Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Data Accuracy”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,009 records · Page 56Linked to original sources
PubMed2003

The diagnostic accuracy of computed tomography angiography for traumatic or atherosclerotic lesions of the carotid and vertebral arteries: a systematic review.

INTRODUCTION: Helical computed tomography angiography (CTA) has become an established technique for evaluating atherosclerosis of the cerebrovascular arteries. However, the role of CTA in penetrating and blunt trauma to the carotid and vertebral arteries is not well defined. We conducted a systematic literature review to determine the diagnostic accuracy of CTA for atherosclerotic, penetrating and blunt lesions in the carotid and vertebral arteries. METHODS: We searched MEDLINE and EMBASE databases to identify studies evaluating the diagnostic accuracy of CTA of the carotid and vertebral arteries published between January 1, 1992 and December 31, 2002. Two reviewers independently assessed abstracts and full text to determine study eligibility. Information on methodological quality, imaging technique and diagnostic accuracy was abstracted from all eligible studies by three independent reviewers. We pooled sensitivity and specificity data from diagnostic accuracy studies of high methodological quality. RESULTS: Forty-three articles met the inclusion criteria and were included in the review. Thirty studies examined atherosclerotic disease, two blunt trauma, two penetrating trauma and nine examined patients with other pathology. Pooled data from 15 higher quality studies demonstrated that CTA had a sensitivity of 95% (91-97% CI) for detecting severe (>70%) atherosclerotic stenosis of the carotid artery. The specificity of CTA for severe stenosis was also high 98% (96-99% CI). CTA remained a sensitive technique (95%; 93-97% CI) when the criterion for a positive result is relaxed to moderate or greater (>30%) stenosis. Two studies raised concerns about the use of CTA in the blunt trauma setting, suggesting that CTA may not be sensitive for detecting small intimal injuries, although both of these studies used older technologies for either obtaining or viewing images. Conversely, two penetrating trauma studies concluded that the sensitivity of CTA was high. CONCLUSIONS: Our findings demonstrate that CTA is both a sensitive and specific imaging technique for identifying severe atherosclerotic stenosis and occlusion of the carotid arteries. However, there is currently not enough high quality evidence to accurately estimate the sensitivity and specificity of CTA in the setting of blunt or penetrating trauma.

Angiography↗
PubMedDate not supplied

Limitations of secondary data sets for road traffic injury epidemiology: a study from Karachi, Pakistan.

OBJECTIVES: To evaluate the completeness of descriptive information and accuracy of ambulance data when compared with two other secondary sources of data, namely, medical examiners' reports and medical records, in the city of Karachi, Pakistan. METHODS: A retrospective chart review was carried out of all road traffic injury (RTI) victims transported by an ambulance service in Karachi from January 1 to December 31, 2003. Information on the name, age, and gender of the victim, date, time, and place of injury, and type of injury and its outcome was obtained, and then compared with medical examiners' data and inpatient medical records. The variables missing in the ambulance service database were identified. RESULTS: The ambulance service transported 1,245 RTI patients during 2003, 81% of whom were taken to one of three trauma centers. Twenty percent died before reaching hospital. There were missing variables in 340 (27%) cases, the majority of which were the unique identifiers such as name and age (67%). Data on other variables were reported in 95% or more cases. None of the medical examiners' reports or inpatient medical records contained a description of event of injury. The agreement rate for the variables available in the three data sets ranged from 61% to 100%. CONCLUSION: Secondary data on injuries, such as ambulance reports, medical examiners' reports, and medical records, have significant limitations. In Karachi, except with regard to unique identifiers, ambulance data seem to provide information just as accurate as that in medical examiners' and inpatient medical records.

Accidents, Traffic↗
PubMed1997

Comparing claims data and self-reported data with the medical record for Pap smear rates.

