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PubMed2005

Evaluation of the National Congenital Anomaly System in England and Wales.

OBJECTIVE: To evaluate the National Congenital Anomaly System (NCAS). METHODS: The NCAS in England and Wales based at the Office for National Statistics and the various regional registers that exchange data with it were examined, based on guidelines for evaluating public health surveillance systems, published by the Centres for Disease Control (CDC). Data relating to congenital anomaly notifications received from 1991 to 2002 were analysed. MAIN OUTCOME MEASURES: The main outcome measures were based on CDC standards and included the level of usefulness of the system, simplicity, flexibility, data quality, acceptability, sensitivity, representativeness, timeliness, and stability of the system. RESULTS: The NCAS has two main tiers: the "passive" system of voluntary notifications and the anomaly registers, but many reporting sources within these. It receives about 7000 notifications a year. It is inflexible and has variable data quality. The voluntary nature of reporting affects the system's acceptability. The sensitivity as compared with two regional registers (Trent and Wales) is about 33%. The congenital anomaly registers reporting to the NCAS achieve high levels of coverage and completeness. From 2003, they cover 42% of all births and account for the major proportion of the notifications. CONCLUSIONS: The NCAS serves the important function of monitoring birth defects in England and Wales, but is not currently operating in a timely or effective way. It should be adapted to meet its main objectives more effectively. More regional anomaly registers should be instituted and existing registers supported through central funds.

Congenital Abnormalities↗
PubMed2005

Automated measurement of cell motility and proliferation.

BACKGROUND: Time-lapse microscopic imaging provides a powerful approach for following changes in cell phenotype over time. Visible responses of whole cells can yield insight into functional changes that underlie physiological processes in health and disease. For example, features of cell motility accompany molecular changes that are central to the immune response, to carcinogenesis and metastasis, to wound healing and tissue regeneration, and to the myriad developmental processes that generate an organism. Previously reported image processing methods for motility analysis required custom viewing devices and manual interactions that may introduce bias, that slow throughput, and that constrain the scope of experiments in terms of the number of treatment variables, time period of observation, replication and statistical options. Here we describe a fully automated system in which images are acquired 24/7 from 384 well plates and are automatically processed to yield high-content motility and morphological data. RESULTS: We have applied this technology to study the effects of different extracellular matrix compounds on human osteoblast-like cell lines to explore functional changes that may underlie processes involved in bone formation and maintenance. We show dose-response and kinetic data for induction of increased motility by laminin and collagen type I without significant effects on growth rate. Differential motility response was evident within 4 hours of plating cells; long-term responses differed depending upon cell type and surface coating. Average velocities were increased approximately 0.1 microm/min by ten-fold increases in laminin coating concentration in some cases. Comparison with manual tracking demonstrated the accuracy of the automated method and highlighted the comparative imprecision of human tracking for analysis of cell motility data. Quality statistics are reported that associate with stage noise, interference by non-cell objects, and uncertainty in the outlining and positioning of cells by automated image analysis. Exponential growth, as monitored by total cell area, did not linearly correlate with absolute cell number, but proved valuable for selection of reliable tracking data and for disclosing between-experiment variations in cell growth. CONCLUSION: These results demonstrate the applicability of a system that uses fully automated image acquisition and analysis to study cell motility and growth. Cellular motility response is determined in an unbiased and comparatively high throughput manner. Abundant ancillary data provide opportunities for uniform filtering according to criteria that select for biological relevance and for providing insight into features of system performance. Data quality measures have been developed that can serve as a basis for the design and quality control of experiments that are facilitated by automation and the 384 well plate format. This system is applicable to large-scale studies such as drug screening and research into effects of complex combinations of factors and matrices on cell phenotype.

Automation↗
PubMedDate not supplied

Additional day-to-day precision estimates based on regional chemistry quality control data.

