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Aim: We investigated neuropsychiatric outcomes in children with Noonan syndrome and addressed limitations in previous research with a focus on prepubertal children, comparison to typically developing children, comprehensive neuropsychiatric evaluation, and controlling for overall cognitive abilities. Method: Forty-five children with Noonan syndrome (mean = 8 years 6 months, SD = 2 years 2 months; 29 females) and 40 typically developing children (mean = 8 years 9 months, SD = 2 years; 22 females) were evaluated with objective, parent-report, and psychiatric interview measures. Results: Children with Noonan syndrome demonstrated elevated symptoms across attention-deficit/hyperactivity disorder (ADHD) (attention, hyperactivity, and inhibition), autism spectrum disorder (ASD) (maintaining social relationships, behavioral rigidity, and sensory sensitivity), and oppositional defiant disorder (ODD) (aggression) symptom clusters relative to typically developing children (all p < 0.05). Group differences in nearly all parent-report measures were significant after accounting for variations in intellectual functioning, suggesting that increased neurodevelopmental symptoms are not simply driven by overall intelligence. Twenty out of 42 children with Noonan syndrome met criteria for ADHD, eight out of 42 for ODD, and 11 out of 43 demonstrated clinically significant symptoms seen in children with ASD. Interpretation: Children with Noonan syndrome are at increased risk for a range of ADHD, ASD, and ODD associated symptoms. A dimensional approach reveals significant ASD symptoms in Noonan syndrome that do not emerge when using the currently accepted categorical diagnostic approach. [ABSTRACT FROM AUTHOR]

Turner syndrome (TS) is a common sex chromosome aneuploidy in females associated with various physical, cognitive, and socio‐emotional phenotypes. However, few studies have examined TS‐associated alterations in the development of cortical gray matter volume and the two components that comprise this measure—surface area and thickness. Moreover, the longitudinal direct (i.e., genetic) and indirect (i.e., hormonal) effects of X‐monosomy on the brain are unclear. Brain structure was assessed in 61 girls with TS (11.3 ± 2.8 years) and 55 typically developing girls (10.8 ± 2.3 years) for up to 4 timepoints. Surface‐based analyses of cortical gray matter volume, thickness, and surface area were conducted to examine the direct effects of X‐monosomy present before pubertal onset and indirect hormonal effects of estrogen deficiency/X‐monosomy emerging after pubertal onset. Longitudinal analyses revealed that, whereas typically developing girls exhibited normative declines in gray matter structure during adolescence, this pattern was reduced or inverted in TS. Further, girls with TS demonstrated smaller total surface area and larger average cortical thickness overall. Regionally, the TS group exhibited decreased volume and surface area in the pericalcarine, postcentral, and parietal regions relative to typically developing girls, as well as larger volume in the caudate, amygdala, and temporal lobe regions and increased thickness in parietal and temporal regions. Surface area alterations were predominant by age 8, while maturational differences in thickness emerged by age 10 or later. Taken together, these results suggest the involvement of both direct and indirect effects of X‐chromosome haploinsufficiency on brain development in TS. [ABSTRACT FROM AUTHOR]

Background: There has been steadily increasing use of bilateral mastectomy (BMX) in the treatment of primary breast cancer (BC). In this study, we utilized functional magnetic resonance imaging (fMRI) to examine the influence of emotion regulation on the decision of newly diagnosed BC patients to choose BMX rather than non‐BMX treatments. Methods: We recruited 123 women with unilateral BC, 61 of whom received BMX and 62 of whom received non‐BMX treatments, and 39 healthy controls. While participants were in the fMRI scanner, we showed them BC‐related and non‐BC‐negative images. In one condition, they were instructed to watch the images naturally. In another, they were instructed to regulate their negative emotion. We compared the fMRI signal during these conditions throughout the brain. Results: With non‐BC‐negative images as the baseline, BC patients showed greater self‐reported reactivity and neural reactivity to BC‐related images in brain regions associated with self‐reflection than did controls. Among the BC patients, the BMX group showed weaker activation in prefrontal emotion regulation brain regions during emotion regulation than did the non‐BMX group. Conclusions: BC patients are understandably emotionally hyper‐reactive to BC‐related stimuli and those who ultimately received BMX experience more difficulty in regulating BC‐related negative emotion than non‐BMX BC patients. These findings offer neuropsychological evidence that difficulty in managing anxiety related to the possibility of cancer recurrence is a factor in surgical treatment decision‐making and may be an intervention target with the goal of strengthening the management of cancer‐related anxiety by nonsurgical means. Trial Registration: NCT03050463. [ABSTRACT FROM AUTHOR]

