Estimation of Controlled Direct Effects in Longitudinal Mediation Analyses with Latent Variables in Randomized Studies

Abstract

In a randomized study with longitudinal data on a mediator and outcome, estimating the direct effect of treatment on the outcome at a particular time requires adjusting for confounding of the association between the outcome and all preceding instances of the mediator. When the confounders are themselves affected by treatment, standard regression adjustment is prone to severe bias. In contrast, G-estimation requires less stringent assumptions than path analysis using SEM to unbiasedly estimate the direct effect even in linear settings. In this article, we propose a G-estimation method to estimate the controlled direct effect of treatment on the outcome, by adapting existing G-estimation methods for time-varying treatments without mediators. The proposed method can accommodate continuous and noncontinuous mediators, and requires no models for the confounders. Unbiased estimation only requires correctly specifying a mean model for either the mediator or the outcome. The method is further extended to settings where the mediator or outcome, or both, are latent, and generalizes existing methods for single measurement occasions of the mediator and outcome to longitudinal data on the mediator and outcome. The methods are utilized to assess the effects of an intervention on physical activity that is possibly mediated by motivation to exercise in a randomized study.     

Envisioning more virtuous virtues

ABSTRACT

This response addresses three key themes related to the interdisciplinary study of virtue: limitations of self-reports, demoting of the virtues, and concerns about cultural issues. I suggest that self-regulation theories of how people develop virtues are needed in order to understand how virtues (even just two at a time) may work in tandem to influence behavior. I suggest that psychologists and philosophers approach an interdisciplinary conversation about virtue with an eye towards the limitations in our field’s typical way of approaching constructs. Such an approach provides an opportunity to see problems that are typically masked by disciplinary habits.     

Positive psychology,the classification of character strengths and virtues,and issues of measurement

ABSTRACT

This essay raises concerns about positive psychology’s classification of character strengths and virtues and issues of measurement. Part I examines the process whereby the classification was compiled. Part II turns to issues of measurement and questions about positive psychologists’ sensitivity to variations in the meanings of the constructs they purport to measure, both within and across cultures. I argue that attempts to find a ‘deep structure’ of the character strengths and virtues should proceed hand in hand with efforts to render positive psychology and its measurement tools more sensitive to variability in character strengths and virtues across and within cultures. The essay concludes with suggestions for future research.     

Utrecht Gender Dysphoria Scale - Gender Spectrum (UGDS-GS): Construct validity among transgender,nonbinary, and LGBQ samples

Abstract

Background: Researchers combined both versions of the original Utrecht Gender Dysphoria Scale (UGDS) to create a single gender spectrum version (UGDS-GS) which measures dissatisfaction with gender identity and expression over time as well as comfort with affirmed gender identity.

Aim: This study examined the construct validity of the newly revised, UGDS-GS.

Method: Tests of measurement invariance were conducted in stages to assess measurement invariance of the UGDS-GS across three groups: cisgender, binary transgender, and nonbinary/genderqueer.

Results: Findings indicate that the UGDS-GS functions acceptably in all three gender groups (configural and metric invariance). Also, across binary transgender and nonbinary/genderqueer groups, the measure functions very similarly with all four types of invariance. Item level findings highlight the specificity of the measure to distinguish experiences of binary transgender and nonbinary/genderqueer persons differently from cisgender LGBQ individuals.

Conclusions: The UGDS-GS demonstrates a large degree of invariance across binary transgender, nonbinary/genderqueer, and cisgender LGBQ subgroups; and therefore, findings indicate this revision to be a substantial improvement. This 18-item self-report, Likert-type scale measure is a) inclusive of all gender identities and expressions (e.g., transfeminine spectrum, transmasculine spectrum, genderqueer, nonbinary, cisgender); b) appropriate for use longitudinally from adolescence to adulthood; and c) administered at any point in the social or medical transition process, if applicable, or in community-based research focused on gender dysphoria that examines cisgender and transgender persons.     

Testing Differential Item Functioning in Small Samples

Abstract

Differential item functioning (DIF) is a pernicious statistical issue that can mask true group differences on a target latent construct. A considerable amount of research has focused on evaluating methods for testing DIF, such as using likelihood ratio tests in item response theory (IRT). Most of this research has focused on the asymptotic properties of DIF testing, in part because many latent variable methods require large samples to obtain stable parameter estimates. Much less research has evaluated these methods in small sample sizes despite the fact that many social and behavioral scientists frequently encounter small samples in practice. In this article, we examine the extent to which model complexity—the number of model parameters estimated simultaneously—affects the recovery of DIF in small samples. We compare three models that vary in complexity: logistic regression with sum scores, the 1-parameter logistic IRT model, and the 2-parameter logistic IRT model. We expected that logistic regression with sum scores and the 1-parameter logistic IRT model would more accurately estimate DIF because these models yielded more stable estimates despite being misspecified. Indeed, a simulation study and empirical example of adolescent substance use show that, even when data are generated from / assumed to be a 2-parameter logistic IRT, using parsimonious models in small samples leads to more powerful tests of DIF while adequately controlling for Type I error. We also provide evidence for minimum sample sizes needed to detect DIF, and we evaluate whether applying corrections for multiple testing is advisable. Finally, we provide recommendations for applied researchers who conduct DIF analyses in small samples.     