The objective of this study was to assess and compare the relative accuracy of claims data and patient self-reported information with medical records for Pap smear rates. A retrospective analysis of information obtained from administrative claims files, patient medical records, and a telephone survey was performed of 400 women age 19 through 75 years who were randomly selected for participation in the study. The data were obtained from a large multispecialty group practice in Minneapolis, Minnesota for the study years 1991 through 1993. Information from administrative claims regarding Pap smear status corresponded highly with information in the medical record (sensitivity 95% or higher; specificity 95% or higher; kappa 0.896 or better). Self-reported information from the telephone survey did not correspond well with medical record information nor with results in administrative claims.

Adult↗
PubMed1997

Bow, range, and sequential effects in absolute identification: a response-time analysis.

Accuracy and response time (RT) measures were obtained in the absolute identification of line length. Different groups of subjects performed the task under different experimental conditions where range and relative spacing were the main independent variables. For comparison purposes, another group of subjects performed a digit-identification task. Results were analyzed for bow, range, and sequential effects using both accuracy and RT data. A preliminary analysis of RT distributions was also performed. Several phenomena previously documented using accuracy are reproduced, while new observations are reported for RT. The results show a dissociation between RT and accuracy in that the experimental manipulations sometimes affected accuracy but not necessarily RT.

Adult↗
PubMed2004

The burden and cost of hospitalised varicella and zoster in Australian children.

BACKGROUND: Economic analyses of varicella-zoster virus (VZV) immunisation are sensitive to the costs of hospitalised cases, so there is a need to validate VZV hospitalisation data. AIMS: To assess the accuracy of hospital VZV coding data and to apply these parameters to a population-based sample to estimate incidence and costs. METHODS: A 3-year retrospective chart review from one hospital to document clinical features and validate coding data. A separate 9-year analysis of discharge data from two hospitals draining a defined region of suburban Melbourne, with adjustment for miscoding and estimates of direct hospital costs. RESULTS: After correction for miscoding, 224 patients were admitted to one hospital over 3 years, 79% with varicella and 21% with zoster. Miscoding resulted in a 15% underestimate of zoster cases and a 4% overestimate of varicella cases. Thirty-six percent of varicella admissions compared to 80% of zoster admissions were immunocompromised and/or had chronic disease. Compared to otherwise-healthy patients, immunocompromised patients were admitted earlier in their illness and had lower complication rates. Forty-two percent of immunocompromised/chronic disease patients with varicella had a known exposure, usually from a family member. The incidence of hospitalised varicella and zoster in under 15-year olds was 15.7 and 1.8 per 100,000 per year, respectively. This suggests that there are 615 varicella hospitalisations and 72 zoster hospitalisations in this age group each year in Australia, at a total direct cost of over 2.2 million AU dollars. CONCLUSION: These results highlight the considerable burden of hospitalised zoster and the importance of immunising non-immune contacts of immunocompromised individuals. They also support previous estimates of the incidence of hospitalised varicella in Australian children and adolescents, although direct medical costs may be higher than those previously estimated.

Adolescent↗
PubMed2006

Molecular dynamics study of the thermodynamic properties of calcium apatites. 2. Monoclinic phases.

Structural and thermodynamic properties of crystalline monoclinic calcium apatites, Ca10(PO4)6(X)2 (X=OH, Cl), were investigated for the first time using a molecular dynamics (MD) technique under a wide range of temperature and pressure conditions. The accuracy of the model at room temperature and atmospheric pressure was checked against crystal structural data, yielding maximum deviations of ca. 2%. The standard molar lattice enthalpy (DeltalatHo298) of the apatites was also calculated and compared with previously published experimental and MD results for the hexagonal polymorphs. High-temperature simulation runs were used to estimate the isobaric thermal expansivity coefficient and study the behavior of the crystal structure under heating. The heat capacity at constant pressure, Cp, in the range 298-1298 K, was estimated from the plot of the molar enthalpy of the crystal as a function of temperature, Hm=(Hm,298-298Cp,m)+Cp,mT, yielding Cp,m=635+/-7 J.mol-1.K-1 and Cp,m=608+/-14 J.mol-1.K-1 for hydroxy- and chlorapatite, respectively. High-pressure MD experiments, in the 0.5-75 kbar range, were performed to estimate the isothermal compressibility. The Parsafar-Mason equation of state was successfully used to fit the high-pressure p-Vm data, with an accuracy better than 0.03%.

