Estimating individual treatment effects from multiple-baseline data: A Monte Carlo study of multilevel-modeling approaches

While conducting intervention research, researchers and practitioners are often interested in how the intervention functions not only at the group level, but also at the individual level. One way to examine individual treatment effects is through multiple-baseline studies analyzed with multilevel modeling. This analysis allows for the construction of confidence intervals, which are strongly recommended in the reporting guidelines of the American Psychological Association. The purpose of this study was to examine the accuracy of confidence intervals of individual treatment effects obtained from multilevel modeling of multiple-baseline data. Monte Carlo methods were used to examine performance across conditions varying in the number of participants, the number of observations per participant, and the dependency of errors. The accuracy of the confidence intervals depended on the method used, with the greatest accuracy being obtained when multilevel modeling was coupled with the Kenward—Roger method of estimating degrees of freedom.     

Few Preschool Boys and Girls with ADHD are Well-Adjusted During Adolescence

To estimate the prevalence of being well-adjusted in adolescence, boys and girls with (n = 96) and without (n = 126) attention-deficit/hyperactivity disorder (ADHD) were assessed seven times in eight years starting when they were 4–6 years of age. Symptoms of ADHD, ODD/CD, and depression/anxiety in addition to social skills and social preference were gathered using multiple methods and informants. Being well-adjusted was defined by surpassing thresholds in at least four of the five domains. At the 7- and 8-year follow-up, when youth were 11–14 years old, probands were significantly less likely to be well-adjusted relative to age- and ethnicity-matched control children. Only a minority of children with ADHD was well-adjusted in adolescence when emotional, behavioral, and social domains were considered simultaneously. Even when their ADHD symptoms improved over time, most probands exhibited significant impairment 7–8 years after their initial assessment.     

Common Genetic and Environmental Influences on Major Depressive Disorder and Conduct Disorder

The evidence for common genetic and environmental influences on conduct disorder (CD) and major depressive disorder (MDD) in adolescents was examined. A sample of 570 monozygotic twin pairs, 592 dizygotic twin pairs, and 426 non-twin siblings, aged 12-18 years, was recruited from the Colorado Twin Registry. For the past year data, there was a significant correlation between the genetic influences on MDD and CD and, for the lifetime data, there was a significant correlation between the genetic influences on MDD and CD, and a significant correlation between the nonshared environmental influences on MDD and CD. Our results suggest that some genetic factors will increase an individual's vulnerability to both MDD and CD in adolescence.     

Measuring Latinos' perceptions of depression: a confirmatory factor analysis of the Illness Perception Questionnaire

This study examined the psychometric properties of the Revised Illness Perception Questionnaire adapted for a clinical sample of low-income Latinos suffering from depression. Participants (N = 339) were recruited from public primary care centers. Their average age was 49.73 years and the majority was foreign born females of either Mexican or Central American descent. Confirmatory factor analysis was used to test the factor structure of this measure. Construct and discriminant validity and internal consistency were evaluated. After the elimination of three items because of low factor loadings (< .40) and the specification of seven error covariances, a revised model composed of 24 items had adequate goodness-of-fit indices and factor loadings, supporting construct validity. Each of the subscales reported satisfactory internal consistency. Intercorrelations between the 5 illness perception factors provided initial support for the discriminant validity of these factors in the context of depression. The establishment of the psychometric properties of this adapted measure will pave the way for future studies examining the role illness perceptions play in the help seeking and management of depression among Latinos.     

Self-objectification and ideal body shape for men and women

Objectification theory posits that valuing one's body for appearance rather than performance is associated with a range of negative psychological outcomes. This theory has been tested in women, but has received less empirical attention in men. This study examined the relation between self-objectification and ideal body shape in both men and women. One hundred eighty-three college students (111 women, 72 men) completed a questionnaire containing measures of self-objectification and ideal body shape (using a figure array ranging from non-muscular to very muscular). Consistent with hypotheses, women desired a less muscular body and men desired a more muscular body. Women also self-objectified more than men. In addition, there was an interaction between sex and self-objectification on ideal body shape. For women, higher self-objectification scores were related to a desire for a less muscular body. For men, higher self-objectification scores were related to a desire for a more muscular body. Self-objectification theory is a useful framework for understanding body image issues in men. However, the relation between self-objectification and other body related variables may differ for men and women.     

Young children's automatic encoding of social categories

The present research investigated young children's automatic encoding of two social categories that are highly relevant to adults: gender and race. Three‐ to 6‐year‐old participants learned facts about unfamiliar target children who varied in either gender or race and were asked to remember which facts went with which targets. When participants made mistakes, they were more likely to confuse targets of the same gender than targets of different genders, but they were equally likely to confuse targets within and across racial groups. However, a social preference measure indicated that participants were sensitive to both gender and race information. Participants with more racial diversity in their social environments were more likely to encode race, but did not have stronger racial preferences. These findings provide evidence that young children do not automatically encode all perceptible features of others. Further, gender may be a more fundamental social category than race.     

Initial examination of a multidimensional model of trauma-related guilt: Applications to combat veterans and battered women

Guilt is conceptualized as a multidimensional construct consisting of negative affect and a set of interrelated cognitions. Guilt magnitude is thought to be a function of the magnitudes of six variables posited as primary components of guilt: a negative event, distress, perceptions of responsibility, lack of justification, wrongdoing, and false beliefs about preoutcome knowledge. The model was tested with samples of Vietnam veterans and battered women. Participants rated their reactions to and perceived roles in trauma-related events. Among Vietnam veterans, distress ratings were highly correlated with guilt severity. Cognitive guilt-component variables were significantly correlated with guilt in both groups. In multiple regression, guilt components accounted for 61% of variance in veterans' guilt and 44% of variance in women's guilt. Among veterans, distress ratings were highly correlated with measures of PTSD and depression. In both groups, cognitive guilt-component variables were positively correlated with psychopathology. Results support the view that beliefs about one's role in trauma are important factors in posttrauma adjustment.     

Lexical co-occurrence and association strength

The 1-million-word Brown corpus was searched for co-occurrences of semantically related pairs of concrete nouns appearing within an arbitrary window of 250 characters. Related pairs of nouns (OCEAN-WATER) co-occur significantly more often than matched, unrelated pairs (OCEAN-HAND), and this difference remained significant within blocks of text up to 1000 characters in length. Frequency of co-occurrence, corrected for chance, is significantly correlated with association strength. Lexical distance between co-occurring members of a given pair is inversely correlated with association strength. Significantly more co-occurrences were found, per unit text, in the fictional sections of the corpus.