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Measurements of physical and social phenomena are often used in the decision-making process despite the error introduced by human and context variation. It would be advantageous to a decision maker to know the sources and magnitudes of such errors in using a measurement system or in choosing among alternative measurement systems. This paper describes an approach to determining the reliability of a measurement procedure called generalizability (G) theory. G theory uses the results of a random-effects analysis of variance to estimate the magnitude of error variability associated with each of several potential sources. These estimates can then be used to calculate a number of indices which typify the amount of precision provided by a measurement system in a particular context of usage. The major concepts of G theory are described and illustrated in the context of evaluating a radiologic total lung capacity measurement system. [ABSTRACT FROM AUTHOR]

Technical innovations may produce not only the chances they were intended to effect but also lead to consequences which are unexpected and sometimes destructive. There is an intimate relation between technological innovation and political power. Any great advances in reproductive technology are very likely to be controlled and commandeered by the state with all kinds of unforeseeable consequences. [ABSTRACT FROM PUBLISHER]

Aims: This study explored the reliability, validity and perceived comfort of a novel thumb pressure measure and calculation of a toe-thumb index to identify their suitability as an adjunct or alternatives to ankle-brachial and toe-brachial indices., Methods and Results: Repeated manual thumb and toe systolic blood pressures were conducted using two raters, over two time points, on 34 healthy participants. Concurrent automated toe, thumb and brachial systolic blood pressures as well as comfort ratings for these measures (using a 10 mm visual analogue scale) were captured once by a research assistant. Automated thumb and brachial measures showed fair correlation (ρ = 0.36, p = 0.03) and a toe-thumb index and toe-brachial index good correlation (ρ = 0.62, p < 0.01). Intraclass correlation coefficients (ICC) identified moderate intra-rater reliability for manual thumb pressures for Rater 1 and 2 (ICC 0.57, 95% CI [0.14, 0.79] and ICC 0.74, 95% CI [0.49, 0.87], respectively), while inter-rater reliability was poor (ICC = 0.16, 95% CI [-0.85, 0.47]). Concurrent validity comparing manual and automated measures for thumb pressure was also poor (ICC -0.05, 95% CI [-1.06, 0.72] and ICC 0.42, 95% CI [-0.16, 0.72] Rater 1 and 2 respectively). Thumb measures were significantly more comfortable than brachial measures (5 mm, p < 0.00)., Conclusion: Thumb systolic pressures are correlated with brachial systolic pressures, with reasonable intra-rater reliability, however, correlation is only fair and measurement error wider than clinically acceptable. Furthermore, manual measures are poorly correlated with automated units. Consequently, caution is required in applying these techniques. As thumb measures were perceived as significantly more comfortable than brachial measures and have an advantage where brachial pressures cannot, or should not, be obtained, further evaluation is warranted., (© 2024 The Author(s). Journal of Foot and Ankle Research published by John Wiley & Sons Australia, Ltd on behalf of Australian Podiatry Association and The Royal College of Podiatry.)

Background: COVID-19 revealed and broadened existing disparities in large cities. This article interprets the early impacts of COVID-19 on food insecurity (FI) in the Chicago and New York City (NYC) metropolitan areas for Black, Indigenous, and People of Color (BIPOC) and provides a study using a Social Determinants of Health (SDOH) framework., Methods: A cross-sectional survey adapted from the National Food Access and COVID Research Team (NFACT) was deployed in Chicago (N = 680) and in NYC (N = 525) during summer 2020 and oversampled for race, ethnicity, and socioeconomic status. Multivariate binary logistic regression generated adjusted odds ratios (aOR) and 95% CIs for FI and select SDOH variables, which was conducted on each dataset., Results: The prevalence of FI in NYC increased to 66.8% (from 57.8%) and in Chicago to 44.8% (from 41.0%). While higher income protected against FI before, protection was diminished or eliminated since COVID-19. FI declined for households with children in NYC while odds increased and became significant in Chicago. Respondents with chronic health conditions experienced increased odds of FI since COVID. In Chicago, this variable had the highest odds of FI. Respondents with depression or anxiety had increased odds of FI. In NYC, depression had the highest odds of FI. Females in NYC were protected against FI. Hispanics in NYC lost protection against FI from before to since COVID-19., Conclusions: Results support the observed rise of FI for BIPOC and its association with health status. The analysis has multifaceted, structural policy implications for reducing FI in urban centers., (© 2022. W. Montague Cobb-NMA Health Institute.)

