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At least 127 records · Page 7Linked to original sources
PubMed1997

The standard of care is not so standard.

Malpractice lawsuits affect most physicians at some point in their career. Proving that malpractice has been committed is based on substantiation of a variety of elements, including that the patient was rendered care that was "below the standard" of care. While many physicians believe that the "standard" will be judged objectively on the basis of published scientific sources and accepted conventions, the standard is established rather by the testimony of expert witness(es). It is the expert testimony that sets the standard and is proof of the standard. The testimony is open for acceptance or rejection by the judge or jury for a variety of nonscientific reasons. We review what the defendant doctor might expect regarding proof required to establish breach of the standard of care and what the prudent expert should be obliged to demonstrate.

Health Services↗
PubMed1996

Validity of simple approach to scoring and standard setting for standardized-patient cases in an examination of clinical competence.

The results are disappointing, providing little support for the validity of the case-passing decisions based on this simple approach to scoring and standard setting. The case-passing decisions predicted what the case author intended for about only 73% or 74% of the students on average and, with agreement expected by chance removed, predicted what the case author intended for about only 25% of the students. Even with the use of the optimal pass/fail cutoffs and the dropping of students with ambiguous borderline global ratings, the case-passing decisions failed to agree with the case authors' global ratings for 15% to 30% of the students. The findings might be dismissed as simply due to low reliabilities of passing decisions and global ratings based on a single case. Although this concern would apply to intercase reliabilities, which would be subject to case specificity, the appropriate reliabilities here would seem to be intracase (i.e., intrarater), which should be fairly high (if they could be computed). Nevertheless, it seems reasonable to expect much better agreement between results of case scoring and of standard setting developed by the case author and the case author's global ratings of performance on that case, given that the case author might recall the checklist, assign a weight to each item, and so forth. Also, case-passing decisions would possibly agree more with global ratings of live or videotaped performances than with ratings of written summaries of performance; however, that question remains a challenge for further research. In conclusion, the study provides only weak evidence, at best, for the validity of the scoring and standard setting commonly used with SP assessment. The results do not undermine claims about the realism of the SP approach, however, nor do they call into question the standardization afforded by this method of assessing clinical competence. The results do raise serious concerns about this simple approach to scoring and standard setting for SP-based assessments and suggest that we should focus more on the observation and evaluation of actual student performance on SP cases in the development of valid scoring and standard setting.

Achievement↗
PubMedDate not supplied

Nursing standards of patient care and standards of nursing practice--a practical approach.

With the revision of the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) nursing standards in 1991, a new emphasis has been placed on the nursing standards of patient care and the standards of nursing practice (Claflin, 1990). These standards provide the basis for nursing care and the foundation for nursing's contributions to an interdisciplinary quality improvement program. This article will describe how nursing standards of patient care and standards of nursing practice have been developed and integrated into a nursing department's documentation plan and quality improvement program.

Accreditation↗
PubMed1981

Self-selection of standards by children: The relative effectiveness of pupil-selected and teacher-selected standards of performance.

This study examines the effects of contingent reinforcement under conditions of pupil-selected and teacher-selected performance standards upon pupils' academic response rates. The academic response rate was measured by the number of correct responses emitted per session. Thirty pupils (15 second-graders and 15 third-graders) were randomly assigned to one of three experimental groups, based on matched triplets. One group worked under pupil-selected standards; the second group worked under standards selected by the experimenter with each pupil yoked to a member of the pupil-selected standards groups. Both groups participated in the calculation of their daily earnings. The third group served as a no-contingency control group. Baseline academic response rates on writing and math tasks were determined. During the experimental sessions reinforcement was provided in the form of points which were later traded for tangible rewards. The pupil-selected standards group showed a significantly greater number of correct responses in the writing and math tasks than the externally selected standards group.

Journal Article↗
PubMed2003

[Standardization of cancer treatment and legal medical standards].

Legal medical standards are usually applied in two ways in Japanese medical malpractice cases. One application is a judgment on the quality of medical treatment, and the other is an evaluation of the validity of informed consent. Legal medical standards are not equivalent in all medical institutions. If physicians in a medical institution are expected to be aware of the most recent medical knowledge, that becomes the medical standard of the institution. For physicians in major metropolitan medical institutions, such knowledge constitutes the medical standard even before it is published in the guidelines of a committee of an established national medicoprofessional society. The standardization of cancer treatment may be used as evidence in medical malpractice suits brought by cancer patients based on both the quality of treatment and valid informed consent. In addition, it is possible that the validity of informed consent may be given more weight by the courts than the following of a course of standardized treatment by individual physicians/medical institutions in cases where patients have done extensive research on and exhibit informed knowledge of new treatment modalities.

