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PubMed1992

Rabies vaccine standardization: International Collaborative Study for the Characterization of the fifth International Standard for Rabies Vaccine.

A collaborative study was carried out to establish a replacement for the International Standard for Rabies Vaccine, the stocks of which are exhausted. Three rabies vaccines for human use derived from different rabies virus strains and prepared on different cell culture substrates were compared with the International Standard for Rabies Vaccine using in vivo and in vitro assay methods in a collaborative study involving 14 participants. The proposed fifth International Standard (PISRAV) which was derived from the same virus strain as the present international standard preparation, the Pitman Moore (PM) strain, was found to be approximately twice as potent relative to the International Standard in immunogenicity assays as in antigenicity assays. On the other hand another vaccine, derived from the LEP strain, was considerably more potent in antigenicity assays than in immunogenicity assays. The glycoprotein of the proposed replacement standard measured in antigenicity assays appeared to be stable at +37 degrees C for 245 days, whereas the immunogenicity of the proposed replacement vaccine was sensitive to this heat treatment and the vaccine lost 66% of its immunogenic potency. The results of this study indicate that the NIH protection test should continue to form the primary basis for potency assay of rabies vaccine as glycoprotein content does not appear to correlate with immunogenic potency for different types of vaccine. The vaccine coded PISRAV has been established as the fifth International Standard for Rabies Vaccine and a potency of 16 International Units of Rabies Vaccine (based on the immunogenicity assays) assigned to the contents of each ampoule. Each ampoule has also been assigned a unitage of 10 IU of PM Rabies Virus Glycoprotein and 135 IU of PM Rabies Virus Ribonucleoprotein.

Animals↗
PubMed2003

Setting defensible performance standards on OSCEs and standardized patient examinations.

Recently, standardized patient assessments and objective structured clinical examinations have been used for high-stakes certification and licensure decisions. In these testing situations, it is important that the assessments are standardized, the scores are accurate and reliable, and the resulting decisions regarding competence ar equitable and defensible. For the decisions to be valid, justifiable standards, or cut-scores, must beset. Unfortunately, unlike the body of research specifically dedicated to multiple-choice examinations, relatively little research has been conducted on standard-setting methods appropriate for use with performance-based assessments. The purpose of this article is to provide the reader with some guidance on how to set defensible standards on performance assessments, especially those that utilize standardized patients in simulated medical encounters. Various methods are discussed and contrasted, highlighting the relevant strengths and weaknesses. In addition, based on the prevailing literature and research, ideas for future studies and potential augmentations to current performance-based standard setting protocols are advanced.

Certification↗
PubMed2005

Japanese standard reference material for JDS Lot 2 haemoglobin A1c. I: Comparison of Japan Diabetes Society-assigned values to those obtained by the Japanese and USA domestic standardization programmes and by the International Federation of Clinical Chemistry reference laboratories.

BACKGROUND: The Committee on Standardization of Laboratory Testing Related to Diabetes Mellitus of the Japan Diabetes Society (JDS) previously recommended use of the primary calibrator (JDS Lot 1) prepared by the former Committee for Standardization of Glycohemoglobin for standardizing the measurement of haemoglobin A1c (HbA1c). Owing to the depletion of vials of Lot 1 in March 2001, the present committee certified a new reference material, Lot 2, now distributed by the Health Care Technology Foundation (HECTEF). The standardization programme for HbA1c measurement in Japan is currently based on Lot 2, which has values assigned from within Lot 1; the Lot 1 values were consensus values based on assays by laboratories in the Japanese national quality control programme. In this study, for the purpose of international comparison and standardization, Lot 2 was assayed by the JDS reference laboratories, the National Glycoprotein Standardization Program (NGSP) in the USA, and by reference laboratories approved by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). METHOD: The HbA1c values of JDS Lot 2 were transferred from those assigned to Lot 1 using KO500, a high-resolution HPLC method, at three laboratories approved by the JDS committee. Subsequently, vials of JDS Lot 2 were shipped to and assayed by the NGSP in the USA and 10 IFCC reference laboratories. RESULT: The JDS-assigned HbA1c values (from Lot 1) are 4.04 for Level 1, 5.38 for Level 2, 7.32 for Level 3, 9.88 for Level 4, and 12.63 for Level 5, all expressed as a percentage of total haemoglobin. The values obtained by NGSP and the IFCC laboratories gave the following formulas: NGSP value(%)=JDS value(%)+0.3%; IFCC value(%)=1.068xJDS value(%)-1.741%. CONCLUSION: Although the values obtained by the IFCC laboratories are significantly lower than the values assigned to Lot 2 by the JDS, the relationship is linear. In addition, standardization of HbA1c based on JDS Lot 2 is currently at a satisfactory level in Japan. As a result, the reassignment of values for Lot 2 to agree with the IFCC values should be relatively easy and will be done after all relevant parties agree to the change.

