Accelerated failure time models for the analysis of competing risks

Competing risks are common in clinical cancer research, as patients are subject to multiple potential failure outcomes, such as death from the cancer itself or from complications arising from the disease. In the analysis of competing risks, several regression methods are available for the evaluation of the relationship between covariates and cause-specific failures, many of which are based on Cox’s proportional hazards model. Although a great deal of research has been conducted on estimating competing risks, less attention has been devoted to linear regression modeling, which is often referred to as the accelerated failure time (AFT) model in survival literature. In this article, we address the use and interpretation of linear regression analysis with regard to the competing risks problem. We introduce two types of AFT modeling framework, where the influence of a covariate can be evaluated in relation to either a cause-specific hazard function, referred to as cause-specific AFT (CS-AFT) modeling in this study, or the cumulative incidence function of a particular failure type, referred to as crude-risk AFT (CR-AFT) modeling. Simulation studies illustrate that, as in hazard-based competing risks analysis, these two models can produce substantially different effects, depending on the relationship between the covariates and both the failure type of principal interest and competing failure types. We apply the AFT methods to data from non-Hodgkin lymphoma patients, where the dataset is characterized by two competing events, disease relapse and death without relapse, and non-proportionality. We demonstrate how the data can be analyzed and interpreted, using linear competing risks regression models.     

Joint modeling of survival time and longitudinal outcomes with flexible random effects

Joint models with shared Gaussian random effects have been conventionally used in analysis of longitudinal outcome and survival endpoint in biomedical or public health research. However, misspecifying the normality assumption of random effects can lead to serious bias in parameter estimation and future prediction. In this paper, we study joint models of general longitudinal outcomes and survival endpoint but allow the underlying distribution of shared random effect to be completely unknown. For inference, we propose to use a mixture of Gaussian distributions as an approximation to this unknown distribution and adopt an Expectation–Maximization (EM) algorithm for computation. Either AIC and BIC criteria are adopted for selecting the number of mixtures. We demonstrate the proposed method via a number of simulation studies. We illustrate our approach with the data from the Carolina Head and Neck Cancer Study (CHANCE).     

The analysis of tumorigenicity data using a frailty effect

In animal tumorigenicity data, the time of occurrence of the tumor is not observed because the existence of the tumor is looked for only at either the time of death or the time of sacrifice of the animal. Such an incomplete data structure makes it difficult to investigate the impact of treatment on the occurrence of tumors. A three-state model (no tumor–tumor–death) is used to model events that occurred sequentially and to connect them. In this paper, we also employed a frailty effect to model the dependency of death on tumor occurrence. For the inference of parameters, an EM algorithm is considered. The method is applied to a real bladder tumor data set and a simulation study is performed to show the behavior of the proposed estimators.     

Effects of Positive and Negative Feedback Sequence on Work Performance and Emotional Responses

Performance feedback has been broadly used within Organizational Behavior Management. However, the specifics regarding the most effective type of feedback still merits careful investigation, including the use of positive and negative sequences of feedback. The current study randomly assigned participants to receive one of the following sequences: (a) positive-positive feedback, (b) positive-negative feedback, (c) negative-positive feedback, and (d) negative-negative feedback. Uniform feedback delivery resulted in higher performance, although inconsistent feedback resulted in lessened negative emotional responses. Recommendations on whether to deliver positive or negative feedback in isolation or combination may depend upon the outcomes currently being prioritized by the organization.     

Korean American social studies teachers’ perceptions and experiences of teaching profession in multicultural urban high schools

This study explores two Korean American social studies teachers’ perceptions and experiences of the teaching profession in multicultural, urban public high schools. Drawing upon critical race theory (CRT) and its interconnection to the model minority myth, the most dominant form of racism against Asians as theoretical underpinnings, this study focuses on: (1) Korean American teachers’ unique experiences of being racial minority educators teaching a contentious subject like social studies within culturally and linguistically diverse school settings; and (2) the influences of the model minority racial stereotype on the teachers’ career choice, professional experiences, and associated coping strategies. This study aims to shed light on the heterogeneous stories and ethnoracially contextualized teaching experiences of Asian American teachers and to provide meaningful insights into and practical implications for the preparation and retention of teachers of color.     

Career Decision Self‐Efficacy of Asian American Students: The Role of Curiosity and Ethnic Identity

This study examined the role of curiosity and ethnic identity in career decision self‐efficacy among Asian American college students. Given that curiosity can promote the process of exploring one’s possible future self, opportunities, and career goals, the authors hypothesized that curiosity would be associated with career decision self‐efficacy, directly or indirectly, through a sense of ethnic identity. Results based on data from 425 Asian American incoming first‐year college students suggest that students with high curiosity tend to present a stronger sense of competence in completing career decision‐related tasks. These findings also confirmed a hypothesis that ethnic identity mediates the association between curiosity and career decision self‐efficacy. Implications for future research and career counseling with Asian American college students are discussed.     

Grandparent caregiving and cognitive functioning among older people: evidence from Korea

Review of Economics of the Household - Caregiving for grandchildren is becoming common and plays an important role in the childcare system in many countries. This study examines whether caregiving...     

Therapist presence in emotionally focused couple therapy blamer softening events: promoting change through emotional experience

The blamer softening event has been associated with successful treatment outcomes in emotionally focused couple therapy. Previous research has highlighted the critical role of softening events and heightened emotional experience in best sessions of emotionally focused couple therapy (EFT). This study examined the effects of a therapist's emotional presence in predicting heightened levels of client emotional experience in blamer softening events. Findings from a detailed analysis of successful and unsuccessful EFT softening attempts demonstrated that a therapist's emotional presence and corresponding evocative vocal quality were more likely to predict heightened levels of client emotional experience in successful softening attempts. Implications of these findings are reviewed in light of EFT research and practice.     

Positive influence of organizational charitable involvement on perceptions of credibility and purchase intention

The influence of charity involvement on perceptions of the organization's communication of charitable activity was examined experimentally. Results suggest that the inclusion of charity statements on an organization's homepage leads to more positive evaluations of organizational credibility and higher purchase intention. In crisis scenarios, charitable involvement neither negatively nor positively influences perceptions of credibility.