Humans↗
PubMed1997

[Improvement of inter-assay for the standardization of PT and TT--clinical significance of local standardization method].

We performed a nationwide Inter-assay including 112 laboratories for the standardization of prothrombin time (PT) and thrombotest (TT). The data were expressed as seconds, percentile and INR. INR was expressed by 2 methods; Method I (conventional method): INR was expressed using each ISI assigned for reagent or reagent-instrument at the respective laboratories and Method II (local standardization method): INR was expressed using each reference curve created with INR assigned standard plasmas at the respective laboratories. (1) Sample distribution of PT as well as TT was the smallest with the data expressed by Method II followed by Method I and then by percentile. The data expressed by seconds was widely distributed and not useful for the standardization of PT and TT. (2) Even the sample distribution obtained by Method II was dependent on the different ISI of the reagents, as it was found that the larger the ISI of the reagents, the wider the distribution of data. (3) The difference between PT and TT of each test plasma was analysed by t-test. It was found that the difference was insignificant when both data were expressed by Method II, but significant when expressed by Method I, suggesting that PT and TT were interchangeable with the use of Method II. (4) Sample distribution of percentile expression and INR with the use of method II was compared. It was revealed that the sample distribution of INR was smaller than that of percentile. It was concluded that INR expressed by the local standardization method was most useful for the standardization of PT and TT.

Humans↗
PubMed2005

Standard reference material 2036 near-infrared reflection wavelength standard.

Standard Reference Material 2036 (SRM 2036) is a certified transfer standard intended for the verification and calibration of the wavelength/wavenumber scale of near-infrared (NIR) spectrometers operating in diffuse or trans-reflectance mode. SRM 2036 Near-Infrared Wavelength/Wavenumber Reflection Standard is a combination of a rare earth oxide glass of a composition similar to that of SRM 2035 Near-Infrared Transmission Wavelength/Wavenumber Standard and SRM 2065 Ultraviolet-Visible-Near-Infrared Transmission Wavelength/Wavenumber Standard, but is in physical contact with a piece of sintered poly(tetrafluoroethylene) (PTFE). The combination of glass contacted with a nearly ideal diffusely reflecting backing provides reflection-absorption bands that range from 15% R to 40% R. SRM 2036 is certified for the 10% band fraction air wavelength centroid location, (10%)B, of seven bands spanning the spectral region from 975 nm to 1946 nm. It is also certified for the vacuum wavenumber (10%)B of the same seven bands in the spectral region from 10 300 cm(-1) to 5130 cm(-1) at 8 cm(-1) resolution. Informational values are provided for the locations of thirteen additional bands from 334 nm to 804 nm.

Fiber Optic Technology↗
PubMed1996

Preparation and standardization of U.S. Standard Pertussis Vaccine, Lot No. 11.

The Center for Biologics Evaluation and Research within the U.S. Food and Drug Administration has prepared a new U.S. Standard Pertussis Vaccine. Whole cell pertussis vaccine concentrate was diluted in 5% (w/v) lactose and lyophilized. The preparation was tested for toxicity, sterility, heterogeneity and residual moisture. Based on data from an international collaborative study involving 11 laboratories, the potency was estimated in relation to the U.S. Master Standard Pertussis Vaccine, Lot 4 and the International Standard for Pertussis Vaccine, Lot 2. The potency of the preparation was defined to be 90 units per ampoule. When reconstituted and stored according to instructions, no significant change in potency was observed in the 14 days following reconstitution. This material was shown to be suitable for a pertussis vaccine standard and accordingly it was designated as U.S. Standard Pertussis Vaccine, Lot 11 on March 22, 1994.

Animals↗
PubMed1996

Development and standardization of solid phase assays for the detection of anti-neutrophil cytoplasmic antibodies (ANCA). A report on the second phase of an international cooperative study on the standardization of ANCA assays.

