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At least 1,315 records · Page 73Linked to original sources
PubMed2005

Indirect cost assessment in patients with rheumatoid arthritis (RA): comparison of data from the health economic patient questionnaire HEQ-RA and insurance claims data.

OBJECTIVE: To render information on the accuracy of patient-reported indirect cost data compared with payer-derived data of the real indirect costs on a patient-by-patient basis concerning disease-related productivity losses in rheumatoid arthritis (RA). METHODS: The assessment of indirect cost data was part of a clinical, multicenter, randomized RA trial. A total of 234 patients of working age with a diagnosis of RA (according to 1987 American College of Rheumatology criteria) were recruited. Demographics of the cohort were mean age 53 years, mean disease duration 8 years, 76% were women, and all had membership in the regional statutory health insurance plan. Every 3 months corresponding indirect cost data were derived for the cohort from a health economic questionnaire for cost assessment in patients with RA and the payer's database over a period of 18 months. Comparative statistical analyses were performed between patient-reported and insurance claims data. RESULTS: The mean annual productivity losses due to sick leave amounted to 14 and 17 days per patient (questionnaire versus payer data), and productivity losses due to work disability amounted to 3 days (both); monetary valuation renders overall costs of 1,240 and 1,590, respectively. The difference of 17% in overall productivity losses is not significant. Comparison of productivity losses reveals a strong correlation of r = 0.83 in those due to sick leave and of kappa = 0.84 in those due to work disability between questionnaire and payer data. CONCLUSION: The comparison of questionnaire and payer data shows that RA patients report their productivity losses adequately. Indirect cost assessment should therefore be included in further RA trials and observational studies.

Adolescent↗
PubMed2000

A systematic review of troponin T and I for diagnosing acute myocardial infarction.

OBJECTIVE: Elevations of serum troponin T and I values are being used to diagnose acute myocardial infarction (AMI) and to rule out the condition in patients before their discharge from the emergency department (ED). However, the sensitivity and specificity of these tests vary considerably. Our goal was to systematically review the data on the accuracy of troponin T and I for the diagnosis of AMI in the ED. SEARCH STRATEGY: We searched the MEDLINE database using the following strategy: troponin (text word) and diagnosis (medical subject heading [MeSH]) or troponin/diagnostic use (MeSH). The references of articles meeting our inclusion criteria were searched for additional articles. SELECTION CRITERIA: We evaluated each study for quality. Only prospective blinded cohort studies with an adequate reference standard were included in the analysis. DATA COLLECTION/ANALYSIS: Data from each study were abstracted by 2 investigators. We graphed sensitivity and specificity for different points in time from arrival in the ED or from the onset of pain and calculated summary estimates when appropriate and possible. MAIN RESULTS: Sensitivity increases for both troponin T and I from 10% to 45% within 1 hour of the onset of pain (depending on the cutoff) to more than 90% at 8 or more hours. Specificity declines gradually from 87% to 80% from 1 to 12 hours after the onset of chest pain for troponin T and is approximately 95% for troponin I. The peak abnormal value in the first 24 hours after admission to the ED has an area under the receiver operating characteristic curve of 0.99 and is very useful at ruling out AMI if negative. CONCLUSIONS: Although troponin T and I values are useful tools for the diagnosis of AMI, they must be interpreted according to the number of hours from the onset of chest pain. The test is particularly useful at ruling out MI when the value is negative at 8 or more hours after the onset of chest pain.

Adult↗
PubMed1984

Peripheral arterial disease diagnosed with high-count-rate radionuclide arteriography.

Thirty-seven patients with peripheral vascular disease involving the legs were studied with first-pass peripheral radionuclide arteriography (RNA) and contrast arteriography to determine whether RNA could be used to evaluate perfusion of the toes. Data were acquired for 100 seconds using a multicrystal gamma camera following bolus injection of 30-35 mCi (1,110-1,295 MBq) of Tc-99m-labeled albumin during reactive hyperemia. Peripheral time-activity curves were examined and the time required for activity to decline to 75% of peak activity ( T75 ) was recorded. When an abnormal RNA was defined as T75 greater than or equal to 50 seconds, sensitivity was 92%, positive predictive accuracy 100%, and negative predictive accuracy 75%. These data suggest that peripheral RNA of the toes is a reliable, noninvasive procedure for evaluation of peripheral arterial disease; it can be valuable as a screening test prior to contrast arteriography as well as for follow-up.

