Mediation analysis with structural equation models: Combining theory,design, and statistics

Statistical tests of indirect effects can hardly distinguish between genuine and spurious mediation effects. The present research demonstrates, however, that mediation analysis can be improved by combining a significance test of the indirect effect with assessing the fit of causal models. Testing only the indirect effect can be misleading, because significant results may also be obtained when the underlying causal model is different from the mediation model. We use simulated data to demonstrate that additionally assessing the fit of causal models with structural equation models can be used to exclude subsets of models that are incompatible with the observed data. The results suggest that combining structural equation modeling with appropriate research design and theoretically stringent mediation analysis can improve scientific insights. Finally, we discuss limitations of the structural equation modeling approach, and we emphasize the importance of non‐statistical methods for scientific discovery.     

The power of prospection: mental contrasting and behavior change

People often immerse themselves in dreams and fantasies about a desired future. Though such future fantasies are pleasant, they do not necessarily lead to the effort required to attain the desired future. Indeed, the more positively people fantasize about their desired futures, the less effort they invest and the less successful they are in realizing these futures. However, when fantasies about a desired future are complemented with a clear sense of reality, people find the direction and energy needed to realize their fantasies. We review Fantasy Realization Theory, which explicates these ideas and led to the discovery of mental contrasting future and reality, a self‐regulation strategy of behavior change. Mental contrasting helps people figure out what they really want and wisely select, commit to, and actively pursue prioritized wishes while constructively dealing with setbacks. It helps them live a rewarding life through work, play, health, and relationships.     

Anomalies in the detection of change: When changes in sample size are mistaken for changes in proportions

Detecting changes, in performance, sales, markets, risks, social relations, or public opinions, constitutes an important adaptive function. In a sequential paradigm devised to investigate detection of change, every trial provides a sample of binary outcomes (e.g., correct vs. incorrect student responses). Participants have to decide whether the proportion of a focal feature (e.g., correct responses) in the population from which the sample is drawn has decreased, remained constant, or increased. Strong and persistent anomalies in change detection arise when changes in proportional quantities vary orthogonally to changes in absolute sample size. Proportional increases are readily detected and nonchanges are erroneously perceived as increases when absolute sample size increases. Conversely, decreasing sample size facilitates the correct detection of proportional decreases and the erroneous perception of nonchanges as decreases. These anomalies are however confined to experienced samples of elementary raw events from which proportions have to be inferred inductively. They disappear when sample proportions are described as percentages in a normalized probability format. To explain these challenging findings, it is essential to understand the inductive-learning constraints imposed on decisions from experience.     

Psychological predictors for health-related quality of life and disability in persons with chronic obstructive pulmonary disease (COPD)

Objective: Individuals with chronic obstructive pulmonary disease (COPD) exhibit low physical and mental health-related quality of life (HRQL) and high susceptibility to disability. We investigated the influence of psychological factors on HRQL and disability in COPD individuals recruited from the general population. In line with Leventhal’s common sense model, we expected psychological factors to be associated with HRQL and disability even after controlling for medical status.

Methods: Individuals with COPD (n = 502; 59.7 years old; GOLD grades were I: 3%, II: 17%, III: 34%, IV: 46%) were assessed through an online survey administered via COPD patient organisations in Germany. Individuals filled in the Short Form Health Survey (SF-12), COPD Assessment Test, Patient Health Questionnaire (modules: GAD-2, PHQ-15, PHQ-9), Brief Illness Perception Questionnaire, a questionnaire that assesses causal illness attributions, and the internal illness-related locus of control scale of the ‘KKG questionnaire for the assessment of control beliefs about illness and health’. Multiple linear regressions were calculated.

Results: The investigated factors explained high variances (disability = 56%, physical HRQL = 28%, mental HRQL = 63%, p ≤ .001). Better mental health, more optimistic illness perceptions, attribution to psychological causes, and stronger internal locus of control were associated with lower disability and better HRQL. Comorbid somatic symptoms contributed to high disability and low quality of life.

Conclusion: Psychological factors, such as illness perception, attribution and internal locus of control, were associated with disability and HRQL. These factors should be considered when designing treatments for individuals with COPD, and adequate interventions should be provided to enhance illness understanding and self-management skills.     

What good leaders actually do: micro-level leadership behaviour,leader evaluations,and team decision quality

We supplement broad definitions of leadership behaviour with the concept of micro-level leadership behaviour, leaders’ verbal and non-verbal visible conduct and interaction. For the context of team decision-making, we identify two potentially beneficial micro-level leadership behaviours, question asking and behavioural mimicry. Specifically, we propose that under conditions of informational complexity and unshared information, participative leadership is most appropriate for team decision-making, that its effects are mediated by inquiring and empathy, and that question asking and mimicry are the behavioural micro-level manifestations of inquiring and empathy. We thus hypothesize that the effect of participative leadership on team decision quality and leader evaluation is mediated by question asking and mimicry. We conduct a laboratory experiment with student teams working on a hidden profile decision-making task and measure question asking through behavioural coding and mimicry with motion sensors. Results show that the effect of participative leadership on decision quality is mediated by question asking, and that the effect of participative leadership on leader evaluation as transformational is mediated by leaders’ behavioural mimicry and question asking. Under control of these micro-level behaviours, team decision quality and leader evaluations were unrelated.     

Patterns of Metaperception in Adolescents with Social Anxiety: Mind Reading in the Classroom

Socially anxious adults display an interpretation bias toward anticipating threat such as a high probability of audience criticism even in nonthreatening social situations. They may also expect more negative audience reactions to self than to others acknowledging anxiety. Few studies have examined such biases in adolescents. We examined negative and positive metaperceptions (i.e., others’ perceived responses) in 13–16-year-old adolescents (n?=?655) with high vs. normal social anxiety in a hypothetical classroom scenario, in which the participants predicted the frequency of negative and positive classmate responses when imagining either themselves (self-referent metaperceptions) or a classmate (other-referent metaperceptions) with visible symptoms of social anxiety as the target persons giving a speech. We assessed social anxiety with the Social Anxiety Scale for Adolescents and metaperception using the Classroom Questionnaire of Social Anxiety and Interpersonal Cognition. Social anxiety was associated with negative self-referent metaperceptions to a greater degree than with negative other-referent metaperceptions. Compared with adolescents with normal social anxiety, those with high social anxiety (both boys and girls) predicted a broader range of negative classmate responses toward self, as compared with their predictions of negative responses toward a classmate. These group differences were observed specifically with regard to audience’s predicted covert negative responses (i.e., negative thoughts and feelings) toward self, indicating that socially anxious adolescents tend to mind-read. Minimal group differences in positive metaperceptions were observed. The results reveal target and content specificity in socially anxious adolescents’ negative metaperceptions.     

Begutachtung der posttraumatischen Belastungsstörung

There is a high prevalence of posttraumatic stress disorder in community-based samples; therefore psychiatric assessment and expert opinion is often required. Professional standards of psychiatric expert opinion in the assessment of posttraumatic stress disorder are outlined. The significance of symptom validity tests is critically discussed. Test results have to be considered carefully in the medicolegal context and require thorough clinical assessment.