Using independent covariates in experimental designs: Quantifying the trade-off between power boost and Type I error inflation

Reimagine Aging: A Process-Based Intervention to Decrease Internalized Ageism

OBJECTIVES

Exposure to ageism may be internalized in older adults, and this can have severe consequences. However, little research has addressed reducing internalized ageism. Thus, Reimagine Aging, a 6-week process-based intervention to reduce internalized ageism, was designed and implemented, using education, acceptance and commitment therapy, and attributional retraining to target theoretically based mechanisms of change.

METHODS

Seventy-two older adults (M = 70.4 years, SD = 6.4 years) participated in Reimagine Aging, consented to participate in this robust single-sample pilot study, and provided valid data. Participants completed questionnaires prior to, immediately following, and 2 months after the intervention.

RESULTS

Participants' self-perceptions of aging (η p 2 =0.37, p < .001) and perceptions of older adults (η p 2 =0.27, p < .001) became significantly more positive, associated with large effect sizes. Furthermore, these positive gains were mediated by increases in psychological flexibility, mindfulness, and perceived control.

DISCUSSION

This study provides initial support for this process-based intervention targeting a reduction of internalized ageism.

CLINICAL IMPLICATIONS

This program has the potential to reduce the negative impact internalized ageism has on the health of older adults. Furthermore, it provides novel insights into intervention targets and tools that may be useful in achieving this reduction.

Political news on Instagram: influencer versus traditional magazine and the role of their expertise in consumers' credibility perceptions and news engagement

Introduction

Social networking sites (SNS) are increasingly used by consumers to read and share political news. In this context, Instagram plays an important role due to its prevalence and visual characteristics. However, previous research has highlighted that consumers fail to identify the source of online news, though source characteristics were shown to be vital for news credibility perceptions. Nevertheless, research on whether and which source characteristics have an influence on Instagram consumers' credibility perceptions and news engagement intentions are lacking. The present study addresses this empirical gap by investigating potential effects of source expertise and source type on source credibility, message credibility, news engagement intentions, and personal involvement regarding political news on Instagram.

Method

We randomly presented participants with political news posts from one of four sources, either the Instagram representation of a fictional news magazine or influencer with or without political expertise. Participants assessed the perceived credibility of the source and the news, their news engagement intentions, and personal involvement.

Results

We analyzed data from 416 participants. Results showed significant main effects of source expertise on each of the dependent variables. Those were shown to be indirect effects through personal involvement. There were hardly any effects of source type.

Discussion

These results provide new insights into the role of source expertise on credibility perceptions and news engagement intentions, and provide insights into the comparison between influencers and Instagram representations of traditional news magazines. Theoretical implications for future research and practical implications for content creators, users, and SNS platforms are discussed.

Internalized Homophobia and Suicide Ideation Among Sexual Minority Adults: The Serial Mediation of Core Self-Evaluations and Depression

Internalized homophobia (IH) is the endorsement of negative attitudes and stereotypes about sexual minority individuals among those who are LGBQ + . However, although IH is associated with suicide ideation, the underlying mechanisms of this association are relatively understudied. To address this limitation, this research investigates Core Self-Evaluation (CSE; one's fundamental evaluations about themselves, their own abilities, and their own control) and depression as underlying mechanisms associating IH with suicide ideation. CSE comprises four traits: self-esteem, locus of control, emotional stability, and generalized self-efficacy. An online survey was completed by 404 sexual minority adults (Mean_age = 27.42 years, %Female = 51.50, %Male = 30.40, %Trans Female = 3.2, %Trans Male = 5.4). Participants were recruited via Prolific, an online crowdsourcing platform. Four serial mediation analyses examined the direct and indirect effects of IH on suicide ideation via each CSE trait and depression symptoms. Results showed support for the CSE-depression mediated pathway. Self-esteem, emotional stability, and general self-efficacy (but not locus of control) mediated the relationship between IH and suicide ideation via depression symptoms. Across three serial mediations, greater IH was associated with lower (1) self-esteem, (2) emotional stability, and (3) self-efficacy; lower self-esteem, emotional stability, and self-efficacy were associated with greater reported depression symptoms, which were then associated with greater suicide ideation. This research has implications for understanding the underlying mechanisms that associate IH with poor mental health among sexual minority adults. Studying the social and psychological mechanisms can help develop therapeutic interventions that target suicide ideation and promote positive self-evaluations among sexual minority individuals.