State-of-the-art precision values are presented for the following serum constituents: aldolase (EC 4.1.2.13), alpha-hydroxybutyrate dehydrogenase (EC 1.1.1.30), cholinesterase (EC 3.1.1.8), cortisol, gamma glutamyl transferase (EC 2.3.2.2), haptoglobin, immunoglobulins, lactic acid, leucine aminopeptidase (EC 3.4.1.1), total lipids, osmolality, protein fractions, T3 uptake, thyroxine and vitamin B12. Precision estimates are based on values reported for four lyophilized serum pools analyzed by participants in the Pennsylvania Association of Clinical Pathologists regional quality control program for clinical chemistry, during 1976, 1977 and 1978. Use of the upper limit of the "most common range" of precision (that range including the 75 percent most precise laboratories) as a warning level for trouble-shooting is advocated.

Blood Chemical Analysis↗
PubMed2002

Implementation of an electronic logbook for intensive care units.

Logbooks of patients treated in acute care units are commonly maintained; the data may be used to justify resource use, analyze patient outcomes, and encourage clinical research. We report herein the conversion of a paper-based logbook to an electronic logbook in three hospital intensive care units. The major difference between the paper logbook and electronic logbook data was the addition of clinician-entered data to the electronic logbook. Despite extensive computerization of patient information extant in the participating units, there was considerable reluctance to replace the paper-based logbook. The project's success can be attributed to the use of feedback from the clinical users in the development and implementation process to create accessible, high quality data. These data provide clinicians with the capability to monitor trends in a variety of patient groups. Advantages of the electronic logbook include more efficient data access, higher data quality and increased ability to conduct quality improvement and clinical research activities.

Attitude to Computers↗
PubMed1997

Developments in the application of impact assessment methodologies for pollution prevention.

Pollution prevention requires the assessment of various multimedia environmental impacts to ensure that the alternative selected most closely represents the environmental goals and priorities of the facility. While some facility's environmental policies are easy to assess (e.g., reduce TRI emissions), others require a more sophisticated assessment methodology (e.g., select the most environmentally-friendly manufacturing process). Chemical environmental impact assessment for pollution prevention can be very effective, but can only provide a scientifically defensible decision point if the methodologies, analytical tools, and data quality are consistent with the environmental goals and priorities expressed. In many assessments completed in the past, the assessment methodologies have been overly simplistic when compared to the environmental goals projected. More sophisticated chemical impact assessment methodologies have not been used in the past for a variety of reasons, including: poor study design, poor data quality, inadequate funding, inadequate computer systems and databases, and practitioner's lack of understanding. This paper will describe a broad range of assessment methodologies, the steps involved in various evaluations, various resources available to conduct pollution prevention impact assessments, and on-going methodology development.

Ecology↗
PubMed2006

Ion-trap tandem mass spectrometry-based analytical methodology for the determination of polychlorinated biphenyls in fish and shellfish. Performance comparison against electron-capture detection and high-resolution mass spectrometry detection.

Optimization of the Varian Saturn 2200 ion-trap tandem mass spectrometry (IT-MS/MS) system and comparison of its data quality with two other detection methods [electron-capture detection (ECD) and high-resolution mass spectrometry (HRMS)] was pursued by measuring polychlorinated biphenyls (PCBs) levels in fish and shellfish samples. IT-MS/MS methodology provided limits of detection (LOD) comparable to those obtained by ECD but superior specificity for the detection of a selected number of 39 PCB native congeners and 9 (13)C-labelled PCB standards. The method detection limits (MDLs) established for IT-MS/MS ranged between 1.0 and 5.0 pg/g on a wet weight basis while those obtained by ECD and HRMS were 1.0-4.0 pg/g and 0.1-2.0 pg/g, respectively. Overall, the results obtained in the study demonstrate that gas chromatography (GC) combined with IT-MS/MS provide higher data quality than those achievable by GC-ECD. For this particular set of target analytes the specificity achievable with IT-MS/MS was comparable to that obtained by HRMS and both techniques provided comparable data in terms of accuracy and precision.

Animals↗
PubMed1981

Stability of sodium and potassium in lyophilized quality control serum. A study of data from the Quality Assurance Service Program of the College of American Pathologists.

