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PubMed2002

JJ1017 committee report: image examination order codes--standardized codes for imaging modality, region, and direction with local expansion: an extension of DICOM.

The digital imaging and communications in medicine (DICOM) standard includes parts regarding nonimage data information, such as image study ordering data and performed procedure data, and is used for sharing information between HIS/RIS and modality systems, which is essential for IHE. To bring such parts of the DICOM standard into force in Japan, a joint committee of JIRA and JAHIS established the JJ1017 management guideline, specifying, for example, which items are legally required in Japan, while remaining optional in the DICOM standard. In Japan, the contents of orders from referring physicians for radiographic examinations include details of the examination. Such details are not used typically by referring physicians requesting radiographic examinations in the United States, because radiologists in the United States often determine the examination protocol. The DICOM standard has code tables for examination type, region, and direction for image examination orders. However, this investigation found that it does not include items that are detailed sufficiently for use in Japan, because of the above-mentioned reason. To overcome these drawbacks, we have generated the JJ1017 code for these 3 codes for use based on the JJ1017 guidelines. This report introduces the JJ1017 code. These codes (the study type codes in particular) must be expandable to keep up with technical advances in equipment. Expansion has 2 directions: width for covering more categories and depth for specifying the information in more detail (finer categories). The JJ1017 code takes these requirements into consideration and clearly distinguishes between the stem part as the common term and the expansion. The stem part of the JJ1017 code partially utilizes the DICOM codes to remain in line with the DICOM standard. This work is an example of how local requirements can be met by using the DICOM standard and extending it.

Diagnostic Imaging↗
PubMed2005

The effects of violating standard item writing principles on tests and students: the consequences of using flawed test items on achievement examinations in medical education.

The purpose of this research was to study the effects of violations of standard multiple-choice item writing principles on test characteristics, student scores, and pass-fail outcomes. Four basic science examinations, administered to year-one and year-two medical students, were randomly selected for study. Test items were classified as either standard or flawed by three independent raters, blinded to all item performance data. Flawed test questions violated one or more standard principles of effective item writing. Thirty-six to sixty-five percent of the items on the four tests were flawed. Flawed items were 0-15 percentage points more difficult than standard items measuring the same construct. Over all four examinations, 646 (53%) students passed the standard items while 575 (47%) passed the flawed items. The median passing rate difference between flawed and standard items was 3.5 percentage points, but ranged from -1 to 35 percentage points. Item flaws had little effect on test score reliability or other psychometric quality indices. Results showed that flawed multiple-choice test items, which violate well established and evidence-based principles of effective item writing, disadvantage some medical students. Item flaws introduce the systematic error of construct-irrelevant variance to assessments, thereby reducing the validity evidence for examinations and penalizing some examinees.

Choice Behavior↗
PubMed2006

A method to calculate tissue impedance through a standard bipolar pacing lead.

UNLABELLED: The transthoracic impedance (T) and its variations may be estimated through the measurement of the electrical impedance between the can and the right ventricular coil of a defibrillation lead. This method may allow the monitoring of fluid overload before a heart failure attack. Aim of this study was to validate in vitro a method to calculate T in case of a standard bipolar pacing lead, by performing 3 measurements: standard unipolar impedance from the tip (Zuni-tip); unipolar impedance from the ring (Zuni-ring); standard bipolar impedance (Zbip). The formula we used is derived from the standard equivalent circuit of a pacing system: [Formula: see text] T represents the tissue impedance between the can and the electrodes of the lead. To validate the method we used a saline solution and 3 different pacing leads manufactured by Vitatron (Vitatron BV, Arnhem, The Netherlands): Impulse II (high impedance lead), Crystalline ActFix (screw-in lead), Brilliant S+ (VDD single-lead). The measured values of the saline solution impedance were compared to the values calculated through the formula. RESULTS: The calculated impedance of the solution, evaluated through the proposed formula, is reliable independently of the electrode used and highly correlated to the corresponding measured values (R>0.9). CONCLUSION: Tissue impedance may be calculated from standard unipolar and bipolar impedance measurements with a standard bipolar pacing lead.

Electric Impedance↗
PubMed2004

Student development and ownership of ethical and professional standards.