Journal Article↗
PubMed1995

The National Cancer Institute audit of the National Surgical Adjuvant Breast and Bowel Project Protocol B-06.

BACKGROUND: The National Surgical Adjuvant Breast and Bowel Project (NSABP) Protocol B-06, a clinical trial sponsored by the National Cancer Institute (NCI), has provided evidence of the value of lumpectomy and breast irradiation for treating women with breast cancer in an early stage. Publicity generated by the discovery that the study included fraudulent data on patients enrolled by St. Luc Hospital in Montreal aroused concern about the overall accuracy of the data and conclusions. To address this concern, the NCI conducted an audit of other participating institutions. METHODS: In 1994, data on 1554 of the 1809 randomized patients (85.9 percent) enrolled by centers other than St. Luc Hospital were audited at 37 clinical sites in North America. The audit included data on eligibility, survival, disease-free survival, the length of time to a recurrence of cancer in the ipsilateral breast, and documentation of signed informed consent. RESULTS: End points were assessed for all 1554 patients, and eligibility was assessed for 1507 patients; 47 patients were excluded because their forms were not complete or not returned. A total of 1429 patients had their eligibility status verified. Of a total of 7770 data points examined with respect to the number of positive nodes at base line, treatment characteristics, first events (excluding death), recurrence of cancer in the ipsilateral breast, and survival, 7577 (97.5 percent) were verified, 123 (1.6 percent) could not be verified, and 70 (0.9 percent) were discrepant with the NSABP file. Of the 1554 patients, 1340 (86.2 percent) had all audited items (including eligibility) verified, 69 (4.4 percent) had at least one discrepant item, and 113 (7.3 percent) had at least one unverified item (as a result of missing or incomplete data); 32 (2.1 percent) were not assessed for eligibility but had no other discrepant or unverifiable items. Written informed consent was documented for 1098 patients before surgery and 210 after surgery; no date appeared on the signed form for 137. The informed-consent status was not verified for 71 patients and could not be determined for 38. The rates of verification of end-point data and documentation of written informed consent were similar among the total-mastectomy group, the lumpectomy group, and the group treated by lumpectomy and breast irradiation. CONCLUSIONS: The audit confirms the adequacy of the data on which the reanalysis of Protocol B-06 and the results after 12 years of follow-up are based.

Breast Neoplasms↗
PubMed1989

Rapprochement and other crises. The specific and nonspecific in analytic reconstruction.

The historical development of preoedipality in evolving psychoanalytic theory is traced. Particular reference is paid to the elaboration by Mahler of the separation-individuation phase and the specific rapprochement conflict and crisis within it. In addition to the valuable contributions these discoveries have brought about, the tendency is noted for every new locus of interest to be obscured by excessive claims, and distorted by overuse and reductionism to explain complex and multidetermined behavior. This leads to the question of the specific and nonspecific in analytic reconstruction. Psychoanalysis invites a search for the specific superimposed upon the general. What I believe is nonspecific is the experience of the traumatic state, variable in degree, and the anxiety always adherent to it. The cognitive and historical data which initiated and maintain these affective states need to be arrived at with clinical accuracy and sustaining data, transference and historical. With discipline and restraint, and effective clinical bridges for interpretation, reapprochement and other distant preoedipal determinants can be pointed to in analytic reconstruction with confidence and profit to the analysis. Clinical examples are cited of valid and therapeutically effective reconstruction of early infantile traumas, including reapprochement, as well as instances in which significant etiologic determinants from contiguous phases are fused and continuous. Reapprochement plays an important role, but the temptation to isolate it is to be tempered with an openness to all levels and an awareness of the continuing developmental line. Such a wide etiologic spectrum is in keeping with the total range of observations and formulations made by Mahler, from the psychological birth of the infant, through separation-individuation, to phenomena and stages long after the attainment of object constancy.

