William R. Smith

Park-Based Physical Activity Among Children and Adolescents

BACKGROUNDnAvailability of parks is associated with higher levels of physical activity among children and adolescents. Few studies examine actual park use and park-based physical activity in these populations.nnnPURPOSEnThis study examined associations among individual, park, and neighborhood environmental characteristics and childrens and adolescents park-based physical activity.nnnMETHODSnData were collected in 2007 on 2712 children in 20 randomly selected parks in Durham NC. The System for Observing Play and Recreation in Communities (SOPARC) provided measures of physical activity. Hierarchic regression analysis assessed associations among individual, park, and neighborhood environmental characteristics and childrens park-based physical activity. Data were analyzed in 2010.nnnRESULTSnOf the 2712 children observed, 34.2% and 13.2% were engaged in walking or vigorous physical activity. Environmental features of parks were associated with activity levels whereas neighborhood characteristics were not. Physical activity was negatively associated with gender (girls) (p=0.003); presence of a parent (p<0.0001); presence of nonparental adult (p=0.006); and an interaction involving the 0-5 years age group and style of play (p=0.017). Higher level of physical activity was associated with presence of other active children (p<0.0001); courts (e.g., basketball); and an interaction between number of recreation facilities and formal activities (p=0.004).nnnCONCLUSIONSnThese social factors and design features should be considered in order to stimulate higher levels of park-based physical activity among children and adolescents.

Constructing actuarial devices for predicting recidivism: a comparison of methods

A recent contribution to the prediction literature by Steadman et al. features a novel “iterative classification” procedure for constructing risk screening devices. In this article, the authors apply the iterative classification procedure to a large recidivism data set, across a range of recidivism outcomes and cross-validation conditions. The purpose of this study is to assess the generalizability of the iterative classification procedure and to draw comparisons with more traditional methods of device construction. Results show the iterative classification procedure to outperform other standard device construction procedures in terms of the percentage of cases classified as high or low risk but not to outperform more traditional device construction procedures on a variety of other performance measures. Implications for future research on the construction and evaluation of risk screening devices are discussed.

Burden of illness.

The burden of affective disorders includes costs and the pain and suffering of affected individuls. Burden can be perceived from social and private perspectives. Although no ideal measure of burden exists, ample evidence documents the extensive cost and other negative impacts of affective disorders. Affective disorders are associated with disruptive family relations, higher health care costs for comorbid conditions, elevated rates of suicide, and lower productivity. Reserch should focus on improving measures of burden in general and on quantifying burden from the standpoint of diverse population groups.

Park Use Among Youth and Adults: Examination of Individual, Social, and Urban Form Factors

This article examines park use in relation to neighborhood social (safety and poverty) and urban form (pedestrian infrastructure and street network pattern) characteristics among youth and adult subpopulations defined by age and gender. We utilized System for Observing Play and Recreation in Communities (SOPARC) and Geographic Information Systems to objectively measure park use and park and neighborhood characteristics in 20 neighborhood parks. Heterogeneous negative binomial regression models indicated that the relationship between park use and types of activity settings, and park use and neighborhood attributes vary by age and gender. In general, the study found that park and activity setting size; activity settings such as playgrounds, basketball courts, pool and water features, shelters, and picnic areas; and availability of sidewalks and intersections in the park’s neighborhood were positively associated with park use, whereas crime, poverty, and racial heterogeneity of the surrounding neighborhood were negatively associated with park use.

Community-based interventions.

This paper explores the potential of community-based, public health-oriented interventions as a tool for reducing the burden of affective disorders on individuals, their families, and communities. The paper reviews the use of community-based interventions with other health-related problems and describes potential applicability for affective disorders such as changing public attitudes, reducing social stigma, facilitating access, or supporting treatment adherence for populations in their community settings. An agenda for developing this field of intervention research is proposed.

