Modeling (in)congruence between dependent variables: The directional and nondirectional difference (DNDD) framework.

This article proposes a new approach to modeling the antecedents of incongruence between 2 dependent variables. In this approach, incongruence is decomposed into 2 orthogonal components representing directional and nondirectional difference (DNDD). Nondirectional difference is further divided into components representing shared and unique variability. We review previous approaches to modeling antecedents of difference, including the use of arithmetic, absolute, and squared differences, as well as the approaches of Edwards (1995) and Cheung (2009). Based on 2 studies, we demonstrate the advantages of DNDD approach compared with other methods. In the first study, we use a Monte Carlo simulation to demonstrate the circumstances under which each type of difference arises, and we compare the insights revealed by each approach. In the second study, we provide an illustrative example of DNDD approach using a field dataset. In the discussion, we review the strengths and limitations of our approach and propose several practical applications. Our article proposes 2 extensions to the basic DNDD approach, including modeling difference with a known target or "true" value, and using multilevel analysis to model nondirectional difference with exchangeable ratings. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

A systematic review and meta-analysis of antecedents of blood donation behavior and intentions.

This meta-analysis sought to identify the strongest antecedents of blood donation behavior and intentions. It synthesized the results of 24 predictive correlational studies of donation behavior and 37 studies of donation intentions. The antecedents were grouped into six research programs: (1) the Theory of Planned Behavior (TPB) and its extensions, (2) prosocial motivation, (3) affective expectations, (4) donor site experience, (5) past donation behavior, and (6) donor demographics. Antecedent categories were cross-validated by multiple coders, and combined effect sizes were analyzed using a random-effects model. For donation behavior, medium positive associations were found with five of the constructs from the extended TPB: intentions to donate, perceived behavioral control, attitude toward donation, self-efficacy and donor role identity. Other antecedents displaying a positive association with donation behavior included anticipated regret for not donating, number of past donations and donor age. Donor experiences at the collection site in the form of temporary deferral or adverse reactions had a medium negative association with behavior. For donation intentions, strong positive associations were observed for perceived behavioral control, attitude, self-efficacy, role identity and anticipated regret. Medium positive associations were observed for personal moral norm, subjective norm, satisfaction, and service quality. All other potential antecedents had weak or non-significant associations with behavior and intentions. Several of these associations were moderated by between-study differences, including donor experience, the period of data collection in which donation behavior was observed, and the use of a nominal (yes/no return) versus a ratio measure of donation behavior. Collectively, the results underscore the importance of enhancing donors' attitudes towards donation and building their perceived behavioral control and self-efficacy to donate. Further, minimizing the risk of adverse reactions and enacting re-recruitment policies for temporarily deferred donors will help protect future donation behavior. Implications of these findings for blood collection agencies and researchers are discussed.

Perceived deterrents to being a plasmapheresis donor in a voluntary, nonremunerated environment.

BACKGROUND: As demand for plasma-derived products increases internationally, maintaining a committed plasmapheresis panel membership is critical for blood collection agencies. This study addresses the current lack of knowledge regarding deterrents to the recruitment and retention of plasmapheresis donors in a voluntary nonremunerated environment. STUDY DESIGN AND METHODS: Nine focus groups (n = 84) and six individual interviews were conducted using semistructured schedules. Three focus groups were conducted with each category of eligible whole blood (WB) donors: those who had 1) declined to convert to plasmapheresis (DTC), 2) converted but lapsed to WB (LWB), and 3) converted and lapsed from the panel completely (LFP). Transcript analysis revealed distinct deterrent categories. RESULTS: The time required for plasmapheresis was a universally identified deterrent, with concerns of donation frequency expectations shared between DTC and LWB. LWB and LFP both reported excessive questioning and paperwork, and eligibility requirements as deterrents. Unique deterrents for DTC were a lack of accurate knowledge about safety and process. LWB reported concerns about plasmapheresis donation outcomes; however, they were more committed to continuing donation than LFP, who reported donation not being salient, being too busy, and poorer donation experiences. CONCLUSION: Providing information to address safety and health concerns should be the focus for successful conversion to plasmapheresis. Setting donation frequency expectations at levels to which donors are accustomed may improve evaluations of the cost/benefit ratio of conversion and retention. Involvement levels (i.e., importance, personal meaning of donation) may be the key differentiator between those donors who return to WB and those that lapse altogether.

Predicting the retention of first-time donors using an extended Theory of Planned Behavior.

BACKGROUND: Donor retention is vital to blood collection agencies. Past research has highlighted the importance of early career behavior for long-term donor retention, yet research investigating the determinants of early donor behavior is scarce. Using an extended Theory of Planned Behavior (TPB), this study sought to identify the predictors of first-time blood donors' early career retention. STUDY DESIGN AND METHODS: First-time donors (n=256) completed three surveys on blood donation. The standard TPB predictors and self-identity as a donor were assessed 3 weeks (Time 1) and at 4 months (Time 2) after an initial donation. Path analyses examined the utility of the extended TPB to predict redonation at 4 and 8 months after initial donation. RESULTS: The extended TPB provided a good fit to the data. Post-Time 1 and 2 behavior was consistently predicted by intention to redonate. Further, intention was predicted by attitudes, perceived control, and self-identity (Times 1 and 2). Donors' intentions to redonate at Time 1 were the strongest predictor of intention to donate at Time 2, while donors' behavior at Time 1 strengthened self-identity as a blood donor at Time 2. CONCLUSION: An extended TPB framework proved efficacious in revealing the determinants of first-time donor retention in an initial 8-month period. The results suggest that collection agencies should intervene to bolster donors' attitudes, perceived control, and identity as a donor during this crucial post-first donation period.

Donating blood: a meta-analytic review of self-reported motivators and deterrents.

Although research on blood donor motivation abounds, most studies have typically focused on small sets of variables, used different terminology to label equivalent constructs, and have not attempted to generalize findings beyond their individual settings. The current study sought to synthesize past findings into a unified taxonomy of blood donation drivers and deterrents and to estimate the prevalence of each factor across the worldwide population of donors and eligible nondonors. Primary studies were collected, and cross-validated categories of donation motivators and deterrents were developed. Proportions of first-time, repeat, lapsed, apheresis, and eligible nondonors endorsing each category were calculated. In terms of motivators, first-time and repeat donors most frequently cited convenience, prosocial motivation, and personal values; apheresis donors similarly cited the latter 2 motivators and money. Conversely, lapsed donors more often cited collection agency reputation, perceived need for donation, and marketing communication as motivators. In terms of deterrents, both donors and nondonors most frequently referred to low self-efficacy to donate, low involvement, inconvenience, absence of marketing communication, ineffective incentives, lack of knowledge about donating, negative service experiences, and fear. The integration of past findings has yielded a comprehensive taxonomy of factors influencing blood donation and has provided insight into the prevalence of each factor across multiple stages of donors' careers. Implications for collection agencies are discussed.