Adolescent↗
PubMedDate not supplied

The accuracy of medical records and police reports in determining motor vehicle crash characteristics.

OBJECTIVE: To determine the accuracy of police, emergency department, and ambulance records in describing motor vehicle crash (MVC) characteristics when compared with a crash investigation report (CIR). METHODS: This study was a retrospective record review. Sixty-three motor vehicle crash (MVC) patients transported to a university hospital emergency department via ambulance and also reported in a crash investigation record (CIR) during the period January 1993 to December 1995 comprised the study population. The crash characteristics analyzed were occupant position (OP), restraint use (RU), air bag deployment (AD), type of impact (TI), ejection (EJ), and external cause-of-injury code (EC). The accuracies of the police report (PR), the emergency department record (EDR), and the ambulance report (AR) for each patient were compared with the CIR by computing percent agreement, with 95% confidence intervals (95% CIs) for each variable and for each data source. RESULTS: Overall average agreement was 92.9% for PR, 89.7% for EDR, and 80.7% for AR. The overall average agreement for each variable was 98.9% for EJ, 92.1% for AD, 91.5% for OP, 90.5% for EC, 77.2% for RU, and 76.2% for TI. For all but one variable (RU), 95% CIs overlapped between data sources. CONCLUSIONS: The accuracy of data sources used to determine crash characteristics varies. Using a CIR as the standard, the PR was the most accurate. Inaccuracies occurred most frequently for RU and TI. Researchers and clinicians need to be aware of these inaccuracies.

Accidents, Traffic↗
PubMed2002

An efficient and accurate distance based algorithm to reconstruct tandem duplication trees.

UNLABELLED: The problem of reconstructing the duplication tree of a set of tandemly repeated sequences which are supposed to have arisen through unequal recombination, was first introduced by Fitch (1977, Genetics, 86, 93-104), and has recently received a lot of attention. In this paper, we describe DTSCORE, a fast distance based algorithm to reconstruct tandem duplication trees, which is statistically consistent. As a cousin of the ADDTREE algorithm (Sattath and Tversky, 1977, Psychometrika, 42, 319-345), the raw DTSCORE has a time complexity in O(n(5)), where n is the number of observed repeated sequences. Through a series of algorithmic refinements, we improve its complexity to O(n(4)) in the worst case, but stress that the refined DTSCORE algorithm should perform faster with real data. We assess the topological accuracy of DTSCORE using simulated data sets, and compare it to existing reconstruction methods. The results clearly show that DTSCORE is more accurate than all the other methods we studied. Finally, we report the results of DTSCORE on a real dataset. SUPPLEMENTARY INFORMATION: http://www.lirmm.fr/w3ifa/MAAS/

Chromosome Mapping↗
PubMed1996

Expert systems for the evaluation of data quality for establishing the Recommended Dietary Allowances.

In view of the important role that nutrient intake assessments play in establishing the Recommended Dietary Allowances (RDAs), the quality of food composition data must be assured for accuracy and representativeness. Assurance of data quality requires the definition of critical parameters in the data generation process and the evaluation of specific data for foods and components according to these parameters. An expert systems approach for evaluating the quality of analytical data has been developed by scientists at the Beltsville Human Nutrition Research Center to determine the quality of food composition data for five parameters: sampling plan, sample handling, number of samples, analytical method and analytical quality control. A rating scale for each parameter was developed with 0 representing poor or inadequately documented data and 3 representing optimal data. Specific criteria for each parameter and rating have been developed and incorporated into expert systems software to facilitate the objective assignment of ratings for each data source by the reviewer. After all ratings for a specific food-nutrient combination are assigned, the system calculates a composite score called the "confidence code" which indicates to the user the relative level of confidence in the data. By identifying and rating the important steps in the data generation process, one can begin to partition the possible sources of error or variability in the process. Limitation of the data set relative to specific purposes (e.g., setting the RDAs) can be identified. The evaluation process can provide the basis for focussed research to improve the most critical areas of the data generation process. A similar process could be established to evaluate the quality of analytical data for clinical measurements used to establish the RDAs.

