A Meta-Analysis of Children's Hand-to-Mouth Frequency Data for Estimating Nondietary Ingestion Exposure

Because of their mouthing behaviors, children have a higher potential for exposure to available chemicals through the nondietary ingestion route; thus, frequency of hand-to-mouth activity is an important variable for exposure assessments. Such data are limited and difficult to collect. Few published studies report such information, and the studies that have been conducted used different data collection approaches (e.g., videography versus real-time observation), data analysis and reporting methods, ages of children, locations, and even definitions of "mouthing." For this article, hand-to-mouth frequency data were gathered from 9 available studies representing 429 subjects and more than 2,000 hours of behavior observation. A meta-analysis was conducted to study differences in hand-to-mouth frequency based on study, age group, gender, and location (indoor vs. outdoor), to fit variability and uncertainty distributions that can be used in probabilistic exposure assessments, and to identify any data gaps. Results of this analysis indicate that age and location are important for hand-to-mouth frequency, but study and gender are not. As age increases, both indoor and outdoor hand-to-mouth frequencies decrease. Hand-to-mouth behavior is significantly greater indoors than outdoors. For both indoor and outdoor hand-to-mouth frequencies, interpersonal, and intra-personal variability are approximately 60% and approximately 30%, respectively. The variance difference among different studies is much bigger than its mean, indicating that different studies with different methodologies have similar central values. Weibull distributions best fit the observed data for the different variables considered and are presented in this article by study, age group, and location. Average indoor hand-to-mouth behavior ranged from 6.7 to 28.0 contacts/hour, with the lowest value corresponding to the 6 to <11 year olds and the highest value corresponding to the 3 to <6 month olds. Average outdoor hand-to-mouth frequency ranged from 2.9 to 14.5 contacts/hour, with the lowest value corresponding to the 6 to <11 year olds and the highest value corresponding to the 6 to <12 month olds. The analysis highlights the need for additional hand-to-mouth data for the <3 months, 3 to <6 months, and 3 to <6 year age groups using standardized collection and analysis because of lack of data or high uncertainty in available data. This is the first publication to report Weibull distributions as the best fitting distribution for hand-to-mouth frequency; using the best fitting exposure factor distribution will help improve estimates of exposure. The analyses also represent a first comprehensive effort to fit hand-to-mouth frequency variability and uncertainty distributions by indoor/outdoor location and by age groups, using the new standard set of age groups recommended by the U.S. Environmental Protection Agency for assessing childhood exposures. Thus, the data presented in this article can be used to update the U.S. EPA's Child-Specific Exposure Factors Handbook and to improve estimates of nondietary ingestion in probabilistic exposure modeling.     

Effect of urbanization on surface water chemistry in south-central Texas

The use of state factors can adequately describe the biogeochemistry and geochemistry of relatively undisturbed surface waters. Watersheds with increasing proportions of urban and suburban land use, particularly in sub-tropical, semi-arid and arid urban areas, that utilize irrigation for turfgrass and landscaping may have a low flow urban signature that relates to the source water used by municipal water suppliers. We examined thirteen watersheds; four with waste water treatment plants (24–67% urbanization), four rural (< 30% urbanization) and five urban (> 30% urbanization) in a humid sub-tropical oak savannah in south-central Texas. Three of our urban and one of our rural watersheds displayed the signature of municipal tap water. Three out of four watersheds with waste water treatment plants displayed the signature of treated sewage effluent. We suggest as a result of this study that the chemistry of municipal tap water particularly that with high sodium and bicarbonate, used in urban watersheds for irrigating turfgrass and landscapes may have detrimental effects on base flow stream water quality after it has interacted with watershed soils.     

The Norway Couple Project: Lessons Learned

Couple therapists in routine practice may find it difficult to apply findings from an increasingly expanding and complex body of couple therapy research. Meanwhile, concerns have been raised that competency in evidence‐based treatments is insufficient to inform many practice decisions or ensure positive treatment outcomes (American Psychological Association Presidential Task Force on Evidence‐Based Practice, American Psychologist, 2006, 271). This article aims to narrow the research/practice gap in couple therapy. Results from a large, randomized naturalistic couple trial (Anker, Duncan, & Sparks, Journal of Consulting and Clinical Psychology, 2009, 693) and four companion studies are translated into specific guidelines for routine, eclectic practice. Client feedback, the therapeutic alliance, couple goals assessment, and therapist experience in couple therapy provide a research‐informed template for improving couple therapy outcomes.     