The long-term prereconstitution stability of sodium and potassium in large pools of lyophilized quality control serum used in Regional Quality Control Programs, conducted between 1977 and 1980 is reviewed. In approximately one third of 27 pools studied, minimal but significant increases in sodium concentration were detected, these increases averaged less than 0.50 per year and confirmed our previously reported results from pools analyzed between 1973 and 1976. Results relating to potassium stability have been inconsistent. The previously reported tendency for potassium to increase in some pools was again suggested by data obtained from laboratories using automated flame-emission photometry procedures. This was not confirmed, however, by the data reflecting manual/semi-automated flame-emission photometry procedures or automated electrode methods. It is postulated, that the source of sodium causing the increases in concentration is the glass containers in which control materials are stored between the time of manufacture and reconstitution. Regression analysis against time of monthly interlaboratory means, from participants in Regional Quality Control Programs, is a useful tool for evaluating postmanufacture stability of analytes in pools used for daily internal quality control procedures.

Blood Preservation↗
PubMed2005

Models for estimating parameters of neutral detergent fiber digestion by ruminal microorganisms.

Model assumptions included number of concurrently degrading entities (or pools) and expected distributions of undegraded NDF. Degradation processes modeled included a single pool with ruminal age-constant rates (exponential distribution), a single pool with a ruminal age-dependent rate, two pools with age-constant rates, two pools with age-dependent and age-constant rates, and a continuum of pools with a gamma distribution of age-constant rates. Various sizes of ingestively masticated fragments of bermudagrass hay or corn silage were obtained via wet sieving of esophageal masticate and incubated in vitro with ruminal fluid for 0 h, every 6 h up to 48 h, and every 12 h up to 168 h. Models assuming a single pool of age-constant or age-dependent rates had larger mean residual mean squares (P < 0.05) than did the gamma mixture model or the two-pool models. Degradation rates estimated by the gamma mixture model indicated distribution of rates ranging from near exponential, age-constant distribution to a near normal bell-shaped distribution of age-constant rates for different datasets. Superior fit by the two-pool models in most datasets (83%) indicated that having two resolvable entities of potentially degradable NDF with different degradation rates was causal of a biphasic distribution of lifetimes. Increasing order of age-dependency modeled in the two-pool model improved fit and precision of estimation (standard error of estimate) for the limit parameters of time delay and indigestible NDF. Both the gamma mixture continuum of age-constant rate model and the two-pool, age-dependent models with a discrete time delay provided similar fit to data and flexibility for fitting data with lifetime distributions ranging from simple exponential to sigmodial. The two-pool, age-dependent and gamma-distributed, age-constant models were better in fitting the dominant biphasic lifetime distributions that occurred when the two pools of degrading entities were of similar size and in estimating the discrete time delay when strategic, quality data were available. Having fewer parameters (four), the gamma-distributed, age-constant model was superior when data quality was limited.

Animal Nutritional Physiological Phenomena↗
PubMed2001

[Geriatric care in Germany--results of an empirical study].

BACKGROUND: In Germany, the situation of geriatric medicine has improved significantly over the past few years. Until now, though, there was little information available on the structure of the clinical geriatric departments. Since this information is vital to assess whether these departments can provide high-quality services, the German Federal Association of Clinical Geriatric Departments conducted a survey among its members. The goal was to gain deeper insight into the structure of the geriatric acute hospitals and rehabilitation units. METHODS: In 1999, member institutions were mailed a standardized questionnaire and all institutions (100%) returned the questionnaire to the association's central office. To increase data quality, data were screened and reports were generated for each institution. These reports were returned to the institutions which were asked to verify them. RESULTS: This article shows that in 1998 acute geriatric hospitals (n = 89), rehabilitation units (n = 52), acute day clinics (n = 45) and rehabilitation day clinics (n = 26) had--on average--60/60/15.3/14 beds/places and 828.15/677.3/164.2/125.9 patients. Occupancy rates averaged out at 88.7%/84.3%/86.4%/63.7% and daily hospital rates at DM 401.4/322.4/293.8/243.2. Basically, all geriatric institutions included in this survey had a multi-professional geriatric team. Patient-to-staff ratios for psychologists, social workers, ergo-, physio- and speech therapists were better in day clinics than in in-patient clinics and better in rehabilitation units than in acute hospitals. Geriatric institutions mainly focused on the treatment of neurological deficits. Most patients were admitted from other hospitals and discharged to their private residence. CONCLUSIONS: The results of this survey indicate that especially the acute hospitals are often not sufficiently staffed. Moreover, further efforts are necessary to clarify the indications for and modalities of geriatric day clinic treatment and rehabilitation. The data also show that a categorical distinction between geriatric acute hospitals and rehabilitation units is not possible. However, further data collection and more detailed analyses are needed.