Who benefits from individual placement and support? A meta-analysis

AIMS

Individual placement and support (IPS) is an evidence-based service model to support people with mental disorders in obtaining and sustaining competitive employment. IPS is increasingly offered to a broad variety of service users. In this meta-analysis we analysed the relative effectiveness of IPS for different subgroups of service users both based on the diagnosis and defined by a range of clinical, functional and personal characteristics.

METHODS

We included randomised controlled trials that evaluated IPS for service users diagnosed with any mental disorder. We examined effect sizes for the between-group differences at follow-up for three outcome measures (employment rate, job duration and wages), controlling for methodological confounders (type of control group, follow-up duration and geographic region). Using sensitivity analyses of subgroup differences, we analysed moderating effects of the following diagnostic, clinical, functional and personal characteristics: severe mental illness (SMI), common mental disorders (CMD), schizophrenia spectrum disorders, mood disorders, duration of illness, the severity of symptoms, level of functioning, age, comorbid alcohol and substance use, education level and employment history.

RESULTS

IPS is effective in improving employment outcomes compared to the control group in all subgroups, regardless of any methodological confounder. However, IPS was relatively more effective for service users with SMIs, schizophrenia spectrum disorders and a low symptom severity. Although IPS was still effective for people with CMD and with major depressive disorder, it was relatively less effective for these subgroups. IPS was equally effective after both a short and a long follow-up period. However, we found small, but clinically not meaningful, differences in effectiveness of IPS between active and passive control groups. Finally, IPS was relatively less effective in European studies compared to non-European studies, which could be explained by a potential benefits trap in high welfare countries.

CONCLUSIONS

IPS is effective for all different subgroups, regardless of diagnostic, clinical, functional and personal characteristics. However, there might be a risk of false-positive subgroup outcomes and results should be handled with caution. Future research should focus on whether, and if so, how the IPS model should be adapted to better meet the vocational needs of people with CMD and higher symptom severity.

Moral dilemmas and trust in leaders during a global health crisis

Trust in leaders is central to citizen compliance with public policies. One potential determinant of trust is how leaders resolve conflicts between utilitarian and non-utilitarian ethical principles in moral dilemmas. Past research suggests that utilitarian responses to dilemmas can both erode and enhance trust in leaders: sacrificing some people to save many others ('instrumental harm') reduces trust, while maximizing the welfare of everyone equally ('impartial beneficence') may increase trust. In a multi-site experiment spanning 22 countries on six continents, participants (N = 23,929) completed self-report (N = 17,591) and behavioural (N = 12,638) measures of trust in leaders who endorsed utilitarian or non-utilitarian principles in dilemmas concerning the COVID-19 pandemic. Across both the self-report and behavioural measures, endorsement of instrumental harm decreased trust, while endorsement of impartial beneficence increased trust. These results show how support for different ethical principles can impact trust in leaders, and inform effective public communication during times of global crisis. PROTOCOL REGISTRATION STATEMENT: The Stage 1 protocol for this Registered Report was accepted in principle on 13 November 2020. The protocol, as accepted by the journal, can be found at https://doi.org/10.6084/m9.figshare.13247315.v1 .

Power Analysis for Parameter Estimation in Structural Equation Modeling: A Discussion and Tutorial

Despite the widespread and rising popularity of structural equation modeling (SEM) in psychology, there is still much confusion surrounding how to choose an appropriate sample size for SEM. Currently available guidance primarily consists of sample-size rules of thumb that are not backed up by research and power analyses for detecting model misspecification. Missing from most current practices is power analysis for detecting a target effect (e.g., a regression coefficient between latent variables). In this article, we (a) distinguish power to detect model misspecification from power to detect a target effect, (b) report the results of a simulation study on power to detect a target regression coefficient in a three-predictor latent regression model, and (c) introduce a user-friendly Shiny app, pwrSEM, for conducting power analysis for detecting target effects in structural equation models.

What is the optimum design for my animal experiment?

