Inhibitory control effects in adolescent binge eating and consumption of sugar-sweetened beverages and snacks.

Inhibitory control and sensitivity to reward are relevant to the food choices individuals make frequently. An imbalance of these systems can lead to deficits in decision-making that are relevant to food ingestion. This study evaluated the relationship between dietary behaviors - binge eating and consumption of sweetened beverages and snacks - and behavioral control processes among 198 adolescents, ages 14 to 17. Neurocognitive control processes were assessed with the Iowa Gambling Task (IGT), a generic Go/No-Go task, and a food-specific Go/No-Go task. The food-specific version directly ties the task to food cues that trigger responses, addressing an integral link between cue-habit processes. Diet was assessed with self-administered food frequency and binge eating questionnaires. Latent variable models revealed marked gender differences. Inhibitory problems on the food-specific and generic Go/No-Go tasks were significantly correlated with binge eating only in females, whereas inhibitory problems measured with these tasks were the strongest correlates of sweet snack consumption in males. Higher BMI percentile and sedentary behavior also predicted binge eating in females and sweet snack consumption in males. Inhibitory problems on the generic Go/No-Go, poorer affective decision-making on the IGT, and sedentary behavior were associated with sweetened beverage consumption in males, but not females. The food-specific Go/No-Go was not predictive in models evaluating sweetened beverage consumption, providing some initial discriminant validity for the task, which consisted of sweet/fatty snacks as no-go signals and no sugar-sweetened beverage signals. This work extends research findings, revealing gender differences in inhibitory function relevant to behavioral control. Further, the findings contribute to research implicating the relevance of cues in habitual behaviors and their relationship to snack food consumption in an understudied population of diverse adolescents not receiving treatment for eating disorders.

The Distribution of the Product Explains Normal Theory Mediation Confidence Interval Estimation.

The distribution of the product has several useful applications. One of these applications is its use to form confidence intervals for the indirect effect as the product of 2 regression coefficients. The purpose of this article is to investigate how the moments of the distribution of the product explain normal theory mediation confidence interval coverage and imbalance. Values of the critical ratio for each random variable are used to demonstrate how the moments of the distribution of the product change across values of the critical ratio observed in research studies. Results of the simulation study showed that as skewness in absolute value increases, coverage decreases. And as skewness in absolute value and kurtosis increases, imbalance increases. The difference between testing the significance of the indirect effect using the normal theory versus the asymmetric distribution of the product is further illustrated with a real data example. This article is the first study to show the direct link between the distribution of the product and indirect effect confidence intervals and clarifies the results of previous simulation studies by showing why normal theory confidence intervals for indirect effects are often less accurate than those obtained from the asymmetric distribution of the product or from resampling methods.

Sweetened drink and snacking cues in adolescents: a study using ecological momentary assessment.

The objective of this study was to identify physical, social, and intrapersonal cues that were associated with the consumption of sweetened beverages and sweet and salty snacks among adolescents from lower SES neighborhoods. Students were recruited from high schools with a minimum level of 25% free or reduced cost lunches. Using ecological momentary assessment, participants (N=158) were trained to answer brief questionnaires on handheld PDA devices: (a) each time they ate or drank, (b) when prompted randomly, and (c) once each evening. Data were collected over 7days for each participant. Participants reported their location (e.g., school grounds, home), mood, social environment, activities (e.g., watching TV, texting), cravings, food cues (e.g., saw a snack), and food choices. Results showed that having unhealthy snacks or sweet drinks among adolescents was associated with being at school, being with friends, feeling lonely or bored, craving a drink or snack, and being exposed to food cues. Surprisingly, sweet drink consumption was associated with exercising. Watching TV was associated with consuming sweet snacks but not with salty snacks or sweet drinks. These findings identify important environmental and intrapersonal cues to poor snacking choices that may be applied to interventions designed to disrupt these food-related, cue-behavior linked habits.

Mechanisms of motivational interviewing in health promotion: a Bayesian mediation analysis.