Replies to comments on "Which method delivers greater signal-to-noise ratio: Structural equation modelling or regression analysis with weighted composites?" by Yuan and Fang (2023)

Observational data typically contain measurement errors. Covariance-based structural equation modelling (CB-SEM) is capable of modelling measurement errors and yields consistent parameter estimates. In contrast, methods of regression analysis using weighted composites as well as a partial least squares approach to SEM facilitate the prediction and diagnosis of individuals/participants. But regression analysis with weighted composites has been known to yield attenuated regression coefficients when predictors contain errors. Contrary to the common belief that CB-SEM is the preferred method for the analysis of observational data, this article shows that regression analysis via weighted composites yields parameter estimates with much smaller standard errors, and thus corresponds to greater values of the signal-to-noise ratio (SNR). In particular, the SNR for the regression coefficient via the least squares (LS) method with equally weighted composites is mathematically greater than that by CB-SEM if the items for each factor are parallel, even when the SEM model is correctly specified and estimated by an efficient method. Analytical, numerical and empirical results also show that LS regression using weighted composites performs as well as or better than the normal maximum likelihood method for CB-SEM under many conditions even when the population distribution is multivariate normal. Results also show that the LS regression coefficients become more efficient when considering the sampling errors in the weights of composites than those that are conditional on weights.     

Development and validation of a measure for emotion regulation at work: Introducing the Workplace Emotion Regulation Preference Inventory (WERPI)

Emotion regulation preference varies from person to person. However, the emotion regulation literature has mostly dichotomized preference to cognitive change and response modulation. The current investigation focused on development and validation of a comprehensive measure of workplace emotion regulation and examined the relationship between all emotion regulation strategies using a well-known taxonomy (Gross, 1998) and customer service performance. Preliminary evidence supports the validity of the new measure. The four groups identified in this analysis showed significant differences on customer service performance, suggesting that individual differences in regulation preference may be important to consider. Theoretical and practical implications of findings are discussed.     

大学生主观幸福感的测量研究

本文主要论述了大学生主观幸福感的测量研究的现状及其测量研究的内容,并讨论了大学生主观幸福感的测量研究的发展趋向,旨在为以后的研究提供参考。     

Staying and Returning dynamics of young children's attention

In this paper, we decompose selective sustained attending behavior into components of continuous attention maintenance and attentional transitions and study how each of these components develops in young children. Our results in two experiments suggest that changes in children's ability to return attention to a target locus after distraction (“Returning”) play a crucial role in the development of selective sustained attention between the ages of 3.5–6 years, perhaps to a greater extent than changes in the ability to continuously maintain attention on the target (“Staying”). We further distinguish Returning from the behavior of transitioning attention away from task (i.e., becoming distracted) and investigate the relative contributions of bottom-up and top-down factors on these different types of attentional transitions. Overall, these results (a) suggest the importance of understanding the cognitive process of transitioning attention for understanding selective sustained attention and its development, (b) provide an empirical paradigm within which to study this process, and (c) begin to characterize basic features of this process, namely its development and its relative dependence on top-down and bottom-up influences on attention.

Research Highlights

• Young children exhibited an endogenously ability, Returning, to preferentially transition attention to task-relevant information over task-irrelevant information.
• Selective sustained attention and its development were decomposed into Returning and Staying, or task-selective attention maintenance, using novel eye-tracking-based measures.
• Returning improved between the ages of 3.5–6 years, to a greater extent than Staying.
• Improvements in Returning supported improvements in selective sustained attention between these ages.

     

“To work,or not to work,that is the question” – Recent trends and avenues for research on presenteeism

ABSTRACT

This position paper brings together recent and emerging developments in the field of presenteeism. A critical synthesis of the evidence is needed due to persisting conceptual and methodological challenges as well as the increased volume of research in the field. This paper integrates emerging evidence and critical thinking into three areas: (1) concept, (2) measurement and methodological issues, and (3) the context of presenteeism. First, due to the variety of existing definitions, competing understandings, as well as the notion of positive presenteeism, it is important to reconsider the notion of presenteeism. Second, it is important to reflect on the measurement of the act of presenteeism and the productivity loss associated with that. Third, following the call to investigate presenteeism in specific contexts, it is important to explain the social, occupational, cross-cultural aspects, as well as the contemporary workplace changes. Based on this critical synthesis, we conclude by identifying recommendations for future research on presenteeism.