Adult↗
PubMed2003

Focal hepatic lesions: detection and characterization with combination gadolinium- and superparamagnetic iron oxide-enhanced MR imaging.

PURPOSE: To compare gadolinium- and superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging for detection and characterization of focal hepatic lesions when different contrast agent administration sequences are used. MATERIALS AND METHODS: Unenhanced, dynamic gadolinium-enhanced, and SPIO-enhanced hepatic MR images were obtained in 134 patients. SPIO-enhanced MR imaging was performed immediately after gadolinium-enhanced dynamic MR imaging in 50 patients, 1 day after gadolinium-enhanced dynamic MR imaging in 40 patients, and before gadolinium-enhanced dynamic MR imaging in 44 patients. Two radiologists independently reviewed the gadolinium image set (unenhanced and gadolinium-enhanced dynamic MR images) and the SPIO image set (unenhanced and SPIO-enhanced MR images) in random order. Lesion detection sensitivity and lesion characterization accuracy were compared by analyzing the area under the receiver operating characteristic curve (Az). RESULTS: Overall lesion detection accuracy for pooled data was significantly higher with the SPIO set (Az = 0.903) than with the gadolinium set (Az = 0.857) (P <.05). When hypovascular lesions were excluded, the detection rate was similar with the two sets. When hepatocellular carcinomas were excluded, the detection rate was significantly higher with the SPIO set (P <.01). Readers were more accurate in differentiating benign from malignant lesions with the gadolinium set (Az = 0.915) than with the SPIO set (Az = 0.847) (P <.01). Detection accuracy tended to be better with the images obtained after the second contrast agent was used. CONCLUSION: Hypovascular lesion detection was better with SPIO-enhanced MR images than with gadolinium-enhanced MR images. Detection and characterization of hypervascular lesions were improved with gadolinium-enhanced MR images.

Adult↗
PubMed1998

Dual-isotope protocol for indium-111 capromab pendetide monoclonal antibody imaging.

OBJECTIVE: A dual-isotope imaging protocol using 99mTc-labeled red blood cells with 111In capromab pendetide monoclonal antibody imaging for detective and localizing nodal metastasis in prostate cancer is described. METHODS: This protocol involves a single SPECT acquisition that is less time consuming and more comfortable for the patient than the currently recommended method, which requires two separate SPECT acquisitions performed on different days. RESULTS: Forty patients were studied with the dual-isotope protocol. Preliminary data suggest increased accuracy compared with the single-isotope technique. CONCLUSION: The dual-isotope technique assures the precise image registration needed for accurate comparison of blood pool and pelvic lymph node activity that is required for confident and accurate image interpretation.

Antibodies, Monoclonal↗
PubMed2004

Predicting postoperative intraocular lens position and refraction.

PURPOSE: To predict the postoperative IOL position and refraction as accurately as possible independent of individualization of the parameters. SETTING: Universitats-Augenklinik, Mainz, Germany, and Vienna, Austria. METHODS: One patient cohort (189 eyes, Vienna) was used to calibrate the prediction method, which was then applied to a second cohort (65 eyes, Mainz). All calculations were based on consistent numerical ray tracing of the pseudophakic eye using the original manufacturer's intraocular lens (IOL) data (radii, thickness, refractive index). A new algorithm to predict IOL position was developed. Ultrasound (US) axial lengths were calibrated relative to partial coherence interferometry (PCI). Corneal radii extracted from topography were checked against radii measured with the IOLMaster (Zeiss) and by Littmann keratometry. RESULTS: Zero mean prediction errors for IOL position and refraction were obtained without adjusting the parameters and with PCI lengths or US lengths calibrated relative to the PCI values. There was no significant loss of accuracy of US data compared to PCI data. Corneal radii extracted from topography were slightly but statistically significantly different from the Littmann values, and they were more accurate than the latter with respect to prediction error. The measured mean central IOL position (distance from posterior corneal surface) for all IOL types was 4.580 mm, a value very close to the mean recalculated from A-constants (4.587 mm). The difference in the individual central IOL position relative to the mean value depended only linearly (ie, no higher orders such as square or cubic are needed) on axial length, with the mean central IOL position as a free parameter. This parameter should be 4.6 +/- 0.2 mm (the same value as independently measured or recalculated) to obtain zero steepness of the prediction error as a function of axial length, producing zero bias for long and short eyes. CONCLUSIONS: Calculation errors from formulas and confusing adjusting parameters can be avoided if calculations and measurements are performed on a clear and simple physical basis. Nevertheless, an individual prediction error, typically 0.5 to 1.0 diopter, seems to be unavoidable.