Blood Chemical Analysis↗
PubMed2003

Estimate of standard deviation for a log-transformed variable using arithmetic means and standard deviations.

Analyses of study variables are frequently based on log transformations. To calculate the power for detecting the between-treatment difference in the log scale, we need an estimate of the standard deviation of the log-transformed variable. However, in many situations a literature search only provides the arithmetic means and the corresponding standard deviations. Without individual log-transformed data to directly calculate the sample standard deviation, we need alternative methods to estimate it. This paper presents methods for estimating and constructing confidence intervals for the standard deviation of a log-transformed variable given the mean and standard deviation of the untransformed variable. It also presents methods for estimating the standard deviation of change from baseline in the log scale given the means and standard deviations of the untransformed baseline value, on-treatment value and change from baseline. Simulations and examples are provided to assess the performance of these estimates.

Confidence Intervals↗
PubMed1995

Ergonomics and international standards: introduction, brief review of standards for anthropometry and control room design and useful information.

The International Organization for Standardization (ISO) coordinates the production of internationally accepted standards, and involves over 100 countries. ISO TC 159 'Ergonomics' was set up in 1975. In 1988, the Comite Europeen De Nomalisation (CEN) established CEN TC 122 'Ergonomics' for the production of European standards. An exhaustive list of standards, proposed standards and work items is provided. Standards in the areas of anthropometry and control room design are presented. Additional useful information is provided in the form of abbreviations and terms and a list of addresses of where to obtain standards.

Journal Article↗
PubMed1974

Gene differences between the sex ratio and standard gene arrangements of the X chromosome and linkage disequilibrium between loci in the standard gene Drosophila pseudoobscura.

The Standard and Sex Ratio gene arrangements of the X chromosome of D. pseudobscura differ from each other in allele frequencies at the four X chromosome loci, esterase-5, adult acid phosphatase-6, phosphoglucomutase-1 and octanol dehydrogenase-3. The Standard arrangement which is the common arrangement in all populations is polymorphic at these loci in varying degrees, the geographically less widespread Sex Ratio arrangement has little polymorphism and is genically predominantly E-5(1.04) AP-6(-) Pgm1(1.0) ODH-3(1.0). The Sex Ratio arrangement from different populations is alike at all of the four loci, the Standard arrangement shows some gene frequency differences among populations. The Standard and Sex Ratio arrangements differ from each other by three inversions which suggests that the two arrangements are "old". Gene differences between these two chromosome arrangements can be explained due to differential natural selection of alleles in the Standard and Sex Ratio arrangments.-The order and percent recombination among these four loci in the Standard arrangement are: E-5-.294-AP-6-.335-Pgm-1-.024-ODH-3. The Standard X chromosomes from four different wild populations were analyzed for evidence of linkage disequilibrium between pairs of loci at these four loci. No evidence of linkage disequilibrium between pairs of loci was obtained. However, when linkages involving simultaneously three loci, E-5, AP-6 and Pgm-1 are considered, then significant departure from linkage equilibrium is observed.

Acid Phosphatase↗
PubMed2004

Standardized RT-PCR and the standardized expression measurement center.

