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At least 271 records · Page 15Linked to original sources
PubMed1998

Don't let data become too much of a good thing in clinical path, outcomes tracking efforts.

Too much of a good thing? Are you collecting too much data? At University of Iowa Hospitals and Clinics, caregivers were tracking every variance to every item on every clinical pathway. It was just too much work, and the reports weren't even useful. A new variance tracking system includes targeting three to 10 key events for each pathway and has resulted in greater tracking compliance and data accuracy.

Benchmarking↗
PubMed1999

Medical student database development: a model for record management in a multi-departmental setting.

Student records flow through medical school offices at a rapid rate. Much of this data is often tracked on paper, spread across multiple departments. The Medical Student Informatics Group at the University of Utah School of Medicine identified offices and organizations documenting student information. We assessed departmental needs, identified records, and researched database software available within the private sector and academic community. Although a host of database applications exist, few publications discuss database models for storage and retrieval of student records. We developed and deployed an Internet based application to meet current requirements, and allow for future expandability. During a test period, users were polled regarding utility, security, stability, ease of use, data accuracy, and potential project expansion. Feedback demonstrated widespread approval, and considerable interest in additional feature development. This experience suggests that many medical schools would benefit from centralized database management of student records.

Consumer Behavior↗
PubMedDate not supplied

Heavy metal determination in aquatic species for food purposes.

New analytical procedures and sample mineralizations are proposed regarding the determination of arsenic, selenium, copper, lead, cadmium, zinc and mercury in matrices involved in food chain as mussel, clams and fishes. As regard As, Se, Cu, Pb, Cd and Zn determinations, H2SO4-HNO3 acidic mixture is used for the digestion of each matrix. In the case of Hg the sample digestion is performed using a concentrated suprapure H2SO4-K2Cr2O7 mixture and the results are compared with those from other conventional methods. Differential pulse cathodic (DPCSV) and anodic stripping voltammetry (DPASV) are employed for determining simultaneously selenium, arsenic and copper, lead, cadmium, zinc, respectively, while mercury determination is carried out by the cold vapour atomic absorption spectrometry (CV-AAS) with reduction with SnCl2. The voltammetric measurements were performed using a conventional three-electrode cell and the ammonia-ammonium chloride buffer (pH 9.3) as supporting electrolyte. For all the elements, in addition to the detection limits, precision and accuracy data are also reported: the former, expressed as relative standard deviation (Sr), and the latter, expressed as relative error (e), are in all cases between 3 to 6%.

Animals↗
PubMed2001

Noise-induced hearing loss among U.S. Air Force cryptolinguists.

BACKGROUND: Occupational noise-induced hearing loss remains epidemic in the U.S. Air Force (USAF) and aircrew members continue to be affected. This study examines noise-induced hearing loss (NIHL) observed among USAF cryptolinguists that is attributable to radio noise and attempts to determine whether the current USAF Hearing Conservation Program (HCP) adequately identifies NIHL. METHODS: Audiograms from 120 ground-based cryptolinguists were examined. Comparisons were made between 1998 audiograms and either the reference audiogram or the enlistment audiogram. To determine HCP effectiveness, results were compared with the USAF standard of 3% or fewer permanent threshold shifts (PTS) per year. RESULTS: Some 13.3% of the cryptolinguists experienced standard threshold shifts (STS) between their enlistment audiogram and their initial occupational (reference) audiogram; 9.2% experienced STS in 1998 as compared with their initial enlistment audiogram but only 6 of the 11 (54%) were detectable using the reference audiogram as the baseline. The frequency pattern of changes in hearing thresholds was characteristic for NIHL. CONCLUSIONS: The NIHL that occurs among cryptolinguists prior to performance of the reference audiogram, and the hearing threshold shifts that occur between the enlistment audiogram and the reference audiogram, may obscure future hearing loss in the population. The incidence of PTS appeared to exceed 3% when the enlistment audiogram was used. While this result was not significantly different from 3%, sample size limitations and data accuracy concerns warrant that this population be closely watched in the future.