Documentation↗
PubMed1982

Computerized approach to verifying study population data in occupational epidemiology.

IN a previous paper a method was presented for verifying the completeness of occupational study populations independently of company-held records. The basis for the verification scheme was the Employers Quarterly Report on Earnings (Internal Revenue Service Form 941) that is submitted to the IRS each quarter of every year for all employees on a company payroll. In employing the verification scheme two approaches can be taken in determining how many and which quarterly reports are selected: (1) If the work force is large and/or many years are surveyed, a probability sample of years and quarters within years can be selected, allowing inferences to be made with respect to the entire study population. (2) If the number of survey years and/or the size of the work force is sufficiently small, copies of all quarterly returns for each survey year can be requested thus allowing a comprehensive check for completeness to be conducted. Te verification method described in the previous paper concentrated primarily on the first-mentioned approach. The second approach is herein being dealt with as well as a computerized method for verifying the completeness of study populations. In addition a new computerized method is described that utilizes the quarterly reports as an unbiased data base for checking the accuracy of certain work history data as developed from company records. An application of the computerized methods is given using data from a recent historical-prospective study of chemical production workers.

Computers↗
PubMed1998

Structure refinement against synchrotron Laue data: strategies for data collection and reduction.

The synchrotron Laue technique has been applied to high-resolution structure refinement of the ribotoxin, restrictocin [Yang & Moffat (1996). Structure, 4, 837-852]. By employing carefully designed data-collection strategies and the data-reduction algorithms incorporated in the software system LaueView [Ren & Moffat (1995a). J. Appl. Cryst. 28, 461-481; Ren & Moffat (1995b). J. Appl. Cryst. 28, 482-493], a set of high-resolution Laue data with a completeness and accuracy comparable to excellent monochromatic data was obtained. Through detailed comparison with the monochromatic data and electron-density maps derived from the Laue data, optimum data-collection and reduction strategies were identified and the application of Laue diffraction techniques to conventional crystallographic refinement was demonstrated.

Algorithms↗
PubMed1996

Rules for collection of clinical data: the eight Rs.

Many reports in medical journals give advice on statistical analysis of data collected in clinical studies. The terms used are statistical, and clinicians often ponder how their data stand up to these analyses. Eight simple, easy to remember words are suggested that will help clinicians both to interpret their own data and to assess the accuracy of presented or published data.

Data Collection↗
PubMed2005

Determination of the interfacial water content in protein-protein complexes from free energy simulations.

The question as to how many tightly or weakly bound water molecules are located in interfaces between protein-protein complex constituents is addressed from a phase equilibrium point of view by developing a theory in the canonical ensemble. A fast method based on free energy simulations is described for computing the number of water molecules in the interface regions. Results are given for 211 interfacial cavities of 26 antigen-antibody complexes for which experimentally determined structures are found in the Protein Data Bank. The accuracy of the method is assessed and the computational water content is compared with experimental data, revealing the amount of water molecules not resolved by experimental approaches.

Antigen-Antibody Complex↗
PubMed1991

Mothers' reports of childhood vaccinations and infections and their concordance with general practitioner records.

Mothers of 294 children aged 3-9 years were interviewed about their child's previous history of vaccinations and infections. The study group comprised healthy children selected at GP surgeries (n = 136) and those hospitalized for both minor and serious conditions (n = 168). The results evaluate the entire study group for the pattern of reporting vaccinations and infectious episodes under three years of age, comparing two different data sources-mothers' reports and GP records. Maternal recall accuracy is formally tested (Kappa statistic) for agreement with GP records. For vaccination history the results indicate that mothers and GPs are inadequate data sources, and suggest use of computerized health district records to improve data accuracy. Major differences on infectious history were evident for two types of questions-closed for specific infections and open-ended for 'other infections'. Specific infections (e.g. measles) were systematically over-reported by mothers compared with GP records, but mothers failed to 'time' the event. Concordance for 'other infections' was also poor, but, by contrast, GPs systematically over-recorded this range of infections, indicating substantial inaccuracy in mothers' recall. The authors suggest that GP records should be the preferred source of data for these 'other' infectious episodes, especially under one year of age. Improved questionnaire design would elicit more accurate maternal reports on specified infections for which a GP may well not be consulted and corroboration would be impossible.

