Experience and expectations of patients on weight loss: The Learning Health System Network Experience.

OBJECTIVE: Weight perception and degree of confidence in achieving healthy lifestyle can be determinants of engagement in obesity interventions. This study explored patients' perceived need for weight loss and the degree of self-confidence in ability to lose weight and sought to identify factors associated with patients' self-confidence in ability to lose weight. METHODS: The authors analysed data from a survey mailed to primary care patients within five sites of the Learning Health Systems Network that explored participants' prior experience with weight management. RESULTS: Among the 2,263 participants who completed the survey section on 'Patients' Experience with Weight Management', perceived need to lose 51 lb or more was statistically significant among those with class III obesity compared with other body mass index (BMI) groups (p value < 0.001). Reported desire to lose weight was also significantly higher among those with the highest BMI than those who were overweight (p value < 0.001). However, this same group had the lowest belief in ability to lose weight (p value < 0.001). In a multiple regression analysis, female gender, higher BMI and need to lose >10 lb were each independently associated with less belief in being able to lose weight. CONCLUSIONS: Patients had varying perceptions on weight loss; those with category III obesity had the highest desire to lose weight but had the least confidence in ability to lose weight. Higher BMI, female gender and need to lose >10 lb were associated with decreased self-confidence in ability to lose weight.

Remission of obesity among a nationally representative sample of US children.

BACKGROUND: Little is known about the incidence and natural history of obesity remission among children outside of weight loss programmes. OBJECTIVES: The objectives are to characterize and identify sociodemographic and early life predictors of obesity remission between kindergarten and eighth grade among a nationally representative sample of US children. METHODS: The sample included children with obesity [age-specific and gender-specific body mass index percentile (BMI) ≥95] at the spring kindergarten assessment of the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99. Weight categories across 8 years of follow-up were used to identify three transition patterns: persistent obesity remission, non-persistent obesity remission and non-remission. Weight, height and BMI changes between remission categories were examined and predictors of persistent remission were identified. RESULTS: One-third of children with obesity in kindergarten experienced remission during follow-up and 21.6% of children experienced persistent remission through eighth grade. Female gender and high socio-economic status predicted persistent remission; these associations were attenuated after accounting for baseline BMI. Children experiencing persistent remission gained less weight across waves than those experiencing non-remission. CONCLUSIONS: A meaningful proportion of young children with obesity experience remission by eighth grade. Further study is needed to identify factors that support obesity remission among children outside of treatment contexts.

Interrelationships of child appetite, weight and snacking among Hispanic preschoolers.

BACKGROUND: Snacking among US preschoolers has increased in recent decades, raising questions about whether snacking contributes to dietary excess. OBJECTIVES: This research aimed to characterize snacking contributions to dietary excess and to evaluate associations with appetite and weight among preschool-aged children. METHODS: This study is a cross-sectional, observational study of 187 Hispanic low-income preschoolers. Three 24-h dietary recalls were used to assess snacking frequency and parameters of dietary excess including energy, saturated fat, trans fats and added sugars. Parental reports of child satiety responsiveness, food responsiveness, and enjoyment of food were obtained. Child height and weight were measured. RESULTS: Children consumed 28% (395 kcal) of daily energy from snacks eaten at 2.3 ± 1.0 occasions per day. Greater snacking frequency was associated with greater daily intakes of energy (p < 0.05) and added sugars (p < 0.001). Among overweight/obese children, higher enjoyment of food was associated with more frequent snacking and greater energy intake from snacks (p = 0.01). Inverse associations of enjoyment of food with snacking frequency and energy intake were seen among normal weight children (p < 0.05). CONCLUSIONS: More frequent snacking among low-income Hispanic preschoolers may contribute to excessive intakes of energy and added sugars, particularly among overweight/obese children with greater motivation to eat.

Cardio-metabolic risk screening among adolescents: understanding the utility of body mass index, waist circumference and waist to height ratio.

BACKGROUND: Few studies have assessed how well body mass index (BMI), waist circumference (WC), or waist to height ratio (WtHR) perform in identifying cardio-metabolic risk among youth. OBJECTIVE: The objective of this study was to evaluate the utility of BMI and WC percentiles and WtHR to distinguish adolescents with and without cardio-metabolic risk. METHODS: A cross-sectional analysis of data from 6097 adolescents aged 10-13 years who participated in the HEALTHY study was conducted. Receiver operating characteristic curves determined the discriminatory ability of BMI and WC percentiles and WtHR. RESULTS: The discriminatory ability of BMI percentile was good (area under the curve [AUC] ≥ 0.80) for elevated insulin and clustering of ≥3 risk factors, with optimal cut-points of 96 and 95, respectively. BMI percentile performed poor to fair (AUC = 0.57-0.75) in identifying youth with the majority of individual risk factors examined (elevated glucose, total cholesterol, low-density lipoprotein, blood pressure, triglycerides and high-density lipoprotein). WC percentile and WtHR performed similarly to BMI percentile. CONCLUSIONS: The current definition of obesity among US children performs well at identifying adolescents with elevated insulin and a clustering of ≥3 cardio-metabolic risk factors. Evidence does not support WC percentile or WtHR as superior screening tools compared with BMI percentile for identifying cardio-metabolic risk.