Ethics and professional conduct are vital to civil engineering undergraduate curricula. Many programs struggle to ensure that students are given an adequate exposure to and appreciation of ethical and professional conduct issues. This paper describes a two-part ethics/professionalism project used in a senior-level course taught at the University of Arkansas. Initially, students scrutinize ethical canons and standards of professional conduct published by the American Society of Civil Engineers (ASCE) and the National Society of Professional Engineers (NSPE), and prepare an essay concerning the applicability of these standards. The second part of the project builds on the first: based on the opinion(s) generated in Part 1, students are asked to develop a set of canons or standards targeted specifically to the undergraduate student, and suggest processes for implementing those standards within the department. Project objectives include: (1) exposure to nationally-recognized ethical canons and standards of professional conduct; (2) personal formulation of ethical and professional standards; (3) skill enhancement for non-technical written communications. Feedback by students prior to and after the project indicates success in meeting all objectives. The feedback also indicates that for some students, definitions and applications of ethics and professionalism are being broadened to include more than academic honesty issues.

Arkansas↗
PubMed1995

Complete atrioventricular cardiac transplantation: improved performance compared with the standard technique.

BACKGROUND: There has been renewed clinical interest in an alternative technique to orthotopic cardiac transplantation involving six anastomoses: left pulmonary veins, right pulmonary veins, inferior vena cava, pulmonary artery, aorta, and superior vena cava (complete technique). In this study, the results of the complete technique are compared with those of the standard operation (ventricular transplantation with atrioplasty). METHODS: Dogs were used for ten acute standard and ten acute complete atrioventricular transplantations. There were no significant differences in the baseline cardiac function (preload-independent right and left ventricular recruitable stroke work), bypass times, and cardiac ischemic times between the two groups. RESULTS: After transplantation, sinus rhythm was preserved after all ten complete and after only one standard transplantation but no significant hemodynamic differences were observed. The right and left ventricular preload-independent recruitable stroke work in the complete group and the left ventricular preload-independent recruitable stroke work in the standard group were conserved after transplantation, but the right ventricular preload-independent recruitable stroke work decreased by 39% +/- 8% (p < 0.05) in the standard group. There was also a significant decrease in the rate of biventricular filling in the standard group after transplantation. CONCLUSIONS: Complete atrioventricular transplantation is a feasible alternative technique and conserves normal sinus rhythm. The ischemic and bypass times are comparable for both methods. The insignificant change in the rate of biventricular filling in the dogs undergoing the complete technique indicates right and left ventricular diastolic function may be conserved after transplantation.

Animals↗
PubMed1984

The Department of Defense Human factors standardization program.

The Department of Defense (DoD) Human Factors Standardization Program is the most far-reaching standardization programme in the USA. It is an integrated component of the overall DoD Standardization Program. While only ten major documents are contained in the human factors standardization area, their effects on human factors engineering programmes are profound and wide-ranging. Preparation and updating of the human engineering standardisation documents have grown out of the efforts of several military agencies, contractors, consultants, universities and individuals. New documents, engineering practice studies and revision efforts are continuously planned by the Tri-Service (Army, Navy, Air Force) Human Factors Standardization Steering Committee in collaboration with industry groups and technical societies. The present five-year plan and other standardisation documents are readily available for review and input by anyone with relevant interests. Human factors specialists and other readers of this journal may therefore influence the direction of the human factors standardisation programme and the content of its military specifications, standards and handbooks.

Journal Article↗
PubMed1983

Assay of AHF concentrates and standards: failure to eliminate variability with a monographed assay.

Previous calibration studies have shown a high interlaboratory variability in the potency of the proposed Office of Biologics (National Center for Drugs and Biologics, US-FDA) AHF standard relative to the 2nd International Standard for Factor VIII (Factor VIII:C) (WHO 73/552). This led to the formation of an Industry Collaborative Study group whose objective was to reduce the assay variability. The group, in collaboration with the Office of Biologics and the National Institute for Biological Standards and Control (UK), designed a study based on a monographed one-stage assay protocol, which specified all materials, assay methods, equipment, dilution technique, reagents, assay order, and calculation methodology. All participants received common reagents and samples, with the exception of substrate plasma. It was felt that substrate plasma could not be a common reagent in a monographed assay. However, each laboratory prepared substrate plasma according to the protocol. All data were analyzed by an independent statistical staff. Preparations assayed included two 10-donor plasma pools, the 2nd International Standard for Factor VIII (WHO 73/552), the proposed OoB Lot A internal standard, the participants' own house standards, and commercial AHF concentrate material. The results show a statistically insignificant reduction in the interlaboratory variability, but intralaboratory consistency was generally maintained. The study shows that monographing an assay for Factor VIII.

Adolescent↗
PubMed1986

Correlation of cerebrovascular disease standardized mortality ratios with dietary sodium and the sodium/potassium ratio among the Japanese population.