Adult↗
PubMed2003

Predicting ready biodegradability of premanufacture notice chemicals.

Chemical substances other than pesticides, drugs, and food additives are regulated by the U.S. Environmental Protection Agency (U.S. EPA) under the Toxic Substances Control Act (TSCA), but the United States does not require that new substances be tested automatically for such critical properties as biodegradability. The resulting lack of submitted data has fostered the development of estimation methods, and the BioWIN models for predicting biodegradability from chemical structure have played a prominent role in premanufacture notice (PMN) review. Until now, validation efforts have used only the Japanese Ministry of International Trade and Industry (MITI) test data and have not included all models. To assess BioWIN performance with PMN substances, we assembled a database of PMNs for which ready biodegradation data had been submitted over the period 1995 through 2001. The 305 PMN structures are highly varied and pose major challenges to chemical property estimation. Despite the variability of ready biodegradation tests, the use of at least six different test methods, and widely varying quality of submitted data, accuracy of four of six BioWIN models (MITI linear, MITI nonlinear, survey ultimate, survey primary) was in the 80+% range for predicting ready biodegradability. Greater accuracy (>90%) can be achieved by using model estimates only when the four models agree (true for 3/4 of the PMNs). The BioWIN linear and nonlinear probability models did not perform as well even when classification criteria were optimized. The results suggest that the MITI and survey BioWIN models are suitable for use in screening-level applications.

Biodegradation, Environmental↗
PubMed2003

Developing a metadata data model for the National Health and Nutrition Examination Survey (NHANES).

The National Health and Nutrition Examination Survey (NHANES), developed by the Centers for Disease Control and Prevention (CDC), is a large and comprehensive health survey utilizing leading edge technologies to produce national estimates of health measures and the nutritional status of the U.S. population. Early NHANES metadata models grouped data by categories with little specificity and often not capturing the complexity of the survey. Subsequently, existing models at the Census Bureau, CDC, and the EPA were evaluated in addition to industry standards, such as DDI, Dublin Core, and ISO 1179. For the NHANES metadata model, the DDI standard and CDC Public Health Conceptual Model were chosen as the backbone for constructing the data model. The new model has led to increased data accuracy and several value-added products for producing codebooks, automatically checking questionnaire skip patterns, and producing questionnaire instrumentation.

Catalogs as Topic↗
PubMed2005

Ensuring the Quality of Aggregated General Practice Data: Lessons from the Primary Care Data Quality Programme (PCDQ).

BACKGROUND: There are large numbers of schemes that collect and aggregate data from primary care computer systems into large databases. These data are then used for market and academic research. How the data is aggregated, cleaned and processed is usually opaque. Making the method transparent allows researchers to compare methods, and users of the output to better understand the strengths and weaknesses of the data.Objectives To define the stages of the process of aggregating, processing and cleaning clinical data from multiple data sources. METHODS: Identify errors in design, collection, staging, integration and analysis. RESULTS: An eight step process defined: (1) Design (2) DATA: entry, (3) Extraction, (4) Migration, (5) Integration, (6) Cleaning, (7) Processing, and (8) Analysis. CONCLUSIONS: This eight step method provides a taxonomy to enable researchers to compare their methods of data process and aggregation.

Computer Systems↗
PubMedDate not supplied

Determination of total gossypol in cottonseed and cottonseed meals by derivative UV spectrophotometry.

A new method for the determination of total gossypol in cottonseed and cottonseed meals has been developed. The method involves oxalic acid hydrolysis of the bound gossypol in a methyl ethyl ketone-water azeotrope, partitioning the liberated gossypol into chloroform, and quantification by 2nd derivative UV spectrophotometry. The 2nd derivative transformation and measurement of the conventional analytical band around 300 nm permits direct quantification of all compounds containing naphthalene nuclei; chromogenic reaction is not required. The method was tested at concentration levels of total gossypol normally expected for cottonseed and cottonseed meal. Precision and accuracy data suggested an overall relative standard deviation of 4.0% and an overall recovery of 89.5%. Although results for cottonseed and solvent-extracted cottonseed meal analyses were comparable to those obtained by use of American Oil Chemists' Society methods, results were lower for screw-pressed meals. The lower results were attributed to the partial conversion of gossypol, during the cooking process of these meals, to compounds that differ in composition and structure from gossypol and which react with aniline to give false readings.