Background: The coronavirus disease 2019 (COVID-19) pandemic profoundly affected food systems including food security. Understanding how the COVID-19 pandemic impacted food security is important to provide support and identify long-term impacts and needs., Objective: The National Food Access and COVID research Team (NFACT) was formed to assess food security over different US study sites throughout the pandemic, using common instruments and measurements. This study presents results from 18 study sites across 15 states and nationally over the first year of the COVID-19 pandemic., Methods: A validated survey instrument was developed and implemented in whole or part through an online survey of adults across the sites throughout the first year of the pandemic, representing 22 separate surveys. Sampling methods for each study site were convenience, representative, or high-risk targeted. Food security was measured using the USDA 6-item module. Food security prevalence was analyzed using ANOVA by sampling method to assess statistically significant differences., Results: Respondents ( n  = 27,168) indicate higher prevalence of food insecurity (low or very low food security) since the COVID-19 pandemic, compared with before the pandemic. In nearly all study sites, there is a higher prevalence of food insecurity among Black, Indigenous, and People of Color (BIPOC), households with children, and those with job disruptions. The findings demonstrate lingering food insecurity, with high prevalence over time in sites with repeat cross-sectional surveys. There are no statistically significant differences between convenience and representative surveys, but a statistically higher prevalence of food insecurity among high-risk compared with convenience surveys., Conclusions: This comprehensive study demonstrates a higher prevalence of food insecurity in the first year of the COVID-19 pandemic. These impacts were prevalent for certain demographic groups, and most pronounced for surveys targeting high-risk populations. Results especially document the continued high levels of food insecurity, as well as the variability in estimates due to the survey implementation method., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.)

The theory and measurement of the social determinants of health featured in a three-part seminar series on Social Determinants of Health, Law and Policy held at the Taubman Center for Public Policy, Brown University in February 2012. The seminar series represents a broader commitment to engage the public, health providers, researchers, and policy makers in dialogue for the purposes of identifying and addressing social determinants of health at community and state levels. This article summarizes and expands upon the first part of the series by defining social determinants of health and exploring methodological debates over their measurement, with a focus on income inequality, racism and discrimination, housing security, and food security. The authors of this article and the members of the seminar series represent the kind of interdisciplinary and applied work necessary for addressing the five key areas of social determinants of health identified in Healthy People 2020: economic stability, education, social and community context, health and health care, and neighborhood and environment.

The difficulties of achieving successful collaboration between stakeholders can lead to uncoordinated and fragmented outcomes for HIV/AIDS programming, which has consequences for the immediate health and livelihood security of the intended beneficiaries. This article examines the collaboration between local, national and international partner organisations in the delivery of and coordination of HIV/AIDS home-based care in Zimbabwe. The purpose of the research was to provide an external assessment of home-based care and to identify the problems that impede the delivery of health resources. Fieldwork was conducted between 2005 and 2008 at rural and peri-urban locations in Zimbabwe, using a combination of informal interviews, focus groups and participant observation. The findings suggest that the delivery of healthcare is impeded by problematic relationships between programme stakeholders-government, non-governmental and community-based. The outcome of poor service delivery is demonstrated to have a direct negative impact on the access to services, quality of care, and health outcomes for programme participants. The methods and findings of this research highlight the use of rapid ethnographic appraisal by social scientists to represent the interests of HIV/AIDS-affected populations in programme and policy design. This approach is crucial in situations such as in Zimbabwe where beneficiaries are less willing to voice their opinions for fear of being cut off from what little assistance is available in case what they say is viewed as uncooperative or noncompliant with a programme's objectives. The findings question the widely held assumption that multisectoral relationships are the most efficient way to deliver services.

This paper analyzes the dynamics of cell proliferation in the developing central nervous system. Three different algorithms, Fano factor, Allan factor and detrended fluctuations analysis, are used to estimate de scaling exponent of space numerical series obtained by recording the number and position of proliferating cells along the cephalic-caudal axis of the system. It can be concluded that the dynamics of proliferation involves two component: (a) a random noncorrelated stochastic component representing a basal proliferating activity uniformly distributed along the cephalic-caudal axis and (b) a deterministic nonstationary component that imposes a defined global trend to the process. The deterministic nonstationary trend can be interpreted as the effect of a controlling influence operating along the cephalic-caudal axis. This result indicates that the proliferative activity is spatially organized along the cephalic-caudal axis of the system.