BACKGROUND: Counselor behaviors that mediate the efficacy of motivational interviewing (MI) are not well understood, especially when applied to health behavior promotion. We hypothesized that client change talk mediates the relationship between counselor variables and subsequent client behavior change. METHODS: Purposeful sampling identified individuals from a prospective randomized worksite trial using an MI intervention to promote firefighters' healthy diet and regular exercise that increased dietary intake of fruits and vegetables (n = 21) or did not increase intake of fruits and vegetables (n = 22). MI interactions were coded using the Motivational Interviewing Skill Code (MISC 2.1) to categorize counselor and firefighter verbal utterances. Both Bayesian and frequentist mediation analyses were used to investigate whether client change talk mediated the relationship between counselor skills and behavior change. RESULTS: Counselors' global spirit, empathy, and direction and MI-consistent behavioral counts (e.g., reflections, open questions, affirmations, emphasize control) significantly correlated with firefighters' total client change talk utterances (rs = 0.42, 0.40, 0.30, and 0.61, respectively), which correlated significantly with their fruit and vegetable intake increase (r = 0.33). Both Bayesian and frequentist mediation analyses demonstrated that findings were consistent with hypotheses, such that total client change talk mediated the relationship between counselor's skills--MI-consistent behaviors [Bayesian mediated effect: αß = .06 (.03), 95% CI = .02, .12] and MI spirit [Bayesian mediated effect: αß = .06 (.03), 95% CI = .01, .13]--and increased fruit and vegetable consumption. CONCLUSION: Motivational interviewing is a resource- and time-intensive intervention, and is currently being applied in many arenas. Previous research has identified the importance of counselor behaviors and client change talk in the treatment of substance use disorders. Our results indicate that similar mechanisms may underlie the effects of MI for dietary change. These results inform MI training and application by identifying those processes critical for MI success in health promotion domains.

Parents' Attitudes Toward Domestic Violence as a Risk Factor for Early Childhood Development: Testing an Actor-Partner Interdependence Model Using UNICEF MICS.

Purpose: While the importance of domestic violence has been examined in relation to parenting behaviors and child development, less is known about the link between justifying attitudes toward wife beating and parenting, especially in low- and middle-income countries (LMIC). This study employs an actor-partner interdependence mediation model to examine how parents' justifying attitudes toward violence against women relate to their own (actor effects) and their partners' (partner effects) level of parental involvement, which then influence their preschool children's early development. Method: Using data from mothers, fathers, and children in 16,010 families residing in LMIC that participated in UNICEF's Multiple Indicator Cluster Survey Waves 4-5-6 and a dyadic mediation modeling approach, we have examined the associations between maternal and paternal justification of violence against women, parental involvement, and children's early development. Results: Results revealed that mothers' greater justification of violence against themselves were associated with decreased level of maternal (actor effect) and paternal (partner effect) involvement, while fathers' greater justification of violence against their wives was related to decreased paternal involvement (actor effect). Furthermore, mediation tests indicated that paternal justification of violence was negatively and indirectly associated with early childhood development through paternal involvement. Moreover, maternal justification of violence was negatively and indirectly associated with early childhood development through both maternal and paternal involvement. Conclusion: Mothers' and fathers' justifying attitudes toward domestic violence emerge as a possible risk factor for child development that can be addressed by preventive interventions.

Can school teachers' willingness to teach ASD-inclusion classes be increased via special education training? Uncovering mediating mechanisms.

Changing teacher willingness to teach inclusive classes is critical in achieving optimal outcomes for students with autism spectrum disorder (ASD). The present study investigated the mechanisms underlying the effects of a teacher training in special education strategies for students with ASD on mainstream school teachers' behavioral intentions toward inclusive education. Specifically, the role of attitudes and autism self-efficacy were explored as mediators in this process. The sample comprised 763 mainstream school teachers from eleven cities in Northeastern Turkey who participated in an intensive training that included special education strategies for students with ASD, evidence-based special education applications, and inclusive education practices. Statistical mediation analyses revealed that the training increased teachers' willingness to teach inclusive classes and intention to implement special education techniques in the regular education classroom through increasing their autism self-efficacy. However, though attitudes toward inclusive education was a significant predictor of both willingness to teach inclusive classes and intent to use special education techniques, the training did not improve attitudes. Based on these findings, additional strategies or components to change attitudes toward inclusive education were recommended to be integrated into the teacher training programs on special education strategies for inclusive education.

Does learning to code influence cognitive skills of elementary school children? Findings from a randomized experiment.

BACKGROUND: Coding has been added to school curricula in several countries, being one of the necessary competencies of the 21st century. Although it has also been suggested to foster the development of several cognitive skills such as computational thinking and problem-solving, studies on the effects of coding are very limited, provide mixed results, and lack causal evidence. AIM: This study aims to evaluate the impact of a learn-to-code programme on three cognitive skills in children: computational thinking, fluid intelligence, and spatial orientation, using a randomized trial. SAMPLE: One hundred seventy-four (n = 81 girls) 4th-grade children participated in the study. METHODS: Children were randomly assigned to one of the three 10-week learning programmes: learn-to-code (treatment of interest), mathematics (another STEM-related comparison treatment), and reading (control). Children responded to paper-pencil computational thinking, and spatial orientation measurements, and face-to-face matrix reasoning task at pre- and post-tests. RESULTS: Results showed that children's computational thinking scores increased significantly only in the learn-to-code condition. Fluid intelligence significantly increased in all conditions, possibly due to a practice effect. The spatial orientation did not improve in any of the conditions. CONCLUSION: These findings suggested that learning to code can be selectively beneficial for the development of computational thinking skills while not effective for spatial reasoning and fluid intelligence.