Adult↗
PubMed2003

Unruptured intracranial aneurysms.

Between 3.6 and 6% of the population harbour an unruptured intracranial aneurysm. Risk of rupture is related to aneurysm site and size and whether or not the patient has already had a subarachnoid haemorrhage (SAH) from another aneurysm. In ISUIA 2, the rupture rate for anterior circulation aneurysms<7mm was 0% per year in patients with no prior SAH, and 0.3% per year in patients with previous SAH; 7-12mm aneurysms, 0.5% per year (both groups); 13-24mm aneurysms, 3% per year; and giant aneurysms 8% per year. Rupture rate for posterior circulation aneurysms is higher at all sizes:<7mm was 0.5% per year in subjects with no prior SAH, 0.7% in those with prior SAH; 7-12mm, 3% per year; 13-24mm, 3.7% per year; and giant aneurysms, 10% per year. Non-invasive tests like contrast enhanced magnetic resonance angiography (MRA) and multislice computed tomographic angiography (CTA) are alternatives to intra-arterial digital subtraction angiography (IADSA) to detect aneurysms. Although these are promising techniques, the quality of data testing their accuracy remains limited and single slice CTA and time-of-flight MRA are poorer at detecting aneurysms<5mm diameter, which account for up to 1/3 of unruptured aneurysms. For ruptured aneurysms, the only large scale randomised controlled trial comparing surgical and endovascular treatment (ISAT) by coiling, resulted in an absolute 8.8% reduction (updated figure as of June 2003 for 1888 patients) in death or dependency at 1 year compared with surgical clipping. For unruptured aneurysms, the best available data so far comparing coiling and clipping is from the prospective (but non-randomised) arm of ISUIA. Elective surgical clipping had combined morbidity and mortality at 1 year of 12.2% versus 9.5% for coiling, although the groups were not matched with more high risk patients in the endovascular treatment cohort. Nevertheless these data are encouraging for future randomised trials of elective coiling versus clipping for asymptomatic aneurysms, in particular as the unproven long-term durability of coiling treatment and the fact that complete aneurysm occlusion is not always achieved remain obstacles to its wider use in unruptured aneurysms. There is an increased risk of SAH in relatives of patients with SAH (highest in those with two or more first degree relatives affected), but most SAH is sporadic and therefore the balance of available evidence indicates that mass screening for aneurysms is not cost effective. There may be a limited role for investigation of high-risk subgroups and ideally such screening should be tested in a randomised trial. The avoidance and active management of vascular risk factors should also be part of the management of at risk subjects.

Aneurysm, Ruptured↗
PubMed1997

Practical operation of a biaxial goniometer at the wrist joint.

The objectives of this study were (a) to determine errors in wrist angle measurements from a commercially available biaxial electrogoniometer and (b) to develop a calibration routine in order to correct for these errors. Goniometric measurements were collected simultaneously with true angular data using a fixture that allowed wrist movement in one plane while restricting motion in the orthogonal plane. These data were collected in two sets of trials: flexion/extension with radial/ulnar deviation restricted, and radial/ulnar deviation with flexion/extension restricted. During these trials, we studied discrete 30 degrees increments of forearm rotation. The results showed the expected cross talk and zero drift errors during forearm rotation. The application of mathematical equations that describe the effect of goniometer twist resulted in significant error reduction for most forearm rotations. The calibration technique employs both a slope and a displacement transformation to improve the accuracy of angular data. The calibration technique may be used on data collected in the field if forearm rotation is measured simultaneously with the goniometer data.