Two on-line configurations using multiple 6- and 10-port valves were investigated for high-flow on-line extraction of a basic drug in rat plasma and human urine using a reversed-phase and a cation-exchange SPE sorbent. The first configuration studied was a single reversed-phase extraction cartridge (2.1 x 20 mm, 25 microm) using an optimized washing protocol. The results showed that up to 1.5 mL of sample (urine or plasma diluted 1:1) can be injected with limits of quantification (LOQs) as low as 100 pg/mL. The second configuration studied was the combination of a cation exchanger and a reversed-phase cartridge using at-column dilution. The results showed better LOQs than those obtained with the single cartridge at 10 pg/mL with the same injection volume. The mass spectrometer was operated in the multiple reaction monitoring (MRM) mode. All calibration curves gave an average of 5% relative standard deviation (RSD)., (Copyright 2002 John Wiley & Sons, Ltd.)

Several configurations using 6- and 10-port switching valves were studied for high flow, on-line extraction of rat plasma coupled to an electrospray triple quadrupole mass spectrometer. Each plasma sample was diluted 1:1 with an aqueous internal standard solution. The sample was injected into a 2.1 x 20 mm cartridge column packed with 25 microm divinylbenzene/N-vinylpyrrolidone packing using 100% aqueous mobile phase at 4 mL/min. After sample loading and sample cleanup, the analytes were eluted from the extraction column with a 1.0-min gradient at 0.4 mL/min. The samples were either analyzed directly after elution from the extraction column or after additional separation using a short high performance liquid chromatography (HPLC) column. The different configurations were tested using an acidic drug (diflunisal) and a basic drug (clemastine) in rat plasma. On-line analysis was performed by injecting 200 microL of diluted plasma. The mass spectrometer was operated in the multiple reaction monitoring (MRM) mode. All calibration standards gave relative standard deviations (RSDs) below 5%. The total time per sample was 3 min., (Copyright 2001 John Wiley & Sons, Ltd.)

Sevelamer hydrochloride is a cross-linked polymeric amine; it is the active ingredient of Renagel capsules. Renagel is indicated for the control of hyperphosphatemia in patients with end-stage renal disease. An in vitro phosphate-binding assay is required to measure the drug's efficacy. The assay developed for this purpose involves mixing the drug (polymer) with a solution of known phosphate concentration, filtering off the polymer-phosphate complex, and quantitating the unbound phosphate concentration by ion chromatography. The binding capacity, reported as mmol of phosphate bound g of polymer(-1), is calculated from the calculated amount of bound phosphate and the weight of polymer used. The method has been validated for accuracy, precision, linearity, range, and ruggedness.

A synthetic chiral surfactant was employed for the enantioselective micellar electrokinetic capillary chromatographic (MECC) separation of amino acid enantiomers derivatized with 6-aminoquinoyl-N-hydroxysuccinimidyl carbamate (AQC). The effect of surfactant concentration and buffer pH on resolution was studied, and the optimized conditions were used to evaluate the method in terms of sensitivity, reproducibility, and linearity. Resolution and alpha values for 12 ACQ-derivatized amino acids are reported. The ability to perform both achiral and chiral separations simultaneously is illustrated in a separation of a mixture of six amino acid enantiomeric pairs, all with baseline resolution. The direct reversal of enantiomer migration order, useful in quantitation and chiral identification, is also shown. Comparisons with other N-protected amino acid derivatives are made in terms of resolution and sensitivity, and the advantages of this chiral MECC technique used in conjunction with the inherent advantages of the AQC derivatizing reagent are discussed.

The recording of a fetal electrocardiogram from abdominal surface electrodes is severely obscured by additive noise. There are several sources of interference. A two-step method was used to filter the interferences. The mother's electrocardiogram is removed first. The second stage of the filter eliminates the remaining noise by means of coherent averaging techniques. These require the detection of fetal heartbeats. A detection algorithm is suggested that shows high efficiency in this environment, where signal-to-noise ratio is extremely low.

Capillary isoelectric focusing (CIEF) in uncoated and commercially available coated capillaries was applied to the separation of tryptic peptides from bovine and chicken cytochrome c. This is the first report of peptide mapping by CIEF. Before separation, the pIs of individual peptides expected to be formed during the digest were calculated, and then the separation pattern obtained was correlated with the calculated pIs. This correlation was reasonably good for some peptides, but not as good for others. However, differentiation of the two species digests was easily achieved based on the CIEF map. The major limitation of the method is the fact that uv detection at 280 nm must be employed, meaning that only tryptophan and tyrosine containing peptides will be detected, since the ampholytes used to generate the pH gradient absorb below 280 nm. Post-column derivatization of the peptides is one solution to this problem. Migration time reproducibility was on the order of 2%, and run times were less than 20 min for the entire pH gradient range in the uncoated capillary. In the coated capillary, superior resolution was obtained at the expense of longer run times.