Objectives: To delineate midlife personality dimensions of early cognitive change in an age-homogenous sample of U.S. older adults. Design: Longitudinal study of 6133 adults from the Wisconsin Longitudinal Study (WLS). Measures: Middle-aged participants (mean age = 53.2; SD = 0.6) from the WLS completed the 'Big-5' personality assessment in 1992. Mixed effects models examined whether midlife personality traits were associated with change in cognitive performance from participant's mid-60s (2004-2005) to early 70s (2011). The cognitive battery assessed abstract reasoning (AR), category fluency (CF), working memory (WM), and delayed verbal memory (DVM). Models adjusted for sex, education, and subjective health. Results: High Openness was a significant predictor of change in AR, CF, and DVM. These cognitive outcomes declined less among those with high Openness, but the effect sizes for Openness by time were small (R²s < 0.01). AR and CF were characterized by higher overall performance with high Openness, but with relatively parallel change for the highest and lowest Openness quartiles. There was no advantage of Openness to DVM by the second assessment. High Conscientiousness was a predictor of more change for DVM, though the effect size was small (R² < 0.01). Conclusions: None of the midlife personality traits were uniformly associated with change in cognitive performance in early older adulthood. High midlife Openness had the most noteworthy impact on cognition. Interventions designed to target Openness have potential to elevate and maintain a higher threshold of performance in some cognitive domains, but may only have a small impact on cognitive change. [ABSTRACT FROM AUTHOR]

The neurobiology of autism has been shown to involve alterations in cortical morphology and gamma‐aminobutyric acid A (GABAA) receptor density. We hypothesized that GABAA receptor binding potential (GABAAR BPND) would correlate with cortical thickness, but their correlations would differ between autistic adults and typically developing (TD) controls. We studied 50 adults (23 autism, 27 TD, mean age of 27 years) using magnetic resonance imaging to measure cortical thickness, and [18F]flumazenil positron emission tomography imaging to measure GABAAR BPND. We determined the correlations between cortical thickness and GABAAR BPND by cortical lobe, region‐of‐interest, and diagnosis of autism spectrum disorder (ASD). We also explored potential sex differences in the relationship between cortical thickness and autism characteristics, as measured by autism spectrum quotient (AQ) scores. Comparing autism and TD groups, no significant differences were found in cortical thickness or GABAAR BPND. In both autism and TD groups, a negative relationship between cortical thickness and GABAAR BPND was observed in the frontal and occipital cortices, but no relationship was found in the temporal or limbic cortices. A positive correlation was seen in the parietal cortex that was only significant for the autism group. Interestingly, in an exploratory analysis, we found sex differences in the relationships between cortical thickness and GABAAR BPND, and cortical thickness and AQ scores in the left postcentral gyrus. Lay Summary: The thickness of the brain cortex and the density of the receptors associated with inhibitory neurotransmitter GABA have been hypothesized to underlie the neurobiology of autism. In this study, we found that these biomarkers correlate positively in the parietal cortex, but negatively in the frontal and occipital cortical regions of the brain. Furthermore, we collected preliminary evidence that the correlations between cortical thickness and GABA receptor density are sexdependent in a brain region where sensory inputs are registered. [ABSTRACT FROM AUTHOR]

Aim: To study sex differences in attention‐deficit/hyperactivity disorder (ADHD) symptoms, we explored whether X chromosome absence or excess is independently associated with deficits in attention and hyperactivity, executive function, and processing speed. Method: We assessed 116 children (ages 3y 10mo–11y 11mo, mean 8y 5mo, SD 1y 11mo) with a variable number of sex chromosomes: 36 females with Turner syndrome (45, X0), 20 males with Klinefelter syndrome (47, XXY), 37 typically developing females (XX), and 23 typically developing males (XY). Results: X chromosome absence was associated with increased attention problems, hyperactivity, and deficits in inhibitory control, compared with female children with XX (all p<0.003). Conversely, X chromosome excess was associated with weakness in working memory (p=0.018) and approached significance for attention problems (p=0.071) but not with hyperactivity, or weakness in inhibitory control relative to male children with XY. Using non‐parametric effect size to quantify the clinical effect revealed that X chromosome absence affected attention, hyperactivity, executive function, and processing speed (all r>0.4), while X excess affected in‐laboratory as well as parent‐reported working memory (all r>0.4). Interpretation: Our observations provide compelling evidence that the absence or excess of an X chromosome distinctly affects cognition and behaviors associated with ADHD. Video Podcast https://youtu.be/eFzWpLv_OHk [ABSTRACT FROM AUTHOR]