Aged↗
PubMed2003

[First evaluation of the surveillance systems of notifiable diseases under the infectious disease control law in Germany].

INTRODUCTION: The implementation of the infectious disease control law (IfSG) in 1.1.2001 standardised the German surveillance system for notifiable diseases. For management and transmission of reports health departments use either the software programme Surv Net@RKI, which was developed by the Robert Koch-Institut (RKI), or one of five commercially offered disease-reporting software. After more than one year of its existence, we investigated the success of the implementation of the new surveillance system with the aim to identify possibilities for further improvement. METHODS: Based on 2001 data available to the RKI, we evaluated the criteria simplicity (standardisation of legal regulation and of software systems), acceptability (number of reporting regional counties), time (period from data entry at the health department to entry at the RKI) and data quality (information on immunisation status among reports of hepatitis A cases). RESULTS: For electronic processing 5 versions of Surv Net@RKI and 47 versions of the 5 commercial products are used. Additional rules of individual states expand the legal obligation for notification of the IfSG, by adding new diseases, different definitions or different reporting channels. Within the first quarter after implementation of the IfSG, 393 (90 %) of the 425 counties transmitted data weekly. The median transmission time from data entry at the health department and entry at the RKI was 5 to 7 days after the fourth reporting week. The proportion of hepatitis A case reports with information on immunisation status was 58 % (1323 of 2277); among the 1052 reports by health departments using Surv Net@RKI the proportion was 82 % (n = 858); among the 1225 reports from health departments using other programmes the proportion was 38 %. CONCLUSION: Implementation of the new surveillance system is successful. Electronic data systems should be standardised to improve data quality and simplicity. The deadlines for transmission should be shortened to allow earlier detection and control of multi-state outbreaks. State-specific rules on notifiable diseases should be standardised to avoid conflicting or redundant reporting channels.

Communicable Disease Control↗
PubMed2000

Structure determination of tubular crystals of membrane proteins. III. Solvent flattening.

Solvent flattening is considered to be a principal means for improving the data quality in X-ray crystallography. It could be equally effective for tubular crystals of membrane proteins imaged by electron microscopy because of the large empty space inside the tubes. However, tubular crystals are difficult objects for solvent flattening due to lack of electron diffraction amplitudes. Therefore, solvent flattening was used to align images more accurately and to improve the completeness of the data by reducing contributions of noise in the solvent (+ lipid) region. The methods developed were tested with the tubular crystals of Ca2+-ATPase embedded in amorphous ice. The improvement of the data quality was remarkable when solvent flattening was applied to many individual images before averaging. In this way, noises contaminated in the protein region by contrast transfer function were removed effectively. Solvent flattening was far more powerful than simple averaging described in Part II of this series (K. Yonekura, C. Toyoshima, Ultramicroscopy 84 (2000) 15).

Calcium-Transporting ATPases↗
PubMed2005

MetaCyc and AraCyc. Metabolic pathway databases for plant research.