Standardized reverse transcriptase polymerase chain reaction (StaRT-PCR) is a modification of the competitive template (CT) RT method described by Gilliland et al. StaRT-PCR allows rapid, reproducible, standardized, quantitative measurement of data for many genes simultaneously. An internal standard CT is prepared for each gene, cloned to generate enough for 10(9) assays and CTs for up to 1,000 genes are mixed together. Each target gene is normalized to a reference gene to control for cDNA loaded in a standardized mixture of internal standards (SMIS) into the reaction. Each target gene and reference gene is measured relative to its respective internal standard within the SMIS. Because each target gene and reference gene is simultaneously measured relative to a known number of internal standard molecules in the SMIS, it is possible to report each gene expression measurement as a numerical value in units of target gene cDNA molecules/ 10(6) reference gene cDNA molecules. Calculation of data in this format allows for entry into a common databank, direct interexperimental comparison, and combination of values into interactive gene expression indices.

DNA, Complementary↗
PubMed1991

[Contact eczema and "standard test"--do "International Standard Test Series" coincide with Austrian local characteristics?].

Testing with a "standard" group of substances has proved of great value when allergic contact dermatitis is suspected and the offending agent cannot be pinpointed by careful history-taking. But internationally standardized series do not take into account locally important and individual factors, changing consumer habits or economic aspects. We have, thus, compared the suitability of two standard series, the ICDRG-European and the DKG-German standard, for Austrian purposes. 1,478 patients with a clinical diagnosis of contact dermatitis were patch tested between 11/88 and 4/90 with the ICDRG allergens; the second collective of 505 patients was tested between 5/90 and 1/91 with the DKG series. Only 12 out of the 27 substances of the ICDRG series exceeded the critical incidence of 1%; 6 were below this limit but positive in more than 0.5% and 9 hardly ever aroused positive reactions. In the DKG series, 17 out of 23 substances surpassed the limit, 2 were positive in more than 0.5%, and 4 caused virtually no reactions. However, 4 allergens with frequent sensitization rates were included neither in the ICDRG nor in the DKG series and 2 others were missing in the over-dimensioned ICDRG standard. Our results demonstrate that internationally established standard series have to adapted for the local situation in Austria, and that a constant review is essential with replacement of allergens as necessary according to changing production techniques and consumer habits. Suggestions for an "Austrian standard patch test series" are proposed on the basis of our results but in spite of being helpful in general terms interpretation of such a test in the individual patient with eczema remains problematic.

Allergens↗
PubMed1970

Replacement of the international standard for tetanus antitoxin and the use of the standard in the flocculation test.

Since 1935 the International Unit for Tetanus Antitoxin has been defined as the activity contained in a certain weight of the first International Standard for Tetanus Antitoxin. As stocks of this standard had become depleted, 11 laboratories in 8 countries were requested to participate in a collaborative assay of a preparation proposed as a replacement.The assay results were analysed and presented to the WHO Expert Committee on Biological Standardization in 1969 which established the preparation studied as the second International Standard for Tetanus Antitoxin and defined the International Unit for Tetanus Antitoxin as the activity contained in 0.03384 mg of the second International Standard for Tetanus Antitoxin. This definition would ensure the continuity of the size of this international unit.The analysis of the collaborative studies also showed that the second International Standard for Tetanus Antitoxin has suitable properties for use in the flocculation test for the determination of the antigen content of tetanus toxoids in Lf values. The designation Lf-equivalent is described and the problems relating to the use of this term for the expression of results of in vitro assays are analysed in relation to the use of international units for expressing results of in vivo assays. As the second International Standard for Tetanus Antitoxin has an in vivo/in vitro ratio of 1.4, the Lf-equivalent of this antitoxin is 1.4 times less than its unitage.

Animals↗
PubMed2004

The Cardiology Audit and Registration Data Standards (CARDS), European data standards for clinical cardiology practice.