One thousand seventy-two 24-hr diet duplicate samples were collected from inhabitants of 49 regions in various parts of Japan during the winters of 1977-1981. An additional 238 samples were collected in an adjacent summer. The samples were analyzed for sodium (Na) and potassium (K) by flame atomic absorption spectrometry and for chloride (Cl) with a chloride counter. The winter-summer differences in Na, Cl, and Na/K were essentially negligible. When the regional means of Na, K, Cl, and Na/K were compared with the 1969-1978 standardized mortality ratios of each region, positive and significant correlations were observed between winter Na and the standardized mortality ratios for cerebrovascular disease (P less than 0.01), cerebral infarction (P less than 0.01), and subarachnoid hemorrhage (P less than 0.05) in both males and females. The correlation (P less than 0.01) with the cerebrovascular disease standardized mortality ratio was further confirmed by the values for 1978-1982. In the case of the Na/K ratio, the correlation with the standardized mortality ratio for each of the three diseases was significant for men (P less than 0.01 or 0.05, depending on the disease) but not for women (P greater than 0.05). Both Na and Na/K showed significant associations with the ischemic heart disease standardized mortality ratio in men (P less than 0.05) but not in women (P greater than 0.05). In contrast, no positive association was found between Na, K, Cl, or Na/K and standardized mortality ratios for diabetes mellitus, liver cirrhosis, tuberculosis, or liver cancer (P greater than 0.05). Current blood pressure did not appear to correlate with any of the Na, K, Cl, or Na/K measurements. The validity of the present observation is discussed.

Adult↗
PubMed1990

Comparison of three standards for quantifying occlusal loss of composite restorations.

Occlusal loss of resin composite in posterior restorations may be measured by assessing the exposure of cavity walls. The purpose of this study was to compare three standard scales used to quantify occlusal loss on stone replicas of posterior composites. Measurements of occlusal loss, on 60 stone replicas selected from two clinical studies, were obtained by comparison with three standard scales: L-calibrated die stone standards derived from clinical restorations (Leinfelder), M-dies with cylindrical incremental defects (M-L scale), and V-tooth-sized dies with restoration-like incremental defects (Vivadent). Evaluators with different dental and evaluating experience carried out the assessment using each standard on two different occasions. Differences among results obtained using the three standard scales were comparatively small when assessments were carried out by experienced evaluators. Use of the V standard consistently achieved a higher level of agreement by pairs of evaluators.

Composite Resins↗
PubMed1986

Setting standards of performance for program evaluations: the case of the teaching hospital general medicine group practice program.

Program evaluation is like research in its use of the scientific method. An important difference is that evaluations result in judgments of merit. What are the standards for making the judgments? Little attention has been paid to their selection and use. This article reports on how standards were set in an evaluation of the structure of fifteen of the nation's university hospitals who participated in the Teaching Hospital General Medicine Group Practice Program (sponsored by the Robert Wood Johnson Foundation). Many sources were used to select standards including a review of the literature, expert advice and actual data from two years of the programs's performance. Also, the standard-setting process was a participatory one in which all potentially competing views were provided with a forum for discussion. Finally, standards were set in advance of the collection of information, facilitating the selection of study designs and analysis techniques. Almost all project directors stated that the process helped them in program planning and gave them ideas for research and evaluation. Because standard-setting has mutual benefits, we recommend that it take place during program planning.

Evaluation Studies as Topic↗
PubMed1983

A grading system for bone marrow cytogenetics and its use as a standard for quality control.

A grading system has been developed to assess the quality of the results of bone marrow cytogenetic procedures. The results of 3 1/2 years use of this grading system are reported. This grading system is a satisfactory internal standard for quality control and is adaptable for use as an external standard. The use of such an internal standard will improve the performance of the cytogenetics laboratory and will validate the quality of the results of cytogenetic examination. The use of an external standard will stimulate the standardization and improvement of cytogenetic laboratory techniques and may be used to develop performance standards for accreditation of both bone marrow and other cytogenetic laboratories. Internal and external quality controls have been used in general medical laboratories for many years, and their use should be instituted by cytogenetic laboratories as well.

Bone Marrow↗
PubMed1994

A comparison study of the EF-18 agar/Hydrophobic Grid Membrane Filter (HGMF) method and the enzyme linked antibody (ELA)/HGMF method to the HPB standard method in the isolation of Salmonella.