Aldehydes↗
PubMed1988

High-performance liquid chromatographic determination of trans-doxepin and desmethyldoxepin.

An improved high performance liquid chromatographic (HPLC) assay for the quantitative determination of trans-doxepin (I) and desmethyldoxepin (II) in body fluids is presented. This HPLC assay, employing a UV-detector and perazine (III) as an internal standard, provides a very sensitive and selective determination in the low ng/ml range. The lower limit of quantification was 0.426 ng/ml (I) and 0.50 ng/ml (II); respectively. The calibration curve was linear in the measured range of 0.426-34.08 ng/ml (I) and 0.50-40 ng/ml (II). In combination with the excellent precision and accuracy data (c.v. values typically lower than 5%) and a recovery exceeding 90% for both compounds, the method is well suited for quantitative determinations of plasma samples generated during clinical studies, eg. evaluating the pharmacokinetics and/or bioavailability/bioequivalence as well as evaluations of clinical response.

Antidepressive Agents, Tricyclic↗
PubMed1987

[Histologically controlled comparison of palpation and sonography in the diagnosis of cervical lymph node metastases].

During a period of 2 1/2 years palpation and high-resolution real-time sonography were carried out in 83 non-selected patients with head and neck carcinomas to diagnose metastatic involvement of cervical lymph nodes. The findings were compared with the results of the microscopic examination of the lymph nodes from the neck dissection specimen. Sonography is characterized by a high sensitivity in the detection of lymph node metastases. The relatively low specificity of this method proves that many enlarged but not metastatically involved lymph nodes are also displayed by ultrasound. Although there are no specific echomorphological criteria permitting a reliable identification of lymph node metastases, their sonographic visibility cannot be determined only by the size of the lymph node. Lymph node metastases less than 1.5 cm in diameter, in particular, can be detected more often by ultrasound than by palpation. Therefore, it can be presumed that pathological transformations besides the reactive hyperplasia occurring during metastatic involvement will also influence the echographic representation of lymph nodes. The accuracy data of other methods used for detecting lymph node metastases (computed tomography and lymphoscintigraphy) were compiled from the literature and compared with those of palpation in more than 5000 patients. Basing on our experiences with sonography in this field we tried to assess the chances and limitations of ultrasound in the pretherapeutic diagnosis of cervical lymph node metastases.

Carcinoma, Squamous Cell↗
PubMed1986

Intrauterine volume in pregnancy.

Intrauterine volume, a three-dimensional measure of growth, was evaluated in pregnancy. The ultrasonic method for measurement of volume was investigated for its accuracy and error potentials and then used to collect information on the growth of three volume components, - total intrauterine, intra-amniotic and placental volume, in the latter half of normal pregnancy. Against reference standards from the normal population, two other main groups, a non-selected and a pre-selected high-risk group, were studied, to test the hypothesis that a small intrauterine volume would predict the presence of a small-for-dates and possibly compromised baby. In previous times main interest in uterine volume had centered on its possible role in parturition. More recently ultrasound had been used to measure intrauterine volume in early pregnancy and a simple ultrasonic method of calculating total intrauterine volume had been used for diagnosing the small-for-dates fetus. The study showed that in a phantom model situation, a method based on serial parallel planimetric area measurements was significantly more accurate than a linear measurement method that assumed the uterine shape to be like a prolate ellipsoid. With the former method 93.3% of measurements were within +/- 5% of the true volume with a mean error of -0.43%. When the method was evaluated for its accuracy in women undergoing midtrimester termination or in women delivering near term, there was good correlation between ultrasonically and directly/indirectly measured intra-amniotic volume suggesting that the same level of accuracy could be expected in pregnancy as found in the phantom models. Intra- and interobserver variation was small. The PPA method was used for all measurements in pregnancy because of its superior accuracy. Data from 115 healthy women with no pregnancy complications were evaluated longitudinally to study normal growth and derive reference standards. Median and mean values for total intrauterine volume increased from around 1,000 ml at 20 weeks to 4,500 ml at 40 weeks. The standard deviation was large at any stage of pregnancy, also for intra-amniotic and placental volume. The rate of volume increase was near constant for total intrauterine and intra-amniotic volumes, except during the period 30-35 weeks, when a faster rise was observed. Placental volume growth decreased after 30 weeks. With growth of total volume following a largely linear trend, a tendency for ranking of volume levels was observed, but predictability of one measurement on the basis of earlier ones weakened with increasing separation of time points.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1979