Anti-neutrophil cytoplasmic antibodies (ANCA) are diagnostic markers for systemic vasculitis. They are classically detected by an indirect immunofluorescence test using normal donor neutrophils as substrate. This assay lacks antigenic specificity and is not quantitative. The 'EC/BCR Project for ANCA Assay Standardization' is an international collaboration study with the aim to develop and standardize solid phase assays for ANCA detection. In this part of the study the isolation and characterization of proteinase-3 and myeloperoxidase, the two main target molecules for ANCA, and the development and standardization of ELISAs with these antigens are described. Six laboratories successfully isolated purified proteinase-3 preparations that could be used. Three of these preparations, together with one myeloperoxidase preparation, were subsequently used for ANCA testing by ELISA. The ELISA technique was standardized in two rounds of testing in the 14 participating laboratories. The coefficient of variation of these new assays decreased from values of approx. 50% in the first round to approx. 20% in the second round. We conclude that purified proteinase-3 and myeloperoxidase can be used in standardized ELISAs for ANCA detection. Whether such procedures offer advantages over the IIF test will be determined in a prospective clinical study.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2005

Long-term stability of pure standards and stock standard solutions for the determination of pesticide residues using gas chromatography.

The regular replacement of pure standards used in pesticide residue analysis laboratories and frequent preparation of stock standard solutions, both required by many accreditation bodies, impose considerable demands on a laboratory's resources. In this study, pure standards for all but one (heptenophos) of 118 different pesticides amenable to analysis by GC, and stock standard solutions (1000 microg/ml) prepared from these in toluene, acetone or ethyl acetate have been shown to be stable at < or = -20 degrees C over long periods: 4-13 and 2-8 years, respectively, for pure standards and solutions. Suitable solvents, containers and handling procedures are essential to avoid evaporation from solutions.

Chromatography, Gas↗
PubMed2005

Biological standardization of human interferon beta: establishment of a replacement world health organization international biological standard for human glycosylated interferon beta.

Human interferon beta (IFN-beta) has been developed as a major biotherapeutic agent for the treatment of multiple sclerosis. Since World Health Organization (WHO) international standards (IS) for IFN-beta were established several years prior to the development of clinical grade IFN-beta products, a number of scientific issues with regard to the biological standardisation of natural and recombinant IFN-beta products have emerged. In order to address these issues, an international collaborative study to evaluate WHO IS and candidate international standards (CIS) of IFN-beta was instigated by the National Institute for Biological Standards and Control (NIBSC) in 2000 and was carried out in the succeeding year. Sixteen expert laboratories from 8 countries worldwide participated in the study. They performed titrations on 8 different IFN-beta preparations, including IS and new CIS, in a variety of mainly antiviral- but also including some antiproliferative- and reporter gene-assays, and contributed raw data from these assays to NIBSC for statistical analysis and calculation of potencies. While both intra- and inter-laboratory variation of potency estimates was evident, overall validity of the study as a whole was clearly shown by comparison of two pairs of internal coded duplicates, which gave the expected relative potency of 1 and the lowest inter-laboratory variability of potency estimates in all assay types. The CIS containing Chinese hamster ovary (CHO) cell- or human fibroblast-derived, glycosylated, IFN-beta gave similar low inter-laboratory variation in potency estimates one to another as the coded duplicates, which was significantly less than to the 2nd WHO IS of IFN-beta, human fibroblast-derived, Gb23-902-531. One of these CIS, designated 00/572, containing CHO cell-derived IFN-beta and formulated with both bovine casein and human serum albumin, could be assigned a potency, consistent for all assay types, of 40,000 international units (IU) per ampoule relative to the IU of the 2nd IS of IFN-beta, Gb23-902-531. Other CIS containing glycosylated IFN-beta, either CHO cell- or human-fibroblast-derived, could also be assigned potency values that were continuous with the IU of Gb23-902-531 and 00/572. However, greater inter-laboratory variations in estimates were evident from comparisons of Gb23-902-531 or 00/572 with either the 1st IS for E. coli-derived, non-glycosylated, IFN-beta with serine substitution at position 17 (IFN-beta Ser 17 mutein), Gxb02-901-535, or with a CIS (00/574) containing IFN-beta Ser 17 mutein. Indeed, variations in potency estimates for preparations containing IFN-beta Ser 17 mutein were sufficiently large to indicate that assays could distinguish preparations of IFN-beta Ser 17 mutein from preparations of glycosylated IFN-beta. Thus, neither the 2nd IS of IFN-beta, Gb23-902-531, containing fibroblast-derived IFN-beta, nor CIS, 00/572, containing CHO cell-derived IFN-beta, was appropriate for standardisation of preparations of IFN-beta Ser 17 mutein. Conversely, neither the IS of IFN-beta Ser 17 mutein, Gxb02-901-535, or a CIS of IFN-beta Ser 17 mutein, 00/574, was appropriate for the standardisation of preparations of glycosylated IFN-beta. CIS 00/572, containing CHO cell-derived, glycosylated IFN-beta, was clearly shown to be suitable to serve as a primary standard for glycosylated forms of IFN-beta, especially clinical grade IFN-beta-1a products. It was further shown to exhibit high thermal and long-term stability. Since the CHO cell-derived IFN-beta used for preparation of 00/572 was of a greater purity than the IFN-beta used for the 2nd IS of IFN-beta, Gb23-902-531, it was recommended by the WHO Informal Consultation on the Standardisation of Cytokines, Growth Factors and Other Endocrinological Substances, which met in October 2003, that 00/572 should replace Gb23-902-531 as the IS for glycosylated IFN-beta. This recommendation was accepted by the WHO Expert Committee on Biological Standardization (ECBS) at its annual meeting in November 2003 and 00/572 was established as the 3rd IS for human glycosylated IFN-beta with an assigned potency of 40,000 IU. As this study identified no advantage to replacing the existing 1st IS for IFN-beta Ser 17 mutein, Gxb02-901-535, WHO ECBS accepted that this should continue to serve as the IS for this material.