Background: Breast cancer survivors often have persisting headache. In a secondary analysis of the Brief Behavioral Therapy for Cancer‐Related Insomnia (BBT‐CI) clinical trial (ClinicalTrials.gov identifier NCT02165839), the authors examined the effects of BBT‐CI on headache outcomes in patients with breast cancer. Methods: Patients with breast cancer who were receiving chemotherapy were randomly assigned to receive either the BBT‐CI intervention or the Healthy EAting Education Learning for healthy sleep (HEAL) control intervention, and both were delivered over 6 weeks by trained staff. Headache outcomes and heart rate variability (HRV) were measured at baseline, 6 weeks, 6 months, and 12 months. Mixed‐effects models were used to examine longitudinal headache outcomes in the groups according to the intention to treat. Principal component analysis and agglomerative hierarchical clustering were conducted to reduce 16 variables for data‐driven phenotyping. Results: Patients in the BBT‐CI arm (n = 73) exhibited a significant reduction in headache burden over time (P =.02; effect size [Cohen d] = 0.43), whereas the reduction was not significant among those in the HEAL arm (n = 66). The first principal component was positively loaded by headache, sleep, fatigue, and nausea/vomiting and was negatively loaded by cognitive, physical, and emotional functioning. Agglomerative hierarchical clustering revealed 3 natural clusters. Cluster I (n = 58) featured the highest burden of headache, insomnia, and nausea/vomiting; cluster II (n = 50) featured the lowest HRV despite a low burden of headache and insomnia; and cluster III (n = 31) showed an inverse relation between HRV and headache‐insomnia, signifying autonomic dysfunction. Conclusions: BBT‐CI is efficacious in reducing headache burden in breast cancer survivors. Patient phenotyping demonstrates a headache type featuring sleep disturbance, nausea/vomiting, and low physical functioning—revealing similarities to migraine. Lay Summary: Breast cancer survivors often have persisting headache symptoms.In patients with cancer, treatment of chronic headache disorders using daily medications may be challenging because of drug interactions with chemotherapy and other cancer therapies as well as patients' reluctance to add more drugs to their medicine list.Headache and sleep disorders are closely related to each other.This study demonstrates that a sleep behavioral therapy reduced headache burden in breast cancer survivors.In addition, the majority of headache sufferers had a headache type with similarities to migraine—featuring sleep disturbance, nausea/vomiting, and low physical functioning. Breast cancer survivors often have persisting headache and insomnia burden. This study shows that a sleep behavioral therapy reduces headache burden in breast cancer survivors. [ABSTRACT FROM AUTHOR]

This study investigated group differences and longitudinal changes in brain volume before and after trauma‐focused cognitive behavioral therapy (TF‐CBT) in 20 unmedicated youth with maltreatment‐related posttraumatic stress disorder (PTSD) and 20 non–trauma‐exposed healthy control (HC) participants. We collected MRI scans of brain anatomy before and after 5 months of TF‐CBT or the same time interval for the HC group. FreeSurfer software was used to segment brain images into 95 cortical and subcortical volumes, which were submitted to optimal scaling regression with lasso variable selection. The resulting model of group differences at baseline included larger right medial orbital frontal and left posterior cingulate corticies and smaller right midcingulate and right precuneus corticies in the PTSD relative to the HC group, R2 =.67. The model of group differences in pre‐ to posttreatment change included greater longitudinal changes in right rostral middle frontal, left pars triangularis, right entorhinal, and left cuneus corticies in the PTSD relative to the HC group, R2 =.69. Within the PTSD group, pre‐ to posttreatment symptom improvement was modeled by longitudinal decreases in the left posterior cingulate cortex, R2 =.45, and predicted by baseline measures of a smaller right isthmus (retrosplenial) cingulate and larger left caudate, R2 =.77. In sum, treatment was associated with longitudinal changes in brain regions that support executive functioning but not those that discriminated PTSD from HC participants at baseline. Additionally, results confirm a role for the posterior/retrosplenial cingulate as a correlate of PTSD symptom improvement and predictor of treatment outcome. [ABSTRACT FROM AUTHOR]