The field of capillary electrophoresis has undergone rapid development over the past 10 years. Many advances have been made, but there are still some problems that must be addressed before the technique can reach its full potential.

Polycyclic aromatic hydrocarbons (PAHs) were oxidized with Ce(IV), and the resulting quinones were determined by reductive-mode liquid chromatography-electrochemical detection. This oxidation is a rapid, automatable step, involving of Ce(IV) reagent to the PAH sample and cleaning up the derivative with C18 solid-phase extraction. Using a C18 analytical column and a 2-propanol-phosphate buffer as the mobile phase, detection limits were in the ppb range for naphthalene, phenanthrene and anthracene, with linearity over 3-5 orders of magnitude. Method validation was performed by addition of the PAHs to tap water and determining the levels by reference to a calibration curve. The three PAHs can be simultaneously derivatized and determined under the same chromatographic conditions. Analysis of a motor-oil sample is also shown.

Strategies reported for the separation of proteins in capillary zone electrophoresis and capillary isoelectric focusing are reviewed. The strategies are grouped into two categories: coated capillaries and buffer/sample additives. Success attained with each case and also, more importantly, the limitations of the methodology are discussed. Recent results from our own laboratory in the area of capillary isoelectric focusing in uncoated, fused silica capillaries using additives are summarized. The advantages and disadvantages of coated columns vs. additives are delineated.

In two studies Ss (N = 114) aged 3-5 years of age were assessed as to their ability to reconstruct or recognize spatial displays depicting Euclidean geometric features. The Ss responded either with the standard display present or in its absence, a memory condition. Items differed as to whether the objects located in the plane required attention to either one axis, the horizontal or vertical, or to both. In Study I Ss constructed their matches with an open-ended assessment device, while in Study II, they selected the match from a field of four distractors. Results from both studies were convergent despite differences in assessment technique and specifics of data analysis, and indicated an effect for age and condition, and that children do less well when dealing with double-axis displays in the memory condition. In addition, it appears that males were less attentive to display orientation cues than were females. Results are discussed in terms of Piagetian theoretical formulations about children's spatial development, their sensitivity to Euclidean spatial features, and the lack of synchrony between perceptual abilities and memory.

The largest number of women in history is employed outside the home including 55% of mothers with children less than 18 years of age. The attitudes of pediatricians toward employed mothers were assessed by a mail survey to the entire membership of the American Academy of Pediatrics. Usable responses were received from 5,758 pediatricians (31%). Adequacy of child care and economic necessity were ranked as the most important factors considered by responding pediatricians when advising a mother inquiring whether she should work outside the home. One third of the respondents stated the child can be any age when the mother becomes employed. The majority of respondents did not feel there was a difference between children of employed mothers and homemaker mothers. Special considerations for employed mothers were provided by half of the respondents, more frequently by female than male pediatricians. Most respondents are supportive of mothers working outside the home, but bias against employed mothers does exist. Pediatricians whose spouses do not work outside the home, those in older age groups, and male pediatricians tended to hold more traditional attitudes toward maternal employment.

Technical innovations may produce not only the changes they were intended to effect but also lead to consequences which are unexpected and sometimes destructive. There is an intimate relation between technological innovation and political power. Any great advances in reproductive technology are very likely to be controlled and commandeered by the state with all kinds of unforeseeable consequences.

We examined children's ability to anticipate the appearance of transformed multicomponents using visual stimuli with variations of a mental rotation task. We hypothesized that (a) performance would depend on the presence, location, and spatial relationship of specific stimulus features, and that (b) younger children would use a single component to make their predictions, whereas older children would be more likely to use multiple components. In Study 1, 40 first-, and fifth-grade subjects were presented with 32 rotation problems consisting of varied stimulus characteristics; subjects selected the correct option from a field where foils were indicative of the strategy used. Analyses of variance and log linear analyses revealed the hypothesized stimulus effect differentially associated with the children's ages. In Study 2, sixty 5-, 7-, and 9-year olds confronted 64 mental rotation problems with multicomponent stimuli and a construction task. Results and implications confirmed those of Study 1.

The development of a computer-based radiologic total lung capacity (TLC) measurement system designed to be used by non-physician personnel is detailed. Four operators tested the reliability and validity of the system by measuring inspiratory PA and lateral pediatric chest radiographs with a Graf spark pen interfaced to a DEC VAX 11/780 computer. First results suggest that the ultimate goal of developing an accurate and easy to use TLC measurement system for non-physician personnel is attainable.