Underreporting of abortion in surveys of U.S. women: 1976 to 1988

Although research on reproductive behavior depends heavily on information from surveys, abortions are characteristically underreported in such data. Estimates of the level of reporting are made for each of the recent major surveys of U.S. women: the 1976, 1982, and 1988 cycles of the National Survey of Family Growth, the 1976 and 1979 National Surveys of Young Women, and the National Longitudinal Surveys of Work Experience of Youth. The estimates are based on comparisons with external counts of abortions taking place. We examine variation by characteristics of women, trends over time, and the possible effects of length of recall and of the way in which questions about abortion are asked. Abortion reporting is found to be highly deficient in all the surveys, although the level varies widely. Whites are more likely to report their abortions than nonwhites. Special, confidential questioning procedures hold promise for improving the results.     

A systematic review of psychosocial interventions for suicidal adolescents

Suicide is a leading cause of death for young people and rates of serious suicidal thoughts are even higher. Due to these high rates and potential harm to youth, effective interventions are necessary. The purpose of this systematic review was to determine the impact of interventions designed for suicidal adolescents. Both quasi-experimental and experimental designs in the published and unpublished literature were included, and a total of 17 studies were located. According to meta-analysis, intervention group participants were slightly less likely to have suicidal and self-harm events than control group participants. However, when studies assessed outcome at a later period than immediately after intervention, experimental group participants were slightly more likely to have suicidal and self-harm events than control group participants. For studies that measured suicidal ideation at posttest, intervention group participants were slightly less likely to report suicidal ideation than control group participants, both at posttest and at follow-up. These contradictory findings are explored and discussed.     

Managing Perishables with Time and Temperature History

We address the use and value of time and temperature information to manage perishables in the context of a retailer that sells a random lifetime product subject to stochastic demand and lost sales. The product's lifetime is largely determined by the temperature history and the flow time through the supply chain. We compare the case in which information on flow time and temperature history is available and used for inventory management to a base case in which such information is not available. We formulate the two cases as Markov Decision Processes and evaluate the value of information through an extensive simulation using representative, real world supply chain parameters.     

Competition and Wage Discrimination: The Effects of Interindustry Concentration and Import Penetration*

Objective. Economic theory suggests that competition reduces employers' latitude to engage in wage discrimination ( Becker, 1957 ). This study investigates the impact of foreign and domestic competition on wage discrimination. Method. Utilizing the sample of males in U.S. manufacturing industries from the 1990 Public Use Micro Sample (PUMS), industry wage equations are estimated. In a second stage, the impact of domestic and foreign competition on racial wage disparity is assessed. Results. We find little evidence to support our hypothesis. Conclusions. Notwithstanding, the failure of conventional economic theory to satisfactorily explain racial wage disparity reiterates the need to incorporate alternative theories of discrimination into mainstream economic theory.     

Variable subset selection for optimal regression prediction at a specified point

It is often desirable to select a subset of regression variables so as to maximise the accuracy of prediction at a pre-specified point. There are a variety of possible mean-square-error-type criteria which could be used to measure the accuracy of prediction and hence to select an optimal subset. We shall show how these can easily be included in existing stepwise regression codes. The performance of the criteria is compared on a data set, where it becomes obvious that not only do different criteria give rise to different subsets at the same prediction point, but the same criterion quite commonly gives rise to different subsets at different prediction points. Thus the choice of a criterion has a major effect on the subset selected, and so requires conscious selection.     

Parent and Child Therapy: An Attachment‐Based Intervention for Children With Challenging Problems

Parent and Child Therapy (PACT) is an attachment‐based intervention for children aged between 4 and 12 years old experiencing emotional and behavioural problems. It is appropriate for distressed parent—child relationships which have not responded to systemic family therapy. PACT seeks to reframe parent—child relationship distress using narrative techniques and experiential tasks based on the concept of supported looking. Therapy occurs in parallel for parent and child using a one‐way screen. PACT improves parents' reflective capacity and sensitivity, and for the child's sense of security in her primary attachment relationship. An outline of the four stages of PACT is presented along with a case study to illustrate the course of PACT. Finally, we discuss the dissemination of PACT within a busy child and adolescent mental health service and outline our plans for future outcome evaluation.