Childcare Outdoor Renovation as a Built Environment Health Promotion Strategy: Evaluating the Preventing Obesity by Design Intervention

Purpose. To evaluate the effectiveness of Preventing Obesity by Design (POD), a childcare center outdoor renovation intervention. Design. Pre-post intervention evaluation. Setting. North Carolina licensed childcare centers (N = 27). Subjects. Preschool children. Intervention. Outdoor renovation, teacher training. Measures. Behavior mapping, Preschool Outdoor Environment Measurement Scale (POEMS), center director interview. Analysis. Descriptive statistics, ordinary least squares and logistic regressions calculated to assess levels of association between environmental change, childrens physical activity (PA), social behaviors, and environmental quality. Qualitative interview data analyzed to help understand intervention impact. Results. Behavior mapping showed that site layout attributes, such as the form (i.e., “single loop” and “double loop”) of pathways (functioning as circulation routes and wheeled toy settings), are associated with higher levels of PA. Teacher interaction was associated with decreased childrens PA. Absence of teacher or lack of child/child interaction was associated with increased PA. POEMS assessment of environmental quality was higher after renovation. POEMS domains (Physical Space and Teacher/Caregiver Roles) were positively associated with PA. After renovation, 68% of center directors reported positive changes in childrens behavior and 40% mentioned edible plant installations as greatest success. Conclusion. Built environment renovation of childcare center outdoors, including looped pathways installation, coupled with teacher training, may support increased PA. Renovation, including food gardens, may be a key to success for preschool health promotion and support change in childcare policy.

The Effects of Base Rate and Cutoff Point Choice on Commonly Used Measures of Association and Accuracy in Recidivism Research

Several measures of association and accuracy commonly used in the recidivism literature are examined for their sensitivity to variations in the proportion observed to recidivate (the base rate) and in the proportion selected for classification as recidivists (selection ratio). Logistic regression models are employed on a sample of 11,749 convicted offenders to generate predicted probabilities of four recidivism criteria varying in base rates from 0.06 to 0.48. Cutoff point selections from 0.1 to 0.9 show the effects of cutoff point changes on the following commonly used measures of association and accuracy: RIOC (relative improvement over chance), MCR (mean cost rating), Φ, γ, PRE (proportion reduction in error), and percentage correct. While all these statistics vary across base rate and cutoff points, some vary more than others: RIOC varies across cutoff points more than MCR, MCR more than Φ, and Φ more than γ. Researchers comparing such statistics across studies need be wary of the dangers of ignoring such variation.

Practice-based interventions.

Current evidence indicates there remains a large gap in the provision of depression care, particularly in primary care. Several studies have demonstrated that interventions based on the chronic disease management model can improve patient outcomes. Challenges include designing more robust interventions that can move easily into a wide variety of primary care organizations. More research is needed to develop programs to improve outcomes for children with depression and adults with bipolar disorders.

Preparation and purification of antibodies specific to human neuronal voltage-dependent calcium channel subunits.

Neuronal voltage-dependent calcium channels (VDCCs) each comprising of alpha 1, alpha 2 delta, and beta subunits, are one mechanism by which excitable cells regulate the flux of calcium ions across the cell membrane following depolarisation Studies have shown the expression of several alpha 1 and beta subtypes within neuronal tissue. The comparative distribution of these in normal human brain is largely unknown. The aim of this work is to prepare antibodies directed specifically to selected subunits of human neuronal VDCCs for use in biochemical and mapping studies of calcium channel subtypes in the brain. Previous studies have defined DNA sequences specific for each subunit Comparison of these sequences allows the selection of unique amino acid sequences for use as immunogens which are prepared as glutathione-S-transferase (GST) fusion proteins in E. coli. Polyclonal antibodies raised against these fusion proteins are purified by Protein A chromatography, followed by immunoaffinity chromatography and extensive adsorptions using the appropriate fusion protein-GST Sepharose 4B columns. The resultant antibodies are analysed for specificity against the fusion proteins by ELISA, and by immunofluorescence and Western immunoblot analysis of recombinant HEK293 cells stably transfected with cDNAs encoding alpha 1, alpha 2 delta and beta subunits.

Children and adolescents.

Until the 2001 Surgeon Generals report there had been no acknowledgment of the need for a national plan for research priorities to improve services and reduce illness burden for children and adolescents with severe mental disorders. Barriers to services among those in need include individual and family factors, and clinician and service system factors. Additionally, little reserch is available on the impact of major policy reforms on childrens ability to obtain efficacious care. Critical research gaps exist in a number of areas with the prevention and early intervention area representing a particularly important missed opportunity.