Objective: This exploratory study is the first to examine family‐based treatment (FBT) adherence and association to treatment outcome in the context of a large‐scale, multi‐centre study for the treatment of adolescents with anorexia nervosa. Method: One hundred and ninety recorded FBT sessions from 68 adolescents with anorexia nervosa and their families were recruited across multiple sites (N = 6). Each site provided 1–4 tapes per family over four treatment time points, and each was independently rated for therapist adherence. Results: There were differences in adherence scores within and between sites. ANOVA produced a main effect for site, F(5, 46) = 8.6, p <.001, and phase, F(3, 42) = 12.7, p <.001, with adherence decreasing in later phases. Adherence was not associated to end of treatment percent ideal body weight after controlling for baseline percent ideal body weight (r =.088, p =.48). Conclusions: Results suggest that FBT can be delivered with adherence in phase one of treatment. Adherence was not associated with treatment outcome as determined using percent ideal body weight. [ABSTRACT FROM AUTHOR]

Background: Currently, there are eight meta‐analyses that address the question whether psychosocial intervention can prolong survival with widely disparate conclusions. One reason for inconsistent findings may be the methods by which previous meta‐analyses were conducted. Methods: Databases were searched to identify valid randomized controlled trials that compared psychosocial intervention with usual care. Hazard ratios (HRs) and their confidence intervals were pooled to estimate the strength of the treatment effect on survival time, and z‐tests were performed to assess possible heterogeneity of effect sizes associated with different patient and treatment characteristics. Results: Twelve trials involving 2439 cancer patients that met screening criteria were included. The overall effect favored the treatment group with a HR of 0.71 (95% Cl 0.58‐0.88; P = 0.002). An effect size favoring treatment group was observed in studies sampling lower vs higher percentage of married patients' (NNT = 4.3 vs NNT = 15.4), when Cognitive‐Behavioral Therapy was applied at early vs late cancer stage (NNT = 2.3 vs NNT = −28.6), and among patients' older vs younger than 50 (NNT = 4.2 vs NNT = −20.5). Conclusions: Psychosocial interventions may have an important effect on survival. Reviewed interventions appear to be more effective in unmarried patients, patients who are older, and those with an early cancer stage who attend CBT. Limitations of previous meta‐analysis are discussed. Psychosocial interventions may have an important effect on survival. Reviewed interventions appear to be more effective in unmarried patients, patients who are older, and those with early cancer stage who attend CBT. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Family‐based treatment (FBT) for adolescent anorexia nervosa (AN) promotes faster weight restoration when compared to other treatments. However, the mechanisms through which this occurs are not clarified. This study explored the trajectories of parental self‐efficacy and perceived family flexibility during FBT and systemic family therapy (SyFT). We also explored whether parental self‐efficacy mediates the effects of treatment on weight gain early in treatment. Method: 158 adolescents (12–18 years old; 89% girls) and their parents were randomized to FBT or SyFT. Parental self‐efficacy as well as adolescents' and parental perceptions of the family's flexibility were collected at baseline and at sessions 2, 4, 6, and 8. Results: Over time, only parents in FBT reported significantly greater self‐efficacy. The change in maternal self‐efficacy over the first 8 weeks of treatment was a significant mediator of session 10 weight gain. There were no significant group differences in perceived flexibility by session 8. Discussion: Both parents in FBT and mothers in SyFT understand early the need to change their family's rules and roles. However, the specific strategies of FBT appear to mediate early weight gain in AN. [ABSTRACT FROM AUTHOR]

Adolescents with anorexia nervosa who have obsessive-compulsive (OC) features respond poorly to family-based treatment (FBT). This study evaluated the feasibility of combining FBT with either cognitive remediation therapy (CRT) or art therapy (AT) to improve treatment response in this at-risk group. Thirty adolescents with anorexia nervosa and OC features were randomized to 15 sessions of FBT + CRT or AT. Recruitment rate was 1 per month, and treatment attrition was 16.6% with no differences between groups. Suitability, expectancy and therapeutic relationships were acceptable for both combinations. Correlations between changes in OC traits and changes in cognitive inefficiencies were found for both combinations. Moderate changes in cognitive inefficiencies were found in both groups but were larger in the FBT + AT combination. This study suggests that an RCT for poor responders to FBT because of OC traits combining FBT with either CRT or AT is feasible to conduct. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association. [ABSTRACT FROM AUTHOR]