A multicomponent, multipoint infrared ambient air monitor.

With the tremendous advances in electronics today, it is now possible to take existing analytical instruments and give then a "brain" so that many analytical procedures which were impossible or costly a few years ago can now be done with relative ease, at a fraction of the costs. This paper deals with a microcomputer-controlled air monitor which allows us to identify many different components at a multitude of different locations. System operation is explained as well as data accuracy as they relate to application in a plastics research pilot plant.

Air↗
PubMed1980

A radioimmunoassay for 6-keto-prostaglandin F1 alpha.

We describe a highly specific RIA for blood and urine 6-keto-PGF1 alpha, the principal metabolite of PGI2. The method requires extraction and column chromatography prior to assay and uses a tritium trace for assay monitoring. Dextran-coated charcoal is used to separate bound from free trace. Acceptable standard curve reproducibility over six assays had a mean correlation of 0.991 with a coefficient of variation of 6.61%. Good precision and accuracy data were generated with this assay, and normal human blood levels in 80 control subjects was less than 125 pg/ml. Significant elevations of blood 6-keto-PGF1 alpha were found in a high proportion of cancer patients with various solid tumor malignancies.

6-Ketoprostaglandin F1 alpha↗
PubMed1997

[Quality control in clinical testing--past and near future].

To provide clinical testing that is useful for medical treatment, it is essential to provide correct, reliable test results to doctors and patients, i.e. high-quality test data are always required for appropriate medical treatment. To fulfill this requirement, it is necessary to establish and smoothly manage a test quality control system designed to maintain a fixed level of data accuracy and precision. The history of quality control in clinical testing spans nearly 30 years and new developments and innovations are required in this field. In this memorial lecture, I will review the development of clinical laboratory testing and explore the potential for improved test result control in the near future.

Clinical Laboratory Techniques↗
PubMed1998

Neuroimaging for diagnosis of dementia.

Although many clinicians consider neuroimaging studies as optional for the differential diagnosis of dementia, clinical experience suggests that they can improve diagnostic accuracy. Data are limited, however, on sensitivity, specificity, and cost-effectiveness of various neuroimaging techniques. The author reviews advantages and disadvantages of neuroimaging techniques for the differential diagnosis of dementia and describes strategies used for early detection of Alzheimer's disease, including combining positron emission tomography scanning with genetic risk assessment. Such approaches could provide a means for in vivo therapeutic monitoring of brain function during experimental antidementia treatment trials.

Aged↗
PubMedDate not supplied

The accuracy of medication data in an outpatient electronic medical record.