Within preclinical research, attention has focused on experimental design and how current practices can lead to poor reproducibility. There are numerous decision points when designing experiments. Ethically, when working with animals we need to conduct a harm-benefit analysis to ensure the animal use is justified for the scientific gain. Experiments should be robust, not use more or fewer animals than necessary, and truly add to the knowledge base of science. Using case studies to explore these decision points, we consider how individual experiments can be designed in several different ways. We use the Experimental Design Assistant (EDA) graphical summary of each experiment to visualise the design differences and then consider the strengths and weaknesses of each design. Through this format, we explore key and topical experimental design issues such as pseudo-replication, blocking, covariates, sex bias, inference space, standardisation fallacy and factorial designs. There are numerous articles discussing these critical issues in the literature, but here we bring together these topics and explore them using real-world examples allowing the implications of the choice of design to be considered. Fundamentally, there is no perfect experiment; choices must be made which will have an impact on the conclusions that can be drawn. We need to understand the limitations of an experiment's design and when we report the experiments, we need to share the caveats that inherently exist.

Skin tone, life satisfaction, and psychological distress among African Americans: The mediating effect of stigma consciousness

This study examined the indirect effect of skin tone on psychological distress via (1) stigma consciousness and (2) life satisfaction among African American adults (N = 780; %Female = 57.65%; M_age = 37.68). Results show indirect effects of (1) skin tone on life satisfaction and (2) skin tone on psychological distress, each via stigma consciousness. Specifically, those with darker (vs. lighter) skin tones reported increased stigma consciousness, which then predicted (1) lower life satisfaction and (2) lower levels of psychological distress. Life satisfaction did not predict psychological distress. Implications for African American mental health are discussed.

Self- and group-focused internalized racism, anxiety, and depression symptoms among African American adults: A core self-evaluation mediated pathway

Internalized racism (IR) is a form of racism that leads people to internalize stereotypes about their racial/ethnic group (i.e., group-focused IR) and/or about themselves because of their racial/ethnic group membership (i.e., self-focused IR). However, although IR is associated with poor mental health, little is known about the underlying mechanisms of these associations. To address this limitation, this research investigates the core self-evaluation (CSE; a person’s fundamental evaluations about themselves, their own abilities, and their own control) mediated pathway as one potential pathway. CSE consists of four traits: self-esteem (SE), locus of control (LoC), emotional stability (ES), and generalized self-efficacy (GSE). With a sample of 780 Black/African American adults ( Mage = 37.68 years, % Female = 57.6), this study investigated the independent direct and indirect effects of group- and self-focused IR on depression and anxiety symptoms via CSE using structural equation modeling. Confirming predictions, self- and group-focused IR predicted greater anxiety and depression symptoms and lower SE and ES. However, against predictions, both forms of IR were associated with increased internal LoC and were not associated with GSE. Last, results show partial support for the CSE mediated pathway, such that SE and ES (but not LoC or GSE) mediated the relationship between both self- and group-focused IR and anxiety and depression symptoms. Results suggest that IR is indirectly related to mental health via the more affective (SE, ES) relative to motivational (LoC, GSE) components of CSE, which has implications for understanding underlying mechanisms associating IR with poor mental health among racial/ethnic minorities.

Frontal asymmetry: A novel biomarker for physical activity and sedentary behavior

Past research has demonstrated that regular physical activity provides a myriad of physical, mental, and emotional benefits. The decision of whether to partake in physical activity (PA) or remain sedentary appears to be partially influenced by motivational and emotional systems. Research suggests left frontal alpha asymmetry is a neural marker of approach motivation. However, studies have not explored whether habitual levels of PA and sedentary behavior relate to this neurophysiological signal. Across two studies, individuals completed measures of habitual PA and sedentary behavior using the International Physical Activity Questionnaire-Short Form. Then, resting electroencephalography activity was recorded. Results of Study 1 (N = 32, 72% women) indicated that more time spent sitting on both weekdays and weekend days were associated with less left frontal asymmetry (r = -.45, p = .027, and r = -.55, p = .005, respectively). Study 2 recruited a larger sample (N = 96, 31% women) and investigated moderators. Greater levels of moderate (r = .27) and total (r = .29) PA were associated with greater left frontal asymmetry (ps < .05), and the relationship between sedentary behavior and less left frontal asymmetry was moderated by sex (weekday: β = .62, p = .011; weekend day: β = .41, p = .034). Our results suggest that left frontal asymmetry may be a novel neurophysiological marker for PA and sedentary behavior.