As part of a comparative and collaborative study of rapid methods for the detection of Salmonella and the standard Health Protection Branch (HPB) method, six Federal and Provincial Laboratories compared the EF-18 agar/Hydrophobic Grid Membrane Filters (HGMF) method to the standard HPB method. Two Federal Laboratories also compared the enzyme linked antibody (ELA)/HGMF method (which is a further development of the EF-18 agar/HGMF method) to the standard method. During this study the false-negative rates ranged from 0% to 15% for the standard HPB method, from 5.88% to 43.5% for the EF-18 agar/HGMF method, and from 0% to 10.5% for the ELA/HGMF method. The EF-18 agar/HGMF method did not compare well with the standard HPB method due to the number of false-negatives. Problems with this method resulted from the inability to isolate colonies of Salmonella on the HGMF due to the small colony size, abnormal colony coloration, and overgrowth by competitors. The ELA/HGMF method, however, was shown to be comparable to the standard HPB method. The main advantages of this method are that the antibody-staining step is independent of colony coloration and carbohydrate utilization on the plating media; the ability to detect some unusual strains of Salmonella irrespective of their atypical reactions on the media; and the ELA staining can indicate the presence of Salmonella even when the HGMF is overgrown by competitors. Also, cultural confirmation can proceed simultaneously yet independently of the ELA staining procedure. The data presented here indicate that this method is worth further study.

Bacteriological Techniques↗
PubMed1992

Review of the American College of Radiology--National Electrical Manufacturers' Association standards activity.

The American College of Radiology and the National Electrical Manufacturers' Association published the ACR-NEMA Digital Imaging and Communications Standard in 1985. Implementations are just now becoming available. During this time, working groups of the committee responsible for the standard have been very active. An expanded version of the standard was published in 1988 and a third version, to be known as Digital Imaging and Communications in Medicine (DICOM), is being prepared for publication in 1992. This paper briefly reviews the history of the standard, describes recent activities, outlines the extensions planned for the DICOM standard, and describes the participation of the committee in international radiological imaging standards activities.

Diagnostic Imaging↗
PubMed1994

Safety-critical software and current standards initiatives.

This paper sets out to examine the role of standards in the development of safety-critical software. It starts with a brief discussion on the nature and role of standards and then moves on to identify some of the standards making bodies. Safety-critical software is next discussed and the problems of software safety are contrasted with those of traditional electromechanical devices. There then follows a review of some of the current initiatives to produce standards addressing the development of safety-critical systems containing software. Two standards are then examined in detail to provide an insight into what requirements are placed on the developers of safety-critical software. Lastly, mention is made of some weaknesses that are inherent in today's standards, and some of the efforts that are being made to address these problems are discussed.

Accidents, Occupational↗
PubMed1991

Standard setting processes and regulations for environmental contaminants in drinking water: state versus federal needs and viewpoints.

The primary objective of a standard setting process is to arrive at a drinking water concentration at which exposure to a contaminant would result in no known or potential adverse health effect on human health. The drinking water standards also serve as guidelines to prevent pollution of water sources and may be applicable in some cases as regulatory remediation levels. The risk assessment methods along with various decision making parameters are used to establish drinking water standards. For carcinogens classified in Groups A and B by the United States Environmental Protection Agency (USEPA) the standards are set by using nonthreshold cancer risk models. The linearized multistage model is commonly used for computation of potency factors for carcinogenic contaminants. The acceptable excess risk level may vary from 10(-6) to 10(-4). For noncarcinogens, a threshold model approach based on application of an uncertainty factor is used to arrive at a reference dose (RfD). The RfD approach may also be used for carcinogens classified in Group C by the USEPA. The RfD approach with an additional uncertainty factory of 10 for carcinogenicity has been applied in the formulation of risk assessment for Group C carcinogens. The assumptions commonly used in arriving at drinking water standards are human life expectancy, 70 years; average human body weight, 70 kg; human daily drinking water consumption, 2 liters; and contribution of exposure to the contaminant from drinking water (expressed as a part of the total environmental exposure), 20%. Currently, there are over 80 USEPA existing or proposed primary standards for organic and inorganic contaminants in drinking water. Some of the state versus federal needs and viewpoints are discussed.

Carcinogens, Environmental↗
PubMed1984

Company doctors: standards of care and legitimacy: a case study from Canada.