AIMS: Systematic registration of data from clinical practice is important for clinical care, local, national and international registries, and audit. Data to be collected for these different purposes should be harmonized. Therefore, during Ireland's Presidency of the European Union (EU) (January to June 2004), the Department of Health and Children worked with the European Society of Cardiology, the Irish Cardiac Society, and the European Commission to develop data standards for clinical cardiology. The Cardiology Audit and Registration Data Standards (CARDS) Project aimed to agree standards for three modules of cardiovascular health information systems: acute coronary syndromes (ACS), percutaneous coronary interventions (PCI), and clinical electrophysiology (pacemakers, implantable cardioverter defibrillators, and ablation procedures). METHODS AND RESULTS: Data items from existing registries and surveys were reviewed to derive draft data standards (variables, coding, and definitions). Variables common to the three modules include demographics, risk factors, medication, and discharge and follow-up data. Modules about a procedure contain variables on the lesion, the device, and medication during the procedure. The ACS module includes presenting symptoms, reperfusion and acute treatments, and procedures in hospital and at follow-up. CONCLUSIONS: The data standards were discussed and adopted at a conference involving EU member states in Cork, Ireland, in May 2004. After a pilot study, the standards will be disseminated to stakeholders throughout Europe.

Cardiology↗
PubMed1999

Risk-related standards of competence: continuing the debate over risk-related standards of competence.

This discussion paper addresses Ian Wilks' defence of the risk-related standard of competence that appears in Bioethics 11. Wilks there argues that the puzzle posed by Mark Wicclair in Bioethics 5 against Dan Brock's argument in favour of a risk-related standard of competence -- namely that Brock's argument allows for situations of asymmetrical competence -- is not a genuine problem for a risk-related standard of competence. To show this, Wilks presents what he believes to be two examples of real situations in which asymmetrical competence arises. I argue that insofar as Wilks equivocates two senses of competence in his examples -- namely, competence to perform a task and competence in performing a task -- Wilks is unable to illustrate the existence of real situations of asymmetrical competence. By examining the way in which Wilks equivocates two senses of competence in his examples, and by applying the results of this examination to the problem of patient competency within the medical field, I argue that not only does Wilks fail to show that situations of asymmetrical competence exist, but he is also unable to provide a foundation for understanding how the risk-related standard of competence can strike a balance between an individual's autonomy and benevolent intervention. I thus conclude that insofar as Wilks fails to answer the objections raised by Wicclair and others against the risk-related standard of competence, the risk-related standard of competence continues to be undermined by the problem of asymmetrical competence.

Altruism↗
PubMed2000

Beta-blocker supplementation of standard drug treatment for schizophrenia.

BACKGROUND: Many people with schizophrenia or similar severe mental disorders do not achieve a satisfactory treatment response with ordinary antipsychotic drug treatment. In these cases, various add-on medications are used, among them beta-adrenergic receptor antagonists (beta-blockers). OBJECTIVES: To evaluate the clinical effectiveness of beta-blockers as an adjunct to antipsychotic medication in schizophrenia or similar severe mental disorders. SEARCH STRATEGY: Publications in all languages were searched from the following databases: Biological Abstracts, CENTRAL of The Cochrane Library, Cochrane Schizophrenia Group's Specialised Register, EMBASE, LILACS, MEDLINE, and PsycLIT. The reference section of papers included were screened. SELECTION CRITERIA: All randomised controlled trials comparing beta-blockers with placebo as an adjunct to conventional antipsychotic medication for those with schizophrenia. DATA COLLECTION AND ANALYSIS: Studies were selected and then data extracted, independently, by at least two reviewers. Odds ratios and 95% confidence intervals of homogeneous dichotomous data were calculated with the Peto method. A random effects model was used for heterogeneous dichotomous data. Weighted mean differences were calculated for continuous data. MAIN RESULTS: Currently the review includes five studies but data are poorly presented and do not evidence any effect of beta-blockers as an adjunct to conventional antipsychotic medication. REVIEWER'S CONCLUSIONS: At present beta-blockers cannot be recommended in the treatment of schizophrenia. Any possible benefit of adjunctive beta-blockers is obscured by the poor reporting of the included studies. Existing data on beta-blockers as adjunctive medication to antipsychotics for those with schizophrenia should be collected and re-analysed in order to allow confident conclusions about the effect of this treatment or the need for further trials.

Adrenergic beta-Antagonists↗