MetaCyc (http://metacyc.org) contains experimentally determined biochemical pathways to be used as a reference database for metabolism. In conjunction with the Pathway Tools software, MetaCyc can be used to computationally predict the metabolic pathway complement of an annotated genome. To increase the breadth of pathways and enzymes, more than 60 plant-specific pathways have been added or updated in MetaCyc recently. In contrast to MetaCyc, which contains metabolic data for a wide range of organisms, AraCyc is a species-specific database containing only enzymes and pathways found in the model plant Arabidopsis (Arabidopsis thaliana). AraCyc (http://arabidopsis.org/tools/aracyc/) was the first computationally predicted plant metabolism database derived from MetaCyc. Since its initial computational build, AraCyc has been under continued curation to enhance data quality and to increase breadth of pathway coverage. Twenty-eight pathways have been manually curated from the literature recently. Pathway predictions in AraCyc have also been recently updated with the latest functional annotations of Arabidopsis genes that use controlled vocabulary and literature evidence. AraCyc currently features 1,418 unique genes mapped onto 204 pathways with 1,156 literature citations. The Omics Viewer, a user data visualization and analysis tool, allows a list of genes, enzymes, or metabolites with experimental values to be painted on a diagram of the full pathway map of AraCyc. Other recent enhancements to both MetaCyc and AraCyc include implementation of an evidence ontology, which has been used to provide information on data quality, expansion of the secondary metabolism node of the pathway ontology to accommodate curation of secondary metabolic pathways, and enhancement of the cellular component ontology for storing and displaying enzyme and pathway locations within subcellular compartments.

4-Hydroxyphenylpyruvate Dioxygenase↗
PubMedDate not supplied

Temporal changes in the vertical distribution of flow and chloride in deep wells.

The combination of flowmeter and depth-dependent water-quality data was used to evaluate the quantity and source of high-chloride water yielded from different depths to eight production wells in the Pleasant Valley area of southern California. The wells were screened from 117 to 437 m below land surface, and in most cases, flow from the aquifer into the wells was not uniformly distributed throughout the well screen. Wells having as little as 6 m of screen in the overlying upper aquifer system yielded as much as 50% of their water from the upper system during drought periods, while the deeper parts of the well screens yielded 15% or less of the total yield of the wells. Mixing of water within wells during pumping degraded higher-quality water with poorer-quality water from deeper depths, and in some cases with poorer-quality water from the overlying upper aquifer system. Changes in the mixture of water within a well, resulting from changes in the distribution of flow into the well, changed the quality of water from the surface discharge of wells over time. The combination of flowmeter and depth-dependent water quality data yielded information about sources of high-chloride water to wells that was not available on the basis of samples collected from nearby observation wells. Changing well design to eliminate small quantities of poor-quality water from deeper parts of the well may improve the quality of water from some wells without greatly reducing well yield.

Chlorides↗
PubMedDate not supplied

[Study of access to health care and drugs in Cameroon: 1. Methods and validation].

During the 1980s, an economic depression and the concomitant decrease in the national health budget modified the population's health behavior. Improvement of the economy since the late 1990s makes it possible to renew the national health policy. To prepare the highly indebted and poor countries' program (HIPC), the Minister of Health and its partners commissioned a survey to measure the population's real access to health care and the factors that determine this accessibility and to propose concrete corrective actions. To fulfill these objectives, the steering committee decided to analyze health care demand, through a national population survey, and supply capacity, through a national survey of pharmacies and other drug dispensers. A survey of persons using medications will also be conducted (Fig.1). Focusing on this component of health care is justified by these findings: 95% of persons feeling ill buy drugs, whereas only 31% consult a physician or other healthcare provider, and half of the average household's health expenditures are for drugs. Financial, geographic, social and quality indicators were defined to measure accessibility and its determining factors (Table 1). The smallest administrative unit, the health area (HA), was chosen as the sampling unit, to enable us to survey together healthcare demand, supply and consumption according to different concentrations of supply and demand . It behaves as a cluster of sampling units of different populations: drug retailers of all sectors, drug users, households, and ill persons within the households. The HA samples include Yaounde and Douala, with urban and rural sub-samples, for which sampling ratios increase with the diversity of supply and demand, according to several pre-defined factors. The study includes 400 HAs, covering more than one third of the population (Table 2). Within these HAs, 900 pharmacies and other formal drug retailers, 709 street vendors, 4,505 households, 2,532 ill persons in these households, 4,121 pharmacy customers and 850 customers of street vendors were surveyed, i.e., more than 13,600 questionnaires. Assessment of data quality shows that the sample is representative of the national population for its socioeconomic characteristics. Its geographic distribution, even after correction, nonetheless favors urban areas, where both supply and demand are high. Generalizing the 3 sub-samples to the national level thus requires caution, especially for the geographic distribution. Other limitations and possible biases are described and evaluated. However, the retrospective demographic and statistic evaluation shows that the samples are representative of their population and that the data quality can be considered good. This article describes the background of this study and justifies its methodological choices. Future publications will analyze the data collected.

