Laypeople do use sample variance: The effect of embedding data in a variance-implying story

When using sample data to decide whether two populations differ, laypeople attend to the difference between group means, but largely overlook within-group variability (Obrecht, Chapman, & Gelman, 2007 Obrecht, N. A., Chapman, G. B. and Gelman, R. 2007. Intuitive t-tests: Lay use of statistical information. Psychonomic Bulletin & Review, 14: 1147–1152.  [Google Scholar]). We show, first, that laypeople know about and use story-implied variability when making pairwise comparisons. Then we demonstrate that participants’ sensitivity to variance in a dataset is boosted when presented in a context that implies consistent variance information. Statistical data were couched in stories about electrical conductivity measurements obtained from element samples (low-variability category) or body weight measurements from samples of peoples (high-variability category). We manipulated, between participants, whether the data variance matched or mismatched the story-implied variability. Participants who received data in a matching context showed high sensitivity to variance, while those in the mismatching condition did not. Laypeople use statistical data to make reasonable inferences when those data are provided in a context that makes sense.     

Understanding smoking after acute illness: An application of the sentinel event method

The sentinel event theory provides a stepwise approach for building models to understand how negative events can spark health behaviour change. This study tested a preliminary model using the sentinel events method in a sample (N = 300) of smokers who sought care for acute cardiac symptoms. Patients completed measures on: smoking-related causal attribution, perceived severity of the acute illness event, illness-related fear and intentions to quit smoking. Patients were followed up one week after the health event and a seven-day timeline follow back was completed to determine abstinence from tobacco. Structural equation models were performed using average predictor scale scores at baseline, as well as three different time anchors for ratings of illness severity and illness-related fear. Quit intentions, actual illness severity and age were the consistent, positive and independent predictors of seven-day point prevalence abstinence. Additional research on the influences of perceptions and emotional reactions is warranted.     

Measuring Quality of Life: A Case for Re-Examining the Assessment of Domain Importance Weighting

Domain importance weighting has long been a topic of debate in the study of quality of life (QoL). The purpose of this study is to examine the adequacy of popular approaches used to assess domain importance weighting with QoL measures that follow a formative-indicator approach. Using both empirical and simulation data, this study found that neither of the two popular methods of evaluating the performance of domain importance weighting in QoL measures, correlation and moderated regression analysis, was ideal in capturing the actual function domain importance weighting posited in the data. More specifically, results from the popular approaches used to assess domain importance weighting could be quite misleading when QoL measures were constructed using a formative-indicator approach. These findings call for a careful re-examination of results from previous studies using those popular approaches to assess domain importance weighting in QoL measures.     

Emotion Regulation Mediates the Association Between ADHD and Depressive Symptoms in a Community Sample of Youth

The purpose of this study was to examine the longitudinal relationship between attention-deficit/hyperactivity disorder (ADHD) symptoms, emotion regulation (ER) ability, and depressive symptoms within a diverse community sample of 277 youth, ages 9–12 (56 % male). Participants were drawn from a larger study examining adolescent risk behaviors, and completed annual assessments over 3 years. Youth ADHD symptoms were assessed at Time 1 (T1) using the parent-reported Disruptive Behavior Disorders Rating Scale, ER was assessed with the parent-reported Emotion Regulation Checklist at Time 2 (T2), and youth depressive symptoms were assessed using the self-reported Revised Child Anxiety and Depression Scales at Time 3 (T3). Analyses examined T2 ER as a mediator between T1 ADHD symptoms (including the unique contributions of inattentive [IA] versus hyperactive/impulsive [HI] symptoms) and T3 depressive symptoms. Structural equation modeling (SEM) indicated the path model specified provided an excellent fit to the data. Tests of indirect effects suggested that T2 ER appears to be a significant mechanism that underlies the relationship between T1 ADHD and T3 depression, even when accounting for T1 oppositional defiant and depressive symptoms. Furthermore, while both T1 IA and HI symptoms had significant indirect effects on T3 depression through the mechanism T2 ER, HI proved a more robust predictor of T2 ER than IA. Results of this prospective study support cross-sectional findings pointing to ER as a potential mechanism linking ADHD and depressive symptoms in youth. Clinical implications and future directions are discussed.     

The influence of social consensus information on intergroup attitudes: the moderating effects of ingroup identification

Two studies examined the role of ingroup identification in the influence of social consensus information (information about others' beliefs) on intergroup attitudes. Research demonstrates that consensus information influences individuals' intergroup attitudes. However, the extent to which individuals identify with the group providing consensus information seems important to understanding consensus effects. In Study 1, 100 high or low ingroup identifiers received information that other ingroup members held favorable or unfavorable attitudes toward African Americans and then provided their own attitudes. In Study 2, 250 participants completed an ingroup identification manipulation (high, low, or control) before receiving favorable or no consensus information. Results of both studies demonstrated that ingroup identification moderated consensus effects, such that high identifiers were more susceptible to others' beliefs than individuals in the low identification and control conditions. In determining critical factors involved in consensus effects, we hope to create a useful method to promote favorable intergroup attitudes and behaviors.     

Social Status and Relational System of Elderly Suicides: A Reexamination of the Henry-Short Thesis*

ABSTRACT: The relationship between status and suicide has not been clearly established. Henry and Short suggested a direct relationship, but subsequent research has proposed an inverse association. The present study of elderly males uses information obtained from two sources: (a) a random sample of the aged population studied in Pinellas County, Florida, in 1959; and (b) persons aged 65 and over who committed suicide in that county between 1955 and 1963. The major findings are: (a) the highest suicide rate is found at the lowest class level, suggesting an inverse relationship; (b) class differential in suicide is explained by a direct relationship between class and the relational system; and (c) controlling on the relational system results in a direct association between class and suicide. Thus, both status and the relational system operate independently and jointly to affect suicide rates of these elderly males. Findings suggest that both Henry and Short and later investigators are partially correct. The relationship between status and suicide may be clarified by taking into account other factors which are class related but which perhaps are more significant than measures of class alone.     

Factor Composition of the Suicide Intent Scale

An exploratory analysis of the Suicide Intent Scale was performed on a sample of 98 psychiatric inpatients who had made suicide attempts. The factor analysis was performed using a method for polychotomous data, and resulted in a two-factor solution. The Lethal Intent factor contained items pertaining to the subjective level of lethal intent, while the Planning factor contained items largely related to objective planning for the attempt. Preliminary analysis of these factors suggest that the Suicide Intent Scale can be used to evaluate two separate aspects of suicidal behavior.