Robust estimation and design procedures for the random effects model

The authors discuss two robust estimators for estimating variance components in the random effects model, and they obtain finite‐sample breakdown points for the estimators. Based on the finite‐sample breakdown point, they propose a criterion for selecting robust designs. With robust designs, one can get efficient and reliable estimates for variance components regardless of outliers which may happen in the experiment. The authors give examples to show the performance of robust estimators and to compare robust designs with optimal designs based on the traditional analysis of variance estimation method.     

Older women on the U.S.-Mexico border: exploring the health of Hispanics and non-Hispanics Whites

Research on ethnicity and socioeconomic status (SES) suggests that Hispanics are more likely than non-Hispanic Whites to experience poverty and low levels of education, which may relate to poorer health status. This study used a health survey to examine income, education, ethnicity, birthplace, and age on self-reported health factors of women age 60 and older on the U.S.-Mexico border. Results show that income, age, and education were significantly associated with several health factors (Physical Health, Emotional Health, General Health, Energy Level, and Activity Potential). Older women with lower SES, regardless of ethnicity, reported poorer health than younger-old women with higher SES.     

Parental views of in-home services: what predicts satisfaction with child welfare workers?

Evidence on client satisfaction deserves consideration in the design of child welfare policies, programs, and practices. Data in this study come from the National Survey of Child and Adolescent Well-Being. Clients receiving in-home services reported moderate levels of satisfaction with their child welfare workers. Caregiver reports of having less than two child welfare workers, having more recent contact, and receiving timely, responsive services were associated with higher perceived quality of relationships with child welfare workers. The child welfare workers' reports of cooperativeness by the caregiver were also associated with higher caregiver-reported relationship quality.     

Infant mortality decline in Malaysia, 1946–1975: The roles of changes in variables and changes in the structure of relationships

This analysis has identified several factors contributing to the dramatic decline in infant mortality since World War II in Malaysia, as well as one factor that prevented the infant mortality rate from declining even more rapidly. Our main findings are the following: On average, mothers' education more than doubled over the study period, contributing to the decline in their infants' mortality. In addition, the beneficial effect of mothers' education on infant survival appears to have become stronger over the study period. Hence, further advances in education should lead to further improvements in infants' survival prospects. Another analysis of these data (Peterson et al. 1985) found that education is somewhat more influential in affecting child mortality in low-mortality, high-income areas than in the opposite type of areas. Therefore, socioeconomic development may have complemented, instead of substituted for, the the beneficial effect of mothers' education in promoting infant and child survival in Malaysia. Improvements in water and sanitation also contributed to the infant mortality decline, especially for babies who did not breastfeed. However, unlike education, these influences have become less important over time, especially for babies who are not breastfed. Hence, further improvements in water and sanitation, a goal of Malaysia's Rural Environmental Sanitation Programme, may have smaller relative effects on infant mortality than did previous improvements. Targeting such improvements on areas where women breastfeed little or not at all, however, will increase their effectiveness in promoting infant survival. The substantial reductions in breastfeeding that have taken place since World War II have kept the infant mortality rate in Malaysia from declining as rapidly as it would have otherwise. We estimate that, in our sample, the detrimental effects on infant survival of the decline in breastfeeding have more than offset the beneficial effects of improvements in water and sanitation. Unlike some other researchers (e.g., Palloni 1981), we find that changes in fertility levels and in the timing and spacing of births have had negligible effect in explaining the decline in infant mortality within the samples we have considered. We have excluded births to older women from our analysis, however; this exclusion may have led to an understatement of the influence of changes in the age pattern of childbearing.(ABSTRACT TRUNCATED AT 400 WORDS)     

Modeling Event Times with Multiple Outcomes Using the Wiener Process with Drift

Length of stay in hospital (LOS) is a widely used outcome measure in Health Services research, often acting as a surrogate for resource consumption or as a measure of efficiency. The distribution of LOS is typically highly skewed, with a few large observations. An interesting feature is the presence of multiple outcomes (e.g. healthy discharge, death in hospital, transfer to another institution). Health Services researchers are interested in modeling the dependence of LOS on covariates, often using administrative data collected for other purposes, such as calculating fees for doctors. Even after all available covariates have been included in the model, unexplained heterogeneity usually remains. In this article, we develop a parametric regression model for LOS that addresses these features. The model is based on the time, T, that a Wiener process with drift (representing an unobserved health level process) hits one of two barriers, one representing healthy discharge and the other death in hospital. Our approach to analyzing event times has many parallels with competing risks analysis (Kalbfleisch and Prentice, The Statistical Analysis of Failure Time Data, New York: John Wiley and Sons, 1980)), and can be seen as a way of formalizing a competing risks situation. The density of T is an infinite series, and we outline a proof that the density and its derivatives are absolutely and uniformly convergent, and regularity conditions are satisfied. Expressions for the expected value of T, the conditional expectation of T given outcome, and the probability of each outcome are available in terms of model parameters. The proposed regression model uses an approximation to the density formed by truncating the series, and its parameters are estimated by maximum likelihood. An extension to allow a third outcome (e.g. transfers out of hospital) is discussed, as well as a mixture model that addresses the issue of unexplained heterogeneity. The model is illustrated using administrative data.     

Low back pain in physical therapists: a cultural approach to analysis and intervention

Low back pain is one of the most prevalent work related injuries in the physical therapy profession. New graduates and therapists working in rehabilitation and acute care hospitals are at the highest risk for developing low back pain [9]. Although physical therapists are trained in maintaining proper body mechanics and preventing work related injuries, between 30% and 63% of therapists will experience low back pain at some point in their careers [2,4,9]. The culture of physical therapy is one of the primary factors contributing to this problem, with many therapists reporting that their decision to use back pain preventive strategies depends on their colleagues' use of these strategies. The authors will use Green and Kreuter's PRECEDE-PROCEED model to identify behavioral, environmental, educational and ecological factors contributing to the problem; then will propose a health promotion intervention using the social action theory at the community level to decrease work-related low back pain in physical therapists while simultaneously addressing the culture of physical therapy.     

Effectively addressing mental health issues in child welfare practice. Introduction

This volume is dedicated to advances in policies, programs, and practices for effectively addressing the mental health issues in child welfare practice, and it reflects CWLA's and the Mental Health Advisory Board's commitment to ensuring children and their families receive effective mental health services that lead to their optimal well-being.