Calibration↗
PubMed1999

Diagnostic accuracy of oropharyngeal cultures in infants and young children with cystic fibrosis.

The objective of this study was to assess the diagnostic accuracy of oropharyngeal (OP) cultures relative to simultaneous bronchoalveolar lavage (BAL) cultures in very young children with CF, and to examine the effects of bacterial density, age, and study cohort on diagnostic accuracy. Respiratory culture data were analyzed from three independent, prospective studies involving simultaneous collection of 286 OP and BAL cultures from 141 children with CF <5 years of age. For predicting any growth of Pseudomonas aeruginosa (Pa) from the lower airway in subjects </=18 months of age (mean age, 8 +/- 5 months), OP cultures had a sensitivity of 44% (95% CI 14%, 79%), specificity of 95% (90%, 99%), positive predictive value of 44% (14%, 79%), and negative predictive value of 95% (90%, 99%). Diagnostic accuracy was similar for Haemophilus influenzae (Hi). Specificity was significantly lower for Staphylococcus aureus (Sa). Sensitivity for all organisms improved if a positive lower airway culture was defined as >/=10(3) or >/=10(5) cfu/mL. Specificity for Pa declined significantly with increasing age. In children with CF <5 years of age, the specificity and negative predictive value of OP cultures for Pa are high, while the sensitivity and positive predictive value are poor. Thus, in this age range, a negative throat culture is helpful in "ruling out" lower airway infection with Pa. However, a positive culture does not reliably "rule in" the presence of Pa in the lower respiratory tract. These findings may have implications for study design and interpretation as well as clinical management of young children with CF.

Bacterial Infections↗
PubMedDate not supplied

Improving diagnostic accuracy using an evidence-based nursing model.

PURPOSE: To propose an evidence-based model (EBM) to improve diagnostic accuracy in nursing. DATA SOURCES: Published literature, experience, and expertise of authors. DATA SYNTHESIS: Using an EBM directs clinicians on how to use the best available evidence from the literature to determine the best fit between cues and diagnoses, integrate this evidence with clinician expertise and patient preferences, and conduct a self-evaluation of the process. CONCLUSIONS: Use of an EBM to teach nurses how to ask relevant diagnostic questions and provide a framework for nurse educators to teach evidenced-based practice may lead to developing more competent diagnosticians and improving diagnostic accuracy in nursing.

Clinical Competence↗
PubMed1992

The use of exit interviews in health service facilities.

Exit Interviews, also known as termination or separation interviews, are conducted in some hospitals and other health service agencies as a routine procedure when staff are ending their period of employment. The major purpose of these interviews is to elicit data regarding the employee's working experience in the organization and hence identify those factors that enhance retention of staff, for example, job satisfaction, study opportunity, challenging milieu, and those that are contributory factors to the decision to resign, such as, dissatisfaction due to poor standards of care becoming the norm and lack of autonomy in planning and implementing nursing care. As a recent study indicated, the hierarchical level of the Exit Interviewer could have a significant effect on the amount and accuracy of the data so obtained. While applicable to all departments of a facility, comments herein are largely concerned with nursing and are based on a thesis by the author.

Humans↗
PubMed1993

How valuable is feedback of information on hospital referral patterns?

OBJECTIVES: To determine general practitioners' responses to and explanations for variation in rates of referral to hospital and how feedback of data on rates of referral could be used to facilitate practices in auditing their own referral behaviour. DESIGN: Visits by audit facilitators to general practices after feedback of details of rates of referral to hospital derived from annual reports in general practice. SETTING: 92 general practices in East Anglia. RESULTS: General practitioners judged that access to specialist care, the individual skill of general practitioners, patient demand, and fear of litigation were major determinants of referral behaviour. Because there was widespread scepticism about the accuracy of the data on which the feedback was based and because there is no clear relation between rates of referral and quality of care, it was extremely difficult to encourage doctors to use the feedback as a basis for auditing their own hospital referrals. CONCLUSION: If general practitioners are to contribute meaningfully to monitoring future changes in referral patterns it will be essential to develop reliable information systems in which doctors have confidence. Furthermore, audits need to be based on analysis of clinical cases rather than on rates of referral.