Adolescent↗
PubMed2000

The optical conditioning of Cerec preparations with scan spray.

Coating the surfaces with an anti-reflection substance before taking the optical impression is indispensable for exposures with the Cerec camera. Up to now, this has been done mainly by powdering with titanium dioxide. Errors which have a negative influence on the result can, of course, arise during the coating process. Although powdering is a proven method which has led to outstanding results in many thousands of restorations, it represents a weak spot in the clinical procedure. In the present study, the handling and data quality of an innovative spray for applying an anti-reflection coat to restoration surfaces were examined. The values obtained were chiefly displayed in the Section window of the Cerec 3 software. Despite a few small problems, handling can be considered good and safe. The primary advantage consists in the display of the preparation boundaries, since the coated surface can be dried with an air stream. With regard to detail reproduction, data quality, and coat thickness, the quality of the optical impression has reached a new level. The present study shows that considerable errors can arise in the restoration from powdering, due partly to material buildup. The Scan Spray tested can be recommended for clinical use.

Aerosols↗
PubMed2001

Computer-based collection of mammographic exposure data for quality assurance and dosimetry.

PURPOSE: There is potentially more to quality assurance in mammography than the MQSA mandated tests. In this paper we describe a method of capturing individual mammogram technical parameters and the creation of new measures. These include the numbers of images required for each screening examination by technologist, median compression by technologist, and the radiation dose of the examination to the general population of patients. METHOD/MATERIALS: With this method we describe a semiautomated method of the collection of technical data from mammography exposures. The data that are automatically created by the mammography unit are saved on a computer for later analysis. The method was used on 2738 consecutive screening mammography examinations and 13 621 exposures from one machine. Data were obtained from November 1998 through December 1999. RESULTS: Using standard methods, the mean glandular dose (MGD) per exposure was 2.62 mGy (SD 1.2). The mean dose per bilateral screening examination was 6.53 mGy (SD 3.07), the median dose was 6.11 mGy, and the dose range was 1.13-34.23 mGy. Rhodium filtration was used for 18% of the exposures. The average and median breast thickness was 4.9 cm. The ACR phantom MGD for this machine was 2.44 mGy at 25 kVp, and 1.97 mGy at 26 kVp. The mean number of exposures for a bilateral mammogram was 4.9, and varied by a technologist from 4.7 to 5.2. The mean compression pressure varied by technologist from 13 to 30 lbs (58-134 N). CONCLUSIONS: The mean dose per mammogram is slightly greater than the ACR phantom dose at 25 kVp. Almost five exposures were necessary for a standard bilateral examination, and this varied by technologist. The compression used also varied by technologist. The semiautomated collection of technical data can aid in maintaining an effective mammography QA program.

Automation↗
PubMedDate not supplied

[Traffic accidents in a city in Southern Brazil: an evaluation of coverage and quality of data].

The aim of this study was to analyze police coverage and the validity of data on emergency and hospitalization records as well as on death certificates for traffic casualties in Londrina, Paraná State, Brazil. Victims (3,643) of road accidents during the first semester of 1996 were investigated and followed up after 180 days to confirm whether death was due to the accident. Police data recorded only 32.5% of the casualties, the coverage being higher for car occupants (71.6%) and lower for cyclists (8.1%) and pedestrians (24.8%). Agreement was low between original information and that derived from investigation of death certificates (Kappa coefficient 0.10; 95% CI: 0.02-0.17), fair for hospitalization records (Kappa coefficient 0.33; 95% CI: 0.27-0.40), and substantial for emergency records (Kappa coefficient 0.63; 95% CI: 0.61-0.65). Results suggest that police data underestimate the number of traffic casualties and that it is necessary to improve the validity of medical records.

Accidents, Traffic↗