Date of Award
Master of Arts in Psychology
Mark L. Robbins
Living donor kidney transplant (LDKT) is an effective treatment for kidney disease but is underutilized compared to other treatment options. Understanding factors that influence LDKT decision-making has potential to enhance intervention effectiveness and increase pursuit of living transplant. The Transtheoretical Model (TTM) is one model of behavior change that has been applied to transplant decision-making in kidney disease populations. TTM constructs in this area have some empirical support, but evidence suggests that aspects of socioeconomic status also impact the decision to pursue LDKT.
The purpose of this study was to test a cross-sectional model of readiness for pursuing LDKT that was theoretically based in the TTM. Key socioeconomic status (SES) variables were incorporated into the model of TTM change constructs in an effort to study a wider range of variables that may improve understanding of LDKT decision-making.
Data were utilized from the completed baseline sample of Your Path to Transplant, a longitudinal randomized control trial that aimed to enhance decision-making to pursue kidney transplant by delivering TTM Stage-matched expert system coach-delivered feedback (N = 799 ESRD patients).
Prior to model testing, multivariate analysis of variance (MANOVA), analysis of variance (ANOVA), and chi-square tests were performed to examine relationships within TTM constructs (Stage of Change, Decisional Balance, and Self-Efficacy for pursuing LDKT) and between TTM constructs and five socioeconomic variables. Results revealed significant relationships between TTM variables, but no significant relationships were observed between TTM and SES variables. Analyses between SES variables revealed significant relationships with small effect sizes.
Stepwise binary logistic regression was performed to test two models of readiness for pursuing LDKT (Stage of Change: Pre-Action Stages or Action). The replicated TTM model demonstrated expected relationships between independent and dependent TTM constructs. Decisional Balance and Self-Efficacy were related to Stage of Change, and later Stages exhibited significantly greater Self-Efficacy and Pros for pursuing LDKT and significantly lower Cons (χ 2 (3) = 20.83, p < .001, R2 = .047, 95% CI [.01, .08]). In the full model, no statistically significant relationships were observed between TTM constructs and SES variables.
Findings from this study support the successful replication of TTM constructs in a large and diverse sample of ESRD patients. The replicated model demonstrated key differences in perceptions and motivations between patients who were in Action compared to Pre-Action Stages. However, this study was unable to detect significant improvement in model fit with the addition of SES variables. Future research should examine the LDKT readiness model longitudinally, and test for relationships with SES variables over time.
Mushkat, Zoe, "Evaluating Barriers and Transtheoretical Model Constructs in Kidney Transplant Decision-Making" (2018). Open Access Master's Theses. Paper 1235.