From the statistical learning perspective, this paper shows a new direction for the use of growth mixture modeling (GMM), a method of identifying latent subpopulations that manifest heterogeneous outcome trajectories. In the proposed approach, we utilize the benefits of the conventional use of GMM for the purpose of generating potential candidate models based on empirical model fitting, which can be viewed as unsupervised learning. We then evaluate candidate GMM models on the basis of a direct measure of success; how well the trajectory types are predicted by clinically and demographically relevant baseline features, which can be viewed as supervised learning. We examine the proposed approach focusing on a particular utility of latent trajectory classes, as outcomes that can be used as valid prediction targets in clinical prognostic models. Our approach is illustrated using data from the Longitudinal Assessment of Manic Symptoms study. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective We examined the timing and number of days of hospitalization during the course of treatment, hospitalization effects on outcome, and predictors and moderators of the use of hospitalization in adolescents with anorexia nervosa (AN). Method Data used in this study were collected from 158 adolescents (ages 12 to 18 years of age) who met DSM-IVTR criteria for AN (exclusive of the amenorrhea criteria) randomized to receive either Family Based Treatment (FBT) or Systemic Family Therapy (SyFT) in a 7 site study. Results The trajectory of hospital day use is similar in the first 5 weeks irrespective of treatment allocation. However, days of hospitalization continued to increase throughout SyFT but leveled off in FBT after ∼5 weeks of treatment. Early hospitalization was a negative predictor for improvements in percent weight change for both treatment groups ( t(1)=2.6, p = 0.011). Co-morbid psychopathology predicted early hospital use in both treatments. Higher levels of eating related obsessions and depression moderated hospitalization rates suggesting that FBT reduces early hospitalization rates compared to SyFT for these subgroups. Discussion These data support and extend findings from previous studies by identifying patterns of hospital use, and predictors and moderators of treatment effect for early hospitalization use in adolescent AN. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:891-894) [ABSTRACT FROM AUTHOR]

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We propose a principal stratification approach to assess causal effects in nonrandomized longitudinal comparative effectiveness studies with a binary endpoint outcome and repeated measures of a continuous intermediate variable. Our method is an extension of the principal stratification approach originally proposed for the longitudinal randomized study 'Prevention of Suicide in Primary Care Elderly: Collaborative Trial' to assess the treatment effect on the continuous Hamilton depression score adjusting for the heterogeneity of repeatedly measured binary compliance status. Our motivation for this work comes from a comparison of the effect of two glucose-lowering medications on a clinical cohort of patients with type 2 diabetes. Here, we consider a causal inference problem assessing how well the two medications work relative to one another on two binary endpoint outcomes: cardiovascular disease-related hospitalization and all-cause mortality. Clinically, these glucose-lowering medications can have differential effects on the intermediate outcome, glucose level over time. Ultimately, we want to compare medication effects on the endpoint outcomes among individuals in the same glucose trajectory stratum while accounting for the heterogeneity in baseline covariates (i.e., to obtain 'principal effects' on the endpoint outcomes). The proposed method involves a three-step model estimation procedure. Step 1 identifies principal strata associated with the intermediate variable using hybrid growth mixture modeling analyses. Step 2 obtains the stratum membership using the pseudoclass technique and derives propensity scores for treatment assignment. Step 3 obtains the stratum-specific treatment effect on the endpoint outcome weighted by inverse propensity probabilities derived from Step 2. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives The Longitudinal Assessment of Manic Symptoms ( LAMS) study was designed to investigate phenomenology and establish predictors of functional outcomes in children with elevated manic symptoms. The purpose of this series of analyses was to determine whether the participants demonstrated different trajectories of parent-reported manic and biphasic symptoms over the first 24 months of follow-up and to describe the clinical characteristics of the trajectories. Methods The 707 participants were initially aged 6-12 years and ascertained from outpatient clinics associated with the four university-affiliated LAMS sites. There were 621 children whose parents/guardians' ratings scored ≥ 12 on the Parent General Behavior Inventory-10-item Mania Form ( PGBI-10M) and a matched random sample of 86 children whose parents/guardians' ratings scored ≤ 11 on the PGBI-10M. Participants were seen every six months after the baseline and their parents completed the PGBI-10M at each visit. Results For the whole sample, manic symptoms decreased over 24 months (linear effect B = −1.15, standard error = 0.32, t = −3.66, p < 0.001). Growth mixture modeling revealed four unique trajectories of manic symptoms. Approximately 85% of the cohort belonged to two classes in which manic symptoms decreased. The remaining ~15% formed two classes ( high and rising and unstable) characterized by the highest rates of diagnostic conversion to a bipolar disorder (all p-values < 0.001). Conclusions Outcomes are not uniform among children with symptoms of mania or at high risk for mania. A substantial minority of clinically referred children shows unstable or steadily increasing manic symptoms, and these patterns have distinct clinical correlates. [ABSTRACT FROM AUTHOR]

