Clustering in surgical trials : database of intracluster correlations

PMID: 22217216 [PubMed - indexed for MEDLINE] PMCID: PMC3311136 Free PMC ArticlePeer reviewedPublisher PD

Perceptions of the food shopping environment are associated with greater consumption of fruits and vegetables

Objective The present study examined whether characteristics such as quality, selection and convenience are associated with dietary intake of fruits and vegetables independent of perceived costs in an inner-city, low-income population. Design Secondary analysis of baseline data from a social marketing intervention designed to change household dietary practices among parents of 3- to 7-year-old children. Setting A community sample drawn from six low-income, primarily minority neighbourhoods in Chicago, IL, USA. Subjects From the parent study, 526 respondents completed the baseline survey and were eligible for inclusion. Of this number, 495 provided complete data on sociodemographic characteristics, fruit and vegetable consumption, perceptions of the shopping environment, perceived costs of fruits and vegetables, and food shopping habits. Results Logistic regression analysis showed that more positive perceptions of the food shopping environment were associated with greater consumption of fruits and vegetables. There was an increase of approximately twofold in the likelihood of consuming three or more fruits and vegetables daily per level of satisfaction ascribed to the shopping environment. This association was independent of perceived cost, store type and sociodemographic characteristics. Conclusions Our data show that among a generally minority and low-income population, quality, selection and convenience are important determinants of fruit and vegetable consumption. Nutrition promotion campaigns that aim to alter the built environment by increasing access to fruits and vegetables should recognize that simply increasing availability may not yield beneficial change when characteristics of the shopping context are ignored

Differential effects of parental controls on adolescent substance use:for whom is the family most important?

Objective Social control theory assumes that the ability of social constraints to deter juvenile delinquency will be invariant across individuals. This paper tests this hypothesis and examines the degree to which there are differential effects of parental controls on adolescent substance use. Methods Analyses are based on self-reported data from 7,349 10th-grade students and rely on regression mixture models to identify latent classes of individuals who may vary in the effects of parental controls on drug use. Results All parental controls were significantly related to adolescent drug use, with higher levels of control associated with less drug use. The effects of instrumental parental controls (e.g., parental management strategies) on drug use were shown to vary across individuals, while expressive controls (e.g., parent/child attachment) had uniform effects in reducing drug use. Specifically, poor family management and more favorable parental attitudes regarding children’s drug use and delinquency had stronger effects on drug use for students who reported greater attachment to their neighborhoods, less acceptance of adolescent drug use by neighborhood residents, and fewer delinquent peers, compared to those with greater community and peer risk exposure. Parental influences were also stronger for Caucasian students versus those from other racial/ethnic groups, but no differences in effects were found based on students’ gender or commitment to school. Conclusions The findings demonstrate support for social control theory, and also help to refine and add precision to this perspective by identifying groups of individuals for whom parental controls are most influential. Further, they offer an innovative methodology that can be applied to any criminological theory to examine the complex forces that result in illegal behavior