Attitude of Health Personnel↗
PubMed2005

Fast, simple, and validated gas chromatographic-mass spectrometric assay for quantification of drugs relevant to diagnosis of brain death in human blood plasma samples.

In addition to total anamnesis, one of the important aspects in diagnosis of brain death is the exclusion of effective plasma concentrations of drugs that might mimic brain death. A minimum consensus for toxicological analysis in this context includes relevant analytes (thiopental, pentobarbital, methohexital, phenobarbital, diazepam, nordazepam, and midazolam) and proposes limits of quantification. Propofol is another relevant drug. After liquid-liquid extraction of 200 microL of plasma using 50 microL of a solution of deuterated internal standards in butyl acetate and 50 microL of butyl acetate, 2 microL of the organic phase was analyzed by gas chromatography-mass spectrometry using selected-ion monitoring mode. Validation included the parameters selectivity, calibration model, precision and accuracy, and extraction efficiency. Accuracy and precision data obtained using 6-point and 1-point calibration were compared. The abovementioned analytes were separated within 10 minutes and sensitively detected. No interfering peaks were observed in blank samples from 10 different sources. The linearity ranges were 0.5-6 mg/L for propofol, 0.25-10 mg/L for pentobarbital and thiopental, 0.125-10 mg/L for methohexital, 2.5-50 mg/L for phenobarbital, 0.05-2.5 mg/L for diazepam and nordazepam, and 0.01-0.5 mg/L for midazolam. Extraction efficiency ranged from 85% to 111%. The acceptance criterion for accuracy and precision (99% confidence interval of measured mean within +/-50% of target value) was fulfilled for all analytes, even with 1-point calibration using a calibrator close to the center of the linearity range. The assay was applied to analysis of real brain death cases. In conclusion, the described assay allowed fast and reliable determination of analytes relevant to diagnosis of brain death, and 1-point calibration kept the workload low.

Brain Death↗
PubMed1992

Live animal measurement of carcass traits by ultrasound: assessment and accuracy of sonographers.

The establishment and evaluation of an assessment system to accredit sonographers for measuring the carcass traits of subcutaneous fat depths and longissimus muscle area (LMA) on potential breeding animals by real-time ultrasound is described. Repeatability of operators, variation between the animal's left and right sides, and variations in technique were assessed from measurements and repeat measurements of 30 cattle by up to eight operators at three testing sessions. Accuracy of carcass data was determined by repeatability of measurements, variability between measurers, between left and right sides of the carcass, and variation due to handling and dressing procedures. Correlations with carcass data averaged .92 for rump fat, .90 for rib fat, and .87 for LMA. Residual SD averaged .81 mm, .88 mm, and 5.1 cm2. A very experienced sonographer can measure LMA only marginally less accurately than it can be measured on the carcass. In Session 3, the SE between repeat fat measurements for accredited sonographers averaged .43 mm, indicating that fat depths can be measured more accurately, but when comparing measurements from different operators, adjustments may be required for differences in technique, otherwise overall accuracy will be about the same, approximately 1 mm. Scanned rump fat measurements were consistently approximately 20% higher than on the chilled, hanging carcass 24 h after slaughter; after applying the standard correction factor of 1.17, LMA measurements were similar. Scan and carcass rib fat measurements were similar for animals with less than or equal to 10 mm of fat cover, above which carcass measurements tended to be higher.

Accreditation↗
PubMed2001

Automatic signal classification in fluorescence in situ hybridization images.

BACKGROUND: Previous systems for dot (signal) counting in fluorescence in situ hybridization (FISH) images have relied on an auto-focusing method for obtaining a clearly defined image. Because signals are distributed in three dimensions within the nucleus and artifacts such as debris and background fluorescence can attract the focusing method, valid signals can be left unfocused or unseen. This leads to dot counting errors, which increase with the number of probes. METHODS: The approach described here dispenses with auto-focusing, and instead relies on a neural network (NN) classifier that discriminates between in and out-of-focus images taken at different focal planes of the same field of view. Discrimination is performed by the NN, which classifies signals of each image as valid data or artifacts (due to out of focusing). The image that contains no artifacts is the in-focus image selected for dot count proportion estimation. RESULTS: Using an NN classifier and a set of features to represent signals improves upon previous discrimination schemes that are based on nonadaptable decision boundaries and single-feature signal representation. Moreover, the classifier is not limited by the number of probes. Three classification strategies, two of them hierarchical, have been examined and found to achieve each between 83% and 87% accuracy on unseen data. Screening, while performing dot counting, of in and out-of-focus images based on signal classification suggests an accurate and efficient alternative to that obtained using an auto-focusing mechanism.

