessation among YAs. Smoking cessation interventions for YAs should provide social support and skills to build and maintain self-efficacy to quit. It is critical to ensure YA smokers have effective smoking cessation aids and services that are easily accessible and appropriate for this population. Future research is needed to understand long-term smoking cessation and relapse in this vulnerable population.

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。