Objective There are limited data supporting specific treatments for adults with anorexia nervosa (AN). Randomized clinical trials (RCTs) for adults with AN are characterized by high attrition limiting the feasibility of conducting and interpreting existing studies. High dropout rates may be related to the inflexible and obsessional cognitive style of patients with AN. This study evaluated the feasibility of using cognitive remediation therapy (CRT) to reduce attrition in RCTs for AN. Method Forty-six participants (mean age of 22.7 years and mean duration of AN of 6.4 years) were randomized to receive eight sessions of either CRT or cognitive behavioral therapy (CBT) over 2 months followed by 16 sessions of CBT for 4 months. Results During the 2-month CRT vs. CBT treatment, rates of attrition were lower in CRT (13%) compared with that of CBT (33%). There were greater improvements in cognitive inefficiencies in the CRT compared with that of the CBT group at the end of 2 months. There were no differences in other outcomes. Discussion These results suggest that CRT is acceptable and feasible for use in RCTs for outpatient treatment of AN. CRT may reduce attrition in the short term. Adequately powered future studies are needed to examine CRT as an outpatient treatment for AN. © 2013 by Wiley Periodicals, Inc. (Int J Eat Disord 2013; 46:567-575) [ABSTRACT FROM AUTHOR]

We examine the practicality of propensity score methods for estimating causal treatment effects conditional on intermediate posttreatment outcomes (principal effects) in the context of randomized experiments. In particular, we focus on the sensitivity of principal causal effect estimates to violation of principal ignorability, which is the primary assumption that underlies the use of propensity score methods to estimate principal effects. Under principal ignorability (PI), principal strata membership is conditionally independent of the potential outcome under control given the pre-treatment covariates; i.e. there are no differences in the potential outcomes under control across principal strata given the observed pretreatment covariates. Under this assumption, principal scores modeling principal strata membership can be estimated based solely on the observed covariates and used to predict strata membership and estimate principal effects. While this assumption underlies the use of propensity scores in this setting, sensitivity to violations of it has not been studied rigorously. In this paper, we explicitly define PI using the outcome model (although we do not actually use this outcome model in estimating principal scores) and systematically examine how deviations from the assumption affect estimates, including how the strength of association between principal stratum membership and covariates modifies the performance. We find that when PI is violated, very strong covariate predictors of stratum membership are needed to yield accurate estimates of principal effects. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In cluster randomized trials (CRTs), individuals belonging to the same cluster are very likely to resemble one another, not only in terms of outcomes but also in terms of treatment compliance behavior. Although the impact of resemblance in outcomes is well acknowledged, little attention has been given to the possible impact of resemblance in compliance behavior. This study defines compliance intraclass correlation as the level of resemblance in compliance behavior among individuals within clusters. On the basis of Monte Carlo simulations, it is demonstrated how compliance intraclass correlation affects power to detect intention-to-treat (ITT) effect in the CRT setting. As a way of improving power to detect ITT effect in CRTs accompanied by noncompliance, this study employs an estimation method, where ITT effect estimates are obtained based on compliance-type-specific treatment effect estimates. A multilevel mixture analysis using an ML-EM estimation method is used for this estimation. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

During the summer vacation children who are economically disadvantaged experience declines in reading achievement, while middle- and high-income children improve. Previous research has demonstrated that the most widely implemented intervention– sending economically disadvantaged students to summer school– has not led to increases in reading achievement. In this longitudinal randomised trial, a randomly assigned group of exiting First-Grade children who were economically disadvantaged was enrolled in a seven-week summer reading day camp. The intervention students' reading achievement was then compared to control group participants at four time points. Results showed noteworthy differences for intervention students in reading comprehension. [ABSTRACT FROM AUTHOR]