Amniotic Fluid↗
PubMedDate not supplied

The use of the Minimum Data Set to identify depression in the elderly.

OBJECTIVE: To determine whether depression in the elderly in institutionalized settings could be identified using the mood indicators in the Minimum Data Set (MDS) 2.0 (Section E1, Items A-P). DESIGN: Descriptive study. SETTING: Three nursing homes in the southeastern part of the country. PARTICIPANTS: Residents aged 65 and above. MEASUREMENTS: The items in "Indicators of Depression, Anxiety and Sad Mood" on the MDS 2.0 were used to identify observable features of depression in the elderly. The Cornell Scale for Depression in Dementia (CSDD) was used to validate the MDS indicators. Consensus analysis, which controls raters' bias, raters' ability, and item difficulty, was used to analyze data. RESULTS: No depressive patterns were detected using the MDS indicators. On the CSDD, distinct depressive features were identified: anxiety, sadness, lack of reaction to pleasant events, irritability, agitation, multiple physical complaints, loss of interest, appetite loss, and lack of energy. CONCLUSION: The incongruent findings on the MDS indicators the CSDD may be reflective of the assessment process used with the MDS rather than its ability to identify features of elderly depression. The practice of allowing nondirect caregivers to complete the MDS may have serious implications for the accuracy of the data collected.

Affect↗
PubMed1991

Interlaboratory variability in serum lipid measurements.

Identification of elevated blood cholesterol has become a priority in the effort to reduce coronary heart disease. Previous data indicate that considerable laboratory variability in lipid testing exists in the United States. To determine the interlaboratory variability of serum lipid measurements in the Little Rock area, split serum samples from three subjects were sent to ten area laboratories. The average coefficient of variation among the ten local laboratories was 3.20% for total cholesterol, 9.46% for HDL-cholesterol, 7.73% for triglycerides, and 5.95% for calculated LDL-cholesterol. The results indicate that clinicians cannot assume that adequate standardization for lipid determinations exists for all laboratories. Without accuracy and precision data for the specific laboratory, caution should be used in the strict application of guidelines for classification and treatment of patients with abnormal serum-lipid measurements.

Arkansas↗
PubMed1996

Assessment of protein fold predictions from sequence information: the predicted alpha/beta doubly wound fold of the von Willebrand factor type A domain is similar to its crystal structure.

The fold of the von Willebrand Factor type A domain (vWF-A) was predicted to be similar to an alpha/beta doubly wound fold in the GTP-binding domain of ras-p21, despite the lack of sequence or functional similarity. This was subsequently confirmed by the vWF-A crystal structure from complement receptor type 3. The prediction is now reviewed. The vWF-A secondary structure was predicted with 62 to 75% accuracy and 12 of the 13 secondary structure elements were identified correctly. Accessibility predictions were 69 to 71% accurate. The fold recognition analysis was confirmed, but was much improved by averaging the results from 70 complete vWF-A sequences. The related folds of ras-P21 and flavodoxin scored highly. In addition, both the mapping of the predicted vWF-A secondary structure elements with those in 12 known alpha/beta folds and two Asp residues at the C-terminal ends of two adjacent beta-strands matched well with ras-p21 and flavodoxin. The predicted Mg(2+)-binding site, two disulphide bridges and the secondary structure topology were largely accurate. The exception is the reversal of a beta-hairpin at one end of the central beta-sheet. We conclude that non-homologous folds with dissimilar functions can be predicted from sequence data with reasonable accuracy, and that the accuracy in this case was principally limited at the periphery of the fold.

Amino Acid Sequence↗