Causal Mediation Analysis in the Presence of Post-treatment Confounding Variables: A Monte Carlo Simulation Study.

In many disciplines, mediating processes are usually investigated with randomized experiments and linear regression to determine if the treatment affects the outcome through a mediator. However, randomizing the treatment will not yield accurate causal direct and indirect estimates unless certain assumptions are satisfied since the mediator status is not randomized. This study describes methods to estimate causal direct and indirect effects and reports the results of a large Monte Carlo simulation study on the performance of the ordinary regression and modern causal mediation analysis methods, including a previously untested doubly robust sequential g-estimation method, when there are confounders of the mediator-to-outcome relation. Results show that failing to measure and incorporate potential post-treatment confounders in a mediation model leads to biased estimates, regardless of the analysis method used. Results emphasize the importance of measuring potential confounding variables and conducting sensitivity analysis.

Statistical power for the comparative regression discontinuity design with a nonequivalent comparison group.

In the "sharp" regression discontinuity design (RD), all units scoring on one side of a designated score on an assignment variable receive treatment, whereas those scoring on the other side become controls. Thus the continuous assignment variable and binary treatment indicator are measured on the same scale. Because each must be in the impact model, the resulting multi-collinearity reduces the efficiency of the RD design. However, untreated comparison data can be added along the assignment variable, and a comparative regression discontinuity design (CRD) is then created. When the untreated data come from a non-equivalent comparison group, we call this CRD-CG. Assuming linear functional forms, we show that power in CRD-CG is (a) greater than in basic RD; (b) less sensitive to the location of the cutoff and the distribution of the assignment variable; and that (c) fewer treated units are needed in the basic RD component within the CRD-CG so that savings can result from having fewer treated cases. The theory we develop is used to make numerical predictions about the efficiency of basic RD and CRD-CG relative to each other and to a randomized control trial. Data from the National Head Start Impact study are used to test these predictions. The obtained estimates are closer to the predicted parameters for CRD-CG than for basic RD and are generally quite close to the parameter predictions, supporting the emerging argument that CRD should be the design of choice in many applications for which basic RD is now used. (PsycINFO Database Record

Comparative Regression Discontinuity: A Stress Test With Small Samples.

Compared to the randomized experiment (RE), the regression discontinuity design (RDD) has three main limitations: (1) In expectation, its results are unbiased only at the treatment cutoff and not for the entire study population; (2) it is less efficient than the RE and so requires more cases for the same statistical power; and (3) it requires correctly specifying the functional form that relates the assignment and outcome variables. One way to overcome these limitations might be to add a no-treatment functional form to the basic RDD and including it in the outcome analysis as a comparison function rather than as a covariate to increase power. Doing this creates a comparative regression discontinuity design (CRD). It has three untreated regression lines. Two are in the untreated segment of the RDD-the usual RDD one and the added untreated comparison function-while the third is in the treated RDD segment. Also observed is the treated regression line in the treated segment. Recent studies comparing RE, RDD, and CRD causal estimates have found that CRD reduces imprecision compared to RDD and also produces valid causal estimates at the treatment cutoff and also along all the rest of the assignment variable. The present study seeks to replicate these results, but with considerably smaller sample sizes. The power difference between RDD and CRD is replicated, but not the bias results either at the treatment cutoff or away from it. We conclude that CRD without large samples can be dangerous.

Bias, Type I Error Rates, and Statistical Power of a Latent Mediation Model in the Presence of Violations of Invariance.

When testing a statistical mediation model, it is assumed that factorial measurement invariance holds for the mediating construct across levels of the independent variable X. The consequences of failing to address the violations of measurement invariance in mediation models are largely unknown. The purpose of the present study was to systematically examine the impact of mediator noninvariance on the Type I error rates, statistical power, and relative bias in parameter estimates of the mediated effect in the single mediator model. The results of a large simulation study indicated that, in general, the mediated effect was robust to violations of invariance in loadings. In contrast, most conditions with violations of intercept invariance exhibited severely positively biased mediated effects, Type I error rates above acceptable levels, and statistical power larger than in the invariant conditions. The implications of these results are discussed and recommendations are offered.

