Factors Associated with Opting Out of an Unrelated Hematopoietic Stem Cell Donor Registry: Differences and Similarities across Five Key Groups of Young Race/Ethnically Diverse Potential Donors in the United States

Young adults from underserved racial/ethnic groups are critically needed as unrelated hematopoietic stem cell (HSC) donors, yet they are more likely than other groups to opt out of donation after having matched a patient. Understanding which factors are most strongly associated with opting out among young underserved racial/ ethnic registered donors compared with their White counterparts will provide the basis for specific interventions to improve donor retention. We sought to determine the key, modifiable psychosocial, registry-related, and donation-related characteristics that are uniquely associated with opting out across 5 key racial/ethnic groups of young HSC donor registry members who had been contacted as a potential match for a patient. This study examines data from a large cross-sectional survey of young (age 18 to 30) registry members shortly after they preliminarily matched a patient (CT-stage) and continued toward or opted out of donation (CT-C and CT-NI), stratified by racial/ethnic group and sex. We assessed psychosocial, registry-related, and donation-related characteristics for all participants. We used chi-squared and F tests to assess differences between racial/ethnic groups. A separate logistic regression analysis for each racial/ethnic group was conducted to quantify adjusted associations between each variable and opting out. Then, we compared these associations across the racial/ethnic groups by evaluating the interaction effect between each variable and racial/ethnic group, with the same outcome (CT-C versus CT-NI) in question. Nine hundred thirty-five participants were surveyed, including 284 White, 165 Hispanic, 191 Black, 192 Asian/Pacific Islander, and 103 Multiracial/multiethnic participants. There were significant differences across racial/ethnic groups in values/goals, religious objections to donation, HSC-related medical mistrust, and parental involvement in donation decisions. Adjusted logistic regression subgroup analyses indicated that ambivalence was strongly associated with opting out across all racial/ethnic groups. Greater focus on intrinsic life goals (e.g., raising a family, becoming a community leader, influencing social values) was associated with opting out in the Multiracial/multiethnic, Hispanic, and Asian/Pacific Islander groups. Healthcare mistrust and insufficient registry contact was a significant factor for Hispanic participants. Protective factors against opting out included remembering joining the registry (Black participants), and parental support for donation decision (Asian/Pacific Islander participants). The performance of each logistic regression model was strong, with area-under-the curve ≥.88, CT-stage outcome classification accuracy ≥89%, and good fit between expected and observed opt-out probabilities. In the analysis across different racial/ethnic groups, the only significant interaction was race/ethnicity by whether more contact with the registry would have changed the decision at CT-stage; this variable was significant only for the Hispanic group. In the within-group analysis for Hispanic participants, the "more registry contact" variable was strongly associated with opting out (odds ratio 5.8, P = .03). Consistent with a growing body of HSC donor research, ambivalence was a key factor associated with opting-out for all racial/ethnic groups. Other key variables were differentially associated with opting-out depending on racial/ethnic group. Our study highlights key variables that registries should focus on as they develop targeted and tailored strategies to enhance commitment and reduce attrition of potential donors.

Opting In and Out: A Qualitative Study Exploring Career Break Experiences of Registered Dietitian Nutritionists

BACKGROUND

Since 2002, an average of 17.5% of registered dietitian nutritionists (RDNs) have reported being out of the paid dietetics workforce, and approximately half of those report intention to return. With the Academy of Nutrition and Dietetics' focus on expanding workforce demand and capacity, understanding why and how dietitians opt in and out of the dietetics workforce may provide insights into how to potentially reduce the number of career breaks or expedite and enhance the reentry process.

OBJECTIVE

To explore the lived experiences and perspectives of dietitians who were taking (with intention to return) or had taken a career break and returned to the paid dietetics' workforce.

DESIGN

A qualitative study with semistructured interviews was conducted.

PARTICIPANTS/SETTING

Participants (n = 22) were recruited through purposive sampling over social media. They were required to be credentialed as RDNs, reside in the United States, and have either previously or currently (with intent to return) taken a break from the dietetics workforce. Interviews were conducted using Zoom videoconferencing technology during September 2021.

DATA ANALYSIS

Data were analyzed using a Coding Reliability Thematic Analysis approach.

RESULTS

The data are summarized in four themes: (1) motivations to leave and return, (2) staying connected with dietetics, (3) preparing to return and returning to the dietetics workforce, and (4) desired resources for career breaks and reentry.

CONCLUSIONS

Understanding the experiences of dietitians who take career breaks may help inform career reentry and help the profession meet the current and future workforce demand.

Disbandment rules that most facilitate the evolution of cooperation

Cooperation is considered a mysterious phenomenon from the perspective of adaptive evolution. However, if an individual can separate from an unsatisfactory group and join another, then this can facilitate positive assortment between cooperative types and promote the evolution of cooperation. What kind of disbandment rule most facilitates the evolution of cooperation? A previous study investigated exogenous disbandment rules and showed that, when games are played between two players, a rule where heterogeneous groups disband facilitates the evolution of cooperation. However, in groups of more than two individuals, a rule strictly requiring homogeneity applied if and only if the expected number of rounds played in a group was greater than some critical value. How large is the critical value? In this study, we make a mathematical analysis using evolutionary game theory. Our results show that the critical number of rounds increases greatly as the group size increases. Consequently, for species with large group sizes, e.g., Homo sapiens, under plausible parameter values, the strict homogeneity rule is unlikely to facilitate the evolution of cooperation. We find instead that a disbandment rule that requires a threshold level of homogeneity outperformed the strict homogeneity rule. Furthermore, we calculate the position of internal equilibria at which cooperators and defectors coexist and show that the initial evolution of cooperation is most encouraged when cooperators are tolerant (intolerant) of defectors if the benefit-to-cost ratio is large (small).

Evolution of spite in an n-player game with an opting-out option

The evolution of altruism and spite is facilitated by positive and negative assortments, respectively. Animals repeatedly meet the same opponents and can choose to keep or terminate the interaction. Previous studies have showed that if the probability that the interaction stops depends on how the pairs are, then a positive assortment can emerge, encouraging the evolution of altruism in dyadic interactions and in interactions involving more than two individuals. In contrast, according to another previous study if the probability that the interaction stops depends on how the pairs are, then a negative assortment can emerge, encouraging the evolution of spite in dyadic interactions. Is the evolution of spite facilitated by interactions involving more than two individuals, in addition to dyadic interactions? The present study shows that the evolution of spite in interactions involving many individuals is possible by studying the repeated n-player game played using spiteful and nonspiteful strategies with opting-out options. These results suggest that spite in large groups may evolve through an opt-out mechanism. It also promotes the investigation about whether there are any examples of spiteful behavior in large groups that have evolved through negative assortment in opt-out options in nature.