Date of Award

Summer 2017

Document Type


Degree Name

Doctor of Psychology (PsyD)


Psychology and Behavioral Sciences

First Advisor

Guler Boyraz


Research suggests that engaging in activities that highlight gratitude and optimism can significantly increase well-being. However, additional research is needed to explore characteristics or conditions that optimize the effectiveness of such interventions. The purpose of the present study was to contribute to research in this area by examining the effectiveness each of a gratitude intervention and an optimism intervention on both subjective well-being and psychological well-being among college students. In addition, the current study examined whether personality disposition (i.e., trait gratitude and trait optimism) and social support moderated the effectiveness of these interventions on wellbeing. Data were collected from 144 college students attending a public university in the South. Participants were randomly assigned to three conditions: a gratitude condition, an optimism condition, and a control condition. Prior to engaging in the intervention, participants were instructed to complete a baseline survey, which included informed consent; a demographic questionnaire; and measures of personality dispositions (i.e., gratitude and optimism), social support, and well-being. Participants in experimental groups reflected on an experience or topic intended to elicit gratitude or optimism, while participants in the control group engaged in a similar intervention that involved reflection and journaling on an early memory. Participants engaged in one of these interventions for approximately 20 minutes a day for three consecutive days. After the intervention, all participants completed a survey immediately and four weeks later, which included the well-being measures included in the baseline survey. The results of separate two-way mixed repeated measures analysis of variance (ANOVA) tests indicated there were no significant interactions between time and intervention conditions on the outcome variables; however, the results did show the gratitude intervention was associated with a significant main effect on psychological well-being. Specifically, the gratitude group showed greater mean well-being increases than did the optimism group. Finally, the results of a series of hierarchical regression analyses used to examine potential moderators of the positive psychology intervention – well-being relationships indicated social support moderated the relationship between the optimism intervention and Time 3 subjective well-being. For those in the optimism group, lower baseline social support was related to significant decreases in Time 3 subjective well-being while higher social support at baseline was not significantly associated with changes in subjective well-being at Time 3.