Mean Number Of Elements Research Articles

Establishing a Baseline Measure of School Wellness-Related Policies Implemented in a Nationally Representative Sample of School Districts

The Child Nutrition and WIC Reauthorization Act of 2004 required school districts to establish a local school wellness policy by the first day of the 2006-2007 school year. To provide a baseline measure of the extent to which wellness-related policies were implemented in school districts nationwide in 2006, this study analyzed data from the 2006 School Health Policies and Programs Study (SHPPS). SHPPS used a cross-sectional design to measure policies and practices among a nationally representative sample of 538 public school districts. The authors applied a standardized wellness policy coding system to the data by matching each element to relevant questions from SHPPS and calculated the percentage of school districts meeting each element in the coding system. Statistical analyses included calculation of 95% confidence intervals for percentages and mean number of elements met in each area. In 2006, none of the districts met all elements included in the coding system for local wellness policies. In addition, the percentage of districts meeting each element varied widely. On average, districts met the greatest number of elements in the area of nutrition education and the least number of elements in the area of physical activity. By applying a coding system for district policies to an existing dataset, this study used a novel approach to determine areas of strength and weakness in the implementation of local school wellness-related policies in 2006.

Brachial plexopathy in gunshot wounds and motor vehicle accidents: Comparison of electrophysiologic findings

Objective: To characterize the extent and degree of severity in subjects with gunshot wounds (GSWs) to the brachial plexus and to investigate the association between type of injuries and the predominant level involved. Design: A cross-sectional, retrospective review of electrophysiologic data. Setting: Electromyography laboratory of a county hospital. Patients: Thirty consecutive patients with GSWs and 14 patients with traction brachial plexopathies during a 5-year period (1992 through 1996). Main Outcome Measures: The injury was categorized according to the level predominantly involved, and each component of the four major levels of the plexus was analyzed. The association between type of injury and predominant level involved was assessed via two-tailed χ 2 test. The mean number of elements per subject to each level involved was compared between GSW and motor vehicle accident (MVA) patients using unpaired t test. Results: The type of injury (GSW vs MVA) is significantly associated with the level involved. GSWs were implicated in infraclavicular rather than supraclavicular injury. Compared with MVA, the GSW plexopathies had significant lower mean number of components involved at the root and cord levels, but higher at the terminal nerve branches of plexus. In GSWs, nearly two thirds of all components were severely injured and 60% were completely damaged. Conclusion: These findings demonstrate that gunshot plexopathies are characterized with multielement distribution and a mixture of lesions with or without continuity.