Animals↗
PubMed2002

The Universal Standard Scale: proposed improvements to the American National Standards Institute (ANSI) scale for corneal topography.

PURPOSE: To evaluate the American National Standards Institute (ANSI) corneal topography scale (ANSI Z-80.23-1999) and to develop a Universal Standard Scale (USS) based on scientific principles and clinical usefulness. DESIGN: Retrospective data analysis and computer modeling of frequency of corneal power distributions. METHODS: Four variations of corneal topography color scales were constructed using the ANSI standard description. The scales used 21 contour intervals with step sizes of 0.5, 1.0, or 1.5 diopters (D). In example 1, hue was varied, whereas saturation and brightness were held constant. In example 2, hue was varied systematically, whereas luminance was varied to compensate for spectral sensitivity. In example 3, hue was varied, whereas luminance was adjusted to improve color contrast at the center of the scale. In example 4, the palette was generated by varying the red, green, and blue color intensity levels. In the USS, colors were defined by hue, brightness, and saturation, and appearance was optimized by using contrast. The contour interval was determined from the standard deviation of keratometry for 27 normal corneas. The scale range was based on corneal powers found in 388 topography maps of 12 different corneal conditions. RESULTS: ANSI-derived maps were difficult to interpret because of poor color contrast and the inability to associate contours with specific colors in the scale. The 0.5 D interval slightly improved the appearance of some patterns but reduced the useful clinical range of the scale. ANSI colors did not match the user's expectations; abnormal patterns appeared in shades of green, which is associated with normality. The standard deviation of keratometry readings for the normal population was 1.59 D. Hence, the contour interval for the USS was set to 1.5 D. More than 99.9% of the corneal powers in 388 clinical maps were within the range of 30 to 67.5 D, which was chosen as the range for the USS. CONCLUSIONS: The ANSI scale for corneal topography is a series of scales that lead to clinical misinterpretations. The alternative USS would provide uniform presentation, unambiguous interpretation, and greater ease of comparison among maps produced by different topographers.

Color↗
PubMedDate not supplied

Symposium on Metrology and Standards for Cell Signaling: Impact on Tissue Engineering, National Institute for Standards and Technology, October 14-15, 2003.

The Symposium on Metrology and Standards for Cell Signaling: Impact on Tissue Engineering, was cosponsored by the National Institute for Standards and Technology (NIST) and ASTM International, and was held at the NIST on October 14 and 15, 2003. The purpose of the symposium was to discuss the role of standards and quantitative measurements of cellular responses for the field of tissue engineering. Accurate and quantitative measurements, reference materials, and standards are needed to facilitate the understanding and control of cell responses to materials, culture media, and the in vivo environment. Speakers included government researchers from the NIST, the Food and Drug Administration, and the National Cancer Institute; vice presidents, chief executive officers, and directors of research from companies; and academic researchers in engineering, medicine, and cell biology. The metrology needs identified include quantitative assays of cell signaling pathways, bioinformatics that will allow consolidation of these complex data and permit correlative parameters to be identified, well-characterized standardized cell lines against which responses in other cells can be compared, and reference materials for use in control experiments.

Cell Culture Techniques↗