When good for business is not good enough: Effects of pro-diversity beliefs and instrumentality of diversity on intergroup attitudes

Instrumentality-based pro-diversity beliefs (i.e., beliefs that diverse groups outperform homogenous groups in terms of group functioning) have been shown to improve intergroup attitudes. However, such valuing of diversity due to its expected instrumentality holds the risk that outgroups may be devalued in situations when diversity ends up being detrimental to group functioning. Across four experiments, we studied the interplay between instrumentality-based pro-diversity beliefs, actual instrumentality of ethnic diversity, and outgroup attitudes. Our results do not reveal a robust interaction effect between instrumentality-based pro-diversity beliefs and actual instrumentality of diverse groups. Some evidence, however, supports the assumption that instrumentality-based pro-diversity beliefs yielded a weaker positive or even a negative effect on ethnic outgroup attitudes when ethnic diversity was perceived as non-instrumental (i.e., when diversity was perceived as having a negative impact on group functioning). Theoretical contributions, practical implications, and directions for future research are discussed.

Losses tune differently than gains: how gains and losses shape attentional scope and influence goal pursuit

Research on the asymmetric effect of negative versus positive affective states (induced by gains or losses) on scope of attention, both at a perceptual and a conceptual level, is abundant. However, little is known about the moderating effect of anticipating gains or losses versus actually experiencing them and about any downstream consequences of these effects on goal-directed behaviour. In two studies, we show that gains versus losses induce qualitatively different processes. In Experiment 1, we demonstrate that the anticipation of monetary gains results in a narrowing of attentional scope, while experiencing gains broadens the scope of attention. We find the reverse pattern concerning monetary losses - while anticipation of monetary losses results in broadening of attentional scope, the actual experience of losses results in narrowing of attentional scope. Additionally, Experiment 2 replicates these findings and shows how differential attentional tuning as a function of the anticipation versus experience of gains versus losses modulates priming-induced goal-directed behaviour.

Calibrate your confidence in research findings: A tutorial on improving research methods and practices

This article provides an accessible tutorial with concrete guidance for how to start improving research methods and practices in your lab. Following recent calls to improve research methods and practices within and beyond the borders of psychological science, resources have proliferated across book chapters, journal articles, and online media. Many researchers are interested in learning more about cutting-edge methods and practices but are unsure where to begin. In this tutorial, we describe specific tools that help researchers calibrate their confidence in a given set of findings. In Part I, we describe strategies for assessing the likely statistical power of a study, including when and how to conduct different types of power calculations, how to estimate effect sizes, and how to think about power for detecting interactions. In Part II, we provide strategies for assessing the likely type I error rate of a study, including distinguishing clearly between data-independent (“confirmatory”) and data-dependent (“exploratory”) analyses and thinking carefully about different forms and functions of preregistration.

Improving Psychological Science through Transparency and Openness: An Overview

The ability to independently verify and replicate observations made by other researchers is a hallmark of science. In this article, we provide an overview of recent discussions concerning replicability and best practices in mainstream psychology with an emphasis on the practical benefists to both researchers and the field as a whole. We first review challenges individual researchers face in producing research that is both publishable and reliable. We then suggest methods for producing more accurate research claims, such as transparently disclosing how results were obtained and analyzed, preregistering analysis plans, and publicly posting original data and materials. We also discuss ongoing changes at the institutional level to incentivize stronger research. These include officially recognizing open science practices at the journal level, disconnecting the publication decision from the results of a study, training students to conduct replications, and publishing replications. We conclude that these open science practices afford exciting low-cost opportunities to improve the quality of psychological science.

Between-litter variation in developmental studies of hormones and behavior: Inflated false positives and diminished power

Developmental studies of hormones and behavior often include littermates-rodent siblings that share early-life experiences and genes. Due to between-litter variation (i.e., litter effects), the statistical assumption of independent observations is untenable. In two literatures-natural variation in maternal care and prenatal stress-entire litters are categorized based on maternal behavior or experimental condition. Here, we (1) review both literatures; (2) simulate false positive rates for commonly used statistical methods in each literature; and (3) characterize small sample performance of multilevel models (MLM) and generalized estimating equations (GEE). We found that the assumption of independence was routinely violated (>85%), false positives (α=0.05) exceeded nominal levels (up to 0.70), and power (1-β) rarely surpassed 0.80 (even for optimistic sample and effect sizes). Additionally, we show that MLMs and GEEs have adequate performance for common research designs. We discuss implications for the extant literature, the field of behavioral neuroendocrinology, and provide recommendations.