Company doctors have been criticized for poor standards of care and bias towards their employers interests. This paper reports on interviews with 24 company doctors in the province of Ontario, Canada. It uses company doctors' accounts of their work and careers to highlight aspects of corporate medicine which may help to produce questionable standards of care and present obstacles to doctors' attempts to increase their legitimacy. Apparent variations in the quality of care in contract practice and full-time employment in a company are discussed and it is suggested that greater attention may need to be devoted to improving the standards of care in smaller companies. Patterns of recruitment, doctors' beliefs about the changing nature of occupational medicine, as well as contradictory definitions of the proper sphere of occupational medicine may also have an effect on standards of care and the degree of legitimacy accorded to company doctors. The responses of doctors to charges of bias are discussed and it is suggested that they may neglect the major reason for such charges--that they are employed by companies and are thereby constrained to favour their employers' interests. The paper proposes the need for further research on standards of occupational medical care, whether these vary with respect to context of practice and whether there are appreciable differences in standards of practice among doctors employed by companies, unions, universities and government. Modest proposals for future health policy are also indicated.

Humans↗
PubMed1995

Comparison of exertion required to perform standard and active compression-decompression cardiopulmonary resuscitation.

OBJECTIVE: Active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) utilizes a hand-held suction device with a pressure gauge that enables the operator to compress as well as actively decompress the chest. This new CPR method improves hemodynamic and ventilatory parameters when compared with standard CPR. ACD-CPR is easy to perform but may be more labor intensive. The purpose of this study was to quantify and compare the work required to perform ACD and standard CPR. METHODS: Cardiopulmonary testing was performed on six basic cardiac life support- and ACD-trained St. Paul, MN fire-fighter personnel during performance of 10 min each of ACD and standard CPR on a mannequin equipped with a compression gauge. The order of CPR techniques was determined randomly with > 1 h between each study. Each CPR method was performed at 80 compressions/min (timed with a metronome), to a depth of 1.5-2 inches, and with a 50% duty cycle. RESULTS: Baseline cardiopulmonary measurements were similar at rest prior to performance of both CPR methods. During standard and ACD-CPR, respectively, rate-pressure product was 18.2 +/- 3.0 vs. 23.8 +/- 1.7 (x 1000, P < 0.01); mean oxygen consumption 15.98 +/- 2.29 vs. 20.07 +/- 2.10 ml/kg/min or 4.6 +/- 0.7 vs. 5.7 +/- 0.6 METS (P < 0.01); carbon dioxide production 1115.7 +/- 110 vs. 1459.1 +/- 176 ml/min; respiratory exchange ratio 0.88 +/- 0.04 vs. 0.92 +/- 0.04 (P = NS); and minute ventilation 35.5 +/- 5.1 vs. 45.6 +/- 9.2 l/min (P < 0.01). CONCLUSIONS: Approximately 25% more work is required to perform ACD-CPR compared with standard CPR. Both methods require subanaerobic energy expenditure and can therefore be sustained for a sufficient length of time by most individuals to optimize resuscitation efforts. Due to the slightly higher work requirement, ACD-CPR may be more difficult to perform compared with standard CPR for long periods of time, particularly by individuals unaccustomed to the workload requirement of CPR, in general.

Adult↗
PubMed1977

Biological and immunological characterization of human luteinizing hormone: II. A comparison of the immunological and biological activities of pituitary extracts after electrofocusing using different standard preparations.

The profile of immunologically active human luteinizing hormone (hLH) was determined in aqueous pituitary extracts after electrofocusing using two radioimmunoassay systems and the estimates for each fraction were compared to those obtained by an in vitro bioassay method. Similar biological and immunological profiles were obtained in the pH 7.0-9.0 region, where most of the biological activity was present. Biological to immunological (B/I) ratios ranging from 0.6 to 1.7 (mean ratio 1.01; n = 21) were found in the major biologically active fractions of this pH region when a highly purified human pituitary LH preparation (68/40) was used as standard in both types of assays. The close proximity of these ratios to unity indicates a similar composition of biological and immunological activities in all these fractions in relation to that of the highly purified standard. However, marked discrepancies were observed in the pH region 3.0-7.0 where the B/I ratios ranged from 0.1 to 0.9, indicating the presence of immunological activity associated with relatively little biological activity. When impure human LH preparations of pituitary (69/104) and urinary (hMG 2nd IRP) origin were used as standards for the bioassay and radioimmunoassay of the hLH present in the major fractions of the pH region 7.0-9.0, significantly higher B/I ratios were obtained than with the use of the highly purified standard (68/40). These elevated B/I ratios are attributed to the presence in the impure standard preparations of immunological activity, which is associated with little or no biological activity. These observations may provide an explanation for the differences in B/I ratios which were reported for hLH in plasma, using different standard preparations.

Biological Assay↗