Case-Control Studies↗
PubMed2001

The accuracy and effectiveness of routine population screening with mammography, prostate-specific antigen, and prenatal ultrasound: a review of published scientific evidence.

OBJECTIVE: To review published data regarding the accuracy and effectiveness of three screening tests: mammography, prostate-specific antigen (PSA), and prenatal ultrasound. METHODS: Published evidence regarding the accuracy and effectiveness of the three tests was collected by computerized literature search and supplemented by manual review of relevant bibliographies. RESULTS: Screening mammograms lower breast cancer mortality by about 20%. Most data come from women aged 50-64 years; women aged 40-49 years may also benefit, but the absolute risk reduction is lower. Up to 1,500 to 2,500 women must undergo screening to prevent one death from breast cancer. Mammograms miss approximately 12% to 37% of cancers, generate false-positive results, and cause anxiety while abnormal results are evaluated. PSA screening can detect 80% to 85% of prostate cancers but has a high false-positive rate. There is little direct evidence that early detection reduces morbidity or mortality. Indirect evidence includes a trend toward earlier stage tumors and steadily declining mortality rates in geographic areas where PSA screening has become common. Potential harms include the morbidity associated with evaluating abnormal results, and complications from treatment (e.g., impotence, incontinence). The overall balance of benefits and harms remains uncertain in the absence of better evidence. Prenatal ultrasound may reduce perinatal mortality, primarily through elective abortions for congenital anomalies, but does not appear to lower live birth rates. Although ultrasound has no proven effect on neonatal morbidity, it provides more accurate estimates of gestational age that prevent unnecessary inductions for post-term pregnancy. Screening detects multiple gestations, congenital anomalies, and intrauterine growth retardation, but direct health benefits from having this knowledge are unproved. Ultrasound has both positive and negative psychological effects on parents. The scans do not appear to harm childhood development. CONCLUSIONS: Even for the most established screening tests, the appropriateness of routine testing depends on subjective value judgments about the quality of supporting evidence and about the trade-offs between benefits and harms. Individuals, clinicians, policy makers, and governments must weigh the evidence in light of these values and the constraints imposed by available resources.

Adult↗
PubMed2007

Toward optimal recording of surgical complications: concurrent tracking compared to the discharge data set.

BACKGROUND: Information extracted from the hospital discharge data set is used increasingly for outcomes research and for benchmarking hospital and provider performance. The accuracy of these data in detecting vascular complications has never been validated. METHODS: We compared morbidity and mortality data derived from the hospital discharge data set to similar data recorded concurrently by our Surgical Activity Tracking System (SATS) for 1 year on the vascular surgery service. RESULTS: Of 798 total admissions, no complications were detected by either system in 598 admissions (75%). In 200 admissions (25%), there were 335 complications, including 24 deaths (3.0%), that occurred either in-hospital or within 30 days of the date of operation or the date of discharge for nonoperative admissions. Of the 335 complications, 180 (53.7%) were recorded by both systems; the SATS missed 59 complications recorded in the hospital discharge data set (17.6%), whereas the hospital discharge data set missed 96 complications recorded in the SATS (28.7%, P = .003). Of the 289 in-hospital complications, the SATS recorded 230 (79.5%), whereas the hospital discharge data set recorded 229 (79.2%). Of the 24 deaths, the hospital discharge data set missed 6 that occurred after discharge but within the 30-day reporting period CONCLUSIONS: Both systems are not completely accurate for tracking inpatient complications. The SATS was more representative than the hospital discharge data set in capturing 30-day morbidity and mortality. An amalgamation of the 2 systems would provide more optimal tracking of complications.

Databases, Factual↗