Relationships between the family environment and school-based obesity prevention efforts: can school programs help adolescents who are most in need?

Identifying factors that contribute to students' behavior and weight improvements during school-based obesity prevention interventions is critical for the development of effective programs. The current study aims to determine whether the support and resources that adolescent girls received from their families were associated with improvements in physical activity (PA), television use, dietary intake, body mass index (BMI) and body composition during participation in New Moves, a school-based intervention to prevent obesity and other weight-related problems. Adolescent girls in the intervention condition of New Moves (n = 135), and one parent of each girl, were included in the current analysis. At baseline, parents completed surveys assessing the family environment. At baseline and follow-up, 9-12 months later, girls' behaviors were self-reported, height and weight were measured by study staff and body fat was assessed using dual-energy X-ray absorptiometry. Results showed few associations between family environment factors and girls' likelihood of improving behavior, BMI or body composition. These findings suggest that in general, school-based interventions offer similar opportunities for adolescent girls to improve their PA, dietary intake, and weight, regardless of family support.

Use of statistical process control for surveillance of pulmonary dysfunction in groups in the workplace.

Workplace surveillance is an essential feature of an effective occupational health program. Unfortunately, many health care organizations are beginning to collect large quantities of clinical information without much thought to subsequent application. In this paper, we propose a screening technique to help manage this situation. Specifically, we advocate "control charts for fraction non-conforming" for use in the medical surveillance of work areas. A military installation in the mid-western United States with 63 work areas is analyzed using up to seven years worth of spirometry data. Based on the results of 6 separate tests, a classification of normal or abnormal was made for each individual and the percent of abnormalities by area and year was calculated. The results were analyzed via control charts and contrasted to a preset percentage method. Cigarette smoking was then controlled for in the analysis to account for abnormalities that may be occupationally related versus personal habits. We demonstrate the utility of control charts for the compact display of surveillance data and show how it can aid in the analysis of an extremely complex health care concern. A recommendation is made for managing a surveillance program using spirometry and control charts and supported by follow-on investigation of two areas flagged as abnormal by the procedure.

Optimization of adaptive-optics systems closed-loop bandwidth settings to maximize imaging-system performance.

We present the results of research aimed at optimizing adaptive-optics closed-loop bandwidth settings to maximize imaging-system performance. The optimum closed-loop bandwidth settings are determined as a function of target-object light levels and atmospheric seeing conditions. Our work shows that, for bright objects, the optimum closed-loop bandwidth is near the Greenwood frequency. However, for dim objects without the use of a laser beacon the preferred closed-loop bandwidth settings are a small fraction of the Greenwood frequency. In addition, under low light levels selection of the proper closed-loop bandwidth is more critical for achieving maximum performance than it is under high light levels. We also present a strategy for selecting the closed-loop bandwidth to provide robust system performance for different target-object light levels.

Selecting optimal experiments for multiple output multilayer perceptrons.

Where should a researcher conduct experiments to provide training data for a multilayer perceptron? This question is investigated, and a statistical method for selecting optimal experimental design points for multiple output multilayer perceptrons is introduced. Multiple class discrimination problems are examined using a framework in which the multilayer perceptron is viewed as a multivariate nonlinear regression model. Following a Bayesian formulation for the case where the variance-covariance matrix of the responses is unknown, a selection criterion is developed. This criterion is based on the volume of the joint confidence ellipsoid for the weights in a multilayer perceptron. An example is used to demonstrate the superiority of optimally selected design points over randomly chosen points, as well as points chosen in a grid pattern. Simplification of the basic criterion is offered through the use of Hadamard matrices to produce uncorrelated outputs.

Image-quality metrics for characterizing adaptive optics system performance.

Adaptive optics system (AOS) performance is a function of the system design, seeing conditions, and light level of the wave-front beacon. It is desirable to optimize the controllable parameters in an AOS to maximize some measure of performance. For this optimization to be useful, it is necessary that a set of image-quality metrics be developed that vary monotonically with the AOS performance under a wide variety of imaging environments. Accordingly, as conditions change, one can be confident that the computed metrics dictate appropriate system settings that will optimize performance. Three such candidate metrics are presented. The first is the Strehl ratio; the second is a novel metric that modifies the Strehl ratio by integration of the modulus of the average system optical transfer function to a noise-effective cutoff frequency at which some specified image spectrum signal-to-noise ratio level is attained; and the third is simply the cutoff frequency just mentioned. It is shown that all three metrics are correlated with the rms error (RMSE) between the measured image and the associated diffraction-limited image. Of these, the Strehl ratio and the modified Strehl ratio exhibit consistently high correlations with the RMSE across a broad range of conditions and system settings. Furthermore, under conditions that yield a constant average system optical transfer function, the modified Strehl ratio can still be used to delineate image quality, whereas the Strehl ratio cannot.

HIS: shouldn't they make hospitals more effective, efficient providers of care?

Computer systems ought to make hospitals run more smoothly, but the ideal sometimes doesn't jibe with the reality. One hospital CEO reminds the industry that form should follow function.