OBJECTIVE: To measure the accuracy of medication records stored in the electronic medical record (EMR) of an outpatient geriatric center. The authors analyzed accuracy from the perspective of a clinician using the data and the perspective of a computer-based medical decision-support system (MDSS). DESIGN: Prospective cohort study. METHODS: The EMR at the geriatric center captures medication data both directly from clinicians and indirectly using encounter forms and data-entry clerks. During a scheduled office visit for medical care, the treating clinician determined whether the medication records for the patient were an accurate representation of the medications that the patient was actually taking. Using the available sources of information (the patient, the patient's vials, any caregivers, and the medical chart), the clinician determined whether the recorded data were correct, whether any data were missing, and the type and cause for each discrepancy found. RESULTS: At the geriatric center, 83% of medication records represented correctly the compound. dose, and schedule of a current medication; 91% represented correctly the compound. 0.37 current medications were missing per patient. The principal cause of errors was the patient (36.1% of errors), who misreported a medication at a previous visit or changed (stopped, started, or dose-adjusted) a medication between visits. The second most frequent cause of errors was failure to capture changes to medications made by outside clinicians, accounting for 25.9% of errors. Transcription errors were a relatively ucommon cause (8.2% of errors). When the accuracy of records from the center was analyzed from the perspective of a MDSS, 90% were correct for compound identity and 1.38 medications were missing or uncoded per patient. The cause of the additional errors of omission was a free-text "comments" field-which it is assumed would be unreadable by current MDSS applications-that was used by clinicians in 18% of records to record the identity of the medication. CONCLUSIONS: Medication records in an outpatient EMR may have significant levels of data error. Based on an analysis of correctable causes of error, the authors conclude that the most effective extension to the EMR studied would be to expand its scope to include all clinicians who can potentially change medications. Even with EMR extensions, however, ineradicable error due to patients and data entry will remain. Several implications of ineradicable error for MDSSs are discussed. The provision of a free-text "comments" field increased the accuracy of medication lists for clinician users at the expense of accuracy for a MDSS.

Aged↗
PubMed1996

Medical insurance claims as a source of data for research: accuracy of diagnostic coding.

Validation of diagnostic codes in a sample of Hawaii medical insurance claims in 1986 to 1987 revealed 96% accuracy in hospital claims, high enough to supply data for research purposes. In physician claims the accuracy was only 62%. Initiation of two feedback loops to physicians from the insurer in 1989 resulted in a marked improvement of diagnostic coding accuracy by 1992 to 1994.

Communicable Diseases↗
PubMed2005

Accuracy of intraoral data acquisition in comparison to the conventional impression.

The achievable accuracy is a decisive parameter for the comparison of direct intraoral digitization with the conventional impression. The objective of the study was therefore to compare the accuracy of the reproduction of a model situation by intraoral digitization vs. the conventional procedure consisting of impression taking, model production, and extraoral digitization. Proceeding from a die model with a prepared tooth 16, the reference data set of the teeth 15, 16 and 17 was produced with an established procedure by means ofextraoral digitization. For the simulated intraoral data acquisition of the master model (Cerec 3D camera, Sirona, Bensheim), the camera was fastened on a stand for the measurement and the teeth digitized seven times each in defined views (occlusal, and in each case inclined by 20 degrees, from the mesio-proximal, disto-proximal, vestibular and oral aspect). Matching was automated (comparative data sets B1-B5). A clinically perfect one-step putty-and-wash impression was taken from the starting model. The model produced under defined conditions was digitized extraorally five times (digi-SCAN, comparative data sets C1-C5). The data sets B1-B5 and C1-C5 were assigned to the reference data set by means of best-fit matching and the root of the mean quadratic deviation (RMS; root mean square) calculated. The deviations were visualized, and mean positive, negative and absolute deviations calculated. The mean RMS was 27.9 microm (B1-B5) or 18.8 microm (C1-C5). The mean deviations for the prepared tooth were 18 microm/-17 microm (B1-B5) and 9 microm /-9 microm (C1-C5). For tooth 15, the mean deviations were 22 microm/-19 microm (B1-B5) and 15 microm/-16 microm (C1-C5). The intraoral method showed good results with deviations from the CAD starting model of approx. 17 microm, related to the prepared tooth 16. On the whole, in this in-vitro study, extraoral digitization with impression taking and model production showed higher accuracy than intraoral digitization. Since the inaccuracies in the conventional impression under real clinical conditions may be higher than the values determined above, a comparison under clinical conditions should be performed subsequently.

Bicuspid↗