Narcissism and United States' culture: The view from home and around the world.

The issue of Americans' levels of narcissism is subject to lively debate. The focus of the present research is on the perception of national character (PNC) of Americans as a group. In Study 1, American adults (N = 100) rated Americans as significantly more narcissistic than they perceived themselves and acquaintances. In Study 2, this finding was replicated with American college students (N = 322). PNC ratings of personality traits and externalizing behaviors revealed that Americans were perceived as disagreeable and antisocial as well. In Study 3, we examined the broader characteristics associated with PNC ratings (N = 183). Americans rated the typical American as average on a variety of characteristics (e.g., wealth, education, health, likability) and PNC ratings of narcissism were largely unrelated to these ratings. In Study 4 (N = 1,202) Americans rated PNCs for different prespecified groups of Americans; as expected, PNC ratings of narcissism differed by gender, age, and occupational status such that American males, younger Americans, and Americans working in high-visibility and status occupations were seen as more narcissistic. In Study 5 (N = 733), citizens of 4 other world regions (Basque Country, China, England, Turkey) rated members of their own region as more narcissistic than they perceived themselves, but the effect sizes were smaller than those found in the case of Americans' perceptions of Americans. Additionally, members of these other regions rated Americans as more narcissistic than members of their own region. Finally, in Study 6, participants from around the world (N = 377) rated Americans as more narcissistic, extraverted, and antagonistic than members of their own countries. We discuss the role that America's position as a global economic and military power, paired with a culture that creates and reifies celebrity figures, may play in leading to perceptions of Americans as considerably narcissistic.

Sensitivity plots for confounder bias in the single mediator model.

BACKGROUND: Causal inference continues to be a critical aspect of evaluation research. Recent research in causal inference for statistical mediation has focused on addressing the sequential ignorability assumption; specifically, that there is no confounding between the mediator and the outcome variable. OBJECTIVES: This article compares and contrasts three different methods for assessing sensitivity to confounding and describes the graphical depiction of these methods. DESIGN: Two types of data were used to fully examine the plots for sensitivity analysis. The first type was generated data from a single mediator model with a confounder influencing both the mediator and the outcome variable. The second was data from an actual intervention study. With both types of data, situations are examined where confounding has a large effect and a small effect. SUBJECTS: The nonsimulated data were from a large intervention study to decrease intentions to use steroids among high school football players. We demonstrate one situation where confounding is likely and another situation where confounding is unlikely. CONCLUSIONS: We discuss how these methods could be implemented in future mediation studies as well as the limitations and future directions for these methods.

Worksite wellness program implementation: a model of translational effectiveness.

Occupational health promotion programs with documented efficacy have not penetrated worksites. Establishing an implementation model would allow focusing on mediating aspects to enhance installation and use of evidence-based occupational wellness interventions. The purpose of the study was to implement an established wellness program in fire departments and define predictors of program exposure/dose to outcomes to define a cross-sectional model of translational effectiveness. The study is a prospective observational study among 12 NW fire departments. Data were collected before and following installation, and findings were used to conduct mediation analysis and develop a translational effectiveness model. Worker age was examined for its impact. Leadership, scheduling/competing demands, and tailoring were confirmed as model components, while organizational climate was not a factor. The established model fit data well (χ (2)(9) = 25.57, CFI = 0.99, RMSEA = 0.05, SRMR = 0.03). Older firefighters, nearing retirement, appeared to have influences that both enhanced and hindered participation. Findings can inform implementation of worksite wellness in fire departments, and the prioritized influences and translational model can be validated and manipulated in these and other settings to more efficiently move health promotion science to service.

Body mass index as a predictor of firefighter injury and workers' compensation claims.

OBJECTIVE: To determine the relationship between lifestyle variables including body mass index and filing a workers' compensation claim due to firefighter injury. METHODS: A cross-sectional evaluation of firefighter injury related to workers" compensation claims occurring 5 years after the original Promoting Healthy Lifestyles: Alternative Models' Effects study intervention. RESULTS: A logistic regression analysis for variables predicting filing a workers' compensation claim due to an injury was performed with a total of 433 participants. The odds of filing a compensation claim were almost 3 times higher for firefighters with a body mass index of more than 30 kg/m than firefighters with a normal body mass index (odds ratio, 2.89; P < 0.05). CONCLUSIONS: This study addresses a high-priority area of reducing firefighter injuries and workers' compensation claims. Maintaining a healthy body weight is important to reduce injury and workers' compensation claims among firefighters.