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Side-by-side comparisons are an effective way to compare different GLP standards. These comparisons allow easy elucidation of differences in the regulations. A side-by-side comparison of the EPA, GLPs and the IMAFF GLPs was constructed and evaluated. The major differences are reported.
The use of standardized patients (SPs) is an emerging strategy in palliative care education. We have used this strategy to provide pediatric residents with a structured educational experience focused on effectively communicating bad news and concurrently understanding the emotions that they and the parents may experience. This article describes the importance of and process for realistic SP case development explicitly designed to address predetermined educational goals and objectives. Topics addressed include the types of potential SPs that can be utilized, their potential strengths and weaknesses, training issues which include giving constructive feedback, implementation strategies for the case scenarios and evaluation strategies.
Feinstein's criticism of epidemiology are summarized and evaluated. His major premises appear to be that methodologic errors inevitably result in false positive associations, that epidemiologists are complacent about methodology, and that epidemiologists encourage overinterpretation of epidemiologic data by the public. We challenge these premises and discuss a number of technical errors that underlie Feinstein's writings: he generally ignores the tendency of nondifferential exposure misclassification to dilute associations; he inappropriately interchanges measure of disease occurrence, which leads him to erroneous assertions regarding differences among studies; and he asserts that absence of a dose-response gradient precludes causality, despite the fact that causal effects need not follow a monotonic dose-response curve over the entire range of exposure. We also challenge his assertions that contradictory results necessarily indicate poor study methods and that prior beliefs of the data collectors inevitably affect study results in ways not apparent in the study methods. Feinstein's approach to the use of epidemiology in policy formulation ignores the need to weigh all evidence and distinguish important from unimportant biases. We illustrate this point by documenting how the use of Feinstein's "scientific standards" in evaluating the evidence linking aspirin to Reye's syndrome would have led to costly errors in medical practice.
PURPOSE: To assess the effects of examinee gender, standardized-patient (SP) gender, and, in particular, their interaction on ratings made by SPs of examinees' interpersonal and communication skills in a performance-based examination of clinical competence. METHOD: The examination was administered to four classes of senior medical students (about 70 per class) at Southern Illinois University School of Medicine, 1988-1991. The skill dimensions tested were clarity of communication, thoroughness of explanation, professional manner, personal manner, and overall patient satisfaction. Split-plot analyses of variance were used. RESULTS: There was no interaction of examinee gender and SP gender for any of the five rating scales. There was no main effect of examinee gender for four of the five scales; however, for personal manner, women students were rated slightly higher than men students. There was a main effect of SP gender, but the effect was not consistent from rating scale to rating scale or from class to class. Nevertheless, differences in ratings given by men and women SPs should not be of psychometric concern, since the ratings of men and women examinees are necessarily affected alike. CONCLUSIONS: Except for the women examinee's higher performance in personal manner, the men and women examinees generally performed equally well with respect to interpersonal and communication skills, and they performed equally well regardless of the gender of the SP.
BACKGROUND: In previous studies assessing the effects of student gender, standardized-patient (SP) gender, and their interaction on multiple-station examinations of clinical competence, SP gender was confounded with cases, that is, male SPs were used for some cases and female SPs for others. The authors conducted two studies to investigate the effects of gender on a single case by using a male SP and a female SP for the same case. METHOD: Both studies involved one SP case in a comprehensive clinical evaluation used to assess fourth-year students at the end of a required ambulatory care clerkship at Saint Louis University School of Medicine in 1990-91 and 1991-92. In Study 1, 45 students in four rotations saw the same male SP; 42 students in three other rotations saw the same female SP. In Study 2, 69 students in six rotations were randomly assigned either the male SP (28) or the female SP (41) within the same rotation. For each study, to determine the interaction of student gender and SP gender as well as their main effects, analyses of variance were performed on the students' history-taking and physical examination scores and communication skills ratings. RESULTS: Neither study showed a significant interaction of student gender and SP gender on history taking, physical examinations, or communication skills. CONCLUSION: The findings of both studies suggest that the interaction between student gender and SP gender, unconfounded by case content, had no effect on the students' scores and ratings.
We investigated the effectiveness of prophylactic administration of recombinant activated factor VII (rFVIIa) for cardiopulmonary bypass surgery in children under 1 year old with congenital heart disease (CHD) in a double-blinded, placebo-controlled study. The rFVIIa dose was 40 microg/kg and all patients also received standard haemostatic replacement therapy. The primary endpoint was the time to chest closure from neutralization of heparin with protamine sulphate as this could be most objectively and accurately measured during surgery. Secondary endpoints were volumes of transfused blood, platelet concentrates and fresh-frozen plasma. All adverse events were recorded. In the intention-to-treat analysis there were 76 patients (40 in rFVIIa group and 36 in placebo group). The demographics and severity of CHD were similar in both groups. No benefit of rFVIIa prophylaxis was found in the time to chest closure, which was significantly prolonged in the rFVIIa group (rFVIIa mean +/- SE, 98.8 +/- 27.27 versus 55.3 +/- 29.15, P = 0.0263). In the 41 patients available for a follow-up visit 6 weeks after discharge, the chest closure time was also prolonged in the rFVIIa group (P = 0.0515). There were no significant differences in the secondary endpoints. Adverse events were similar in both groups.
Occurrence-based databases such as the Palaeobiology database (PBDB) provide means of accommodating the heterogeneities of the fossil record when evaluating historical diversity patterns. Although palaeontologists have given ample attention to the effects of taxonomic practice on diversity patterns derived from synoptic databases (those using first and last appearances of taxa), workers have not examined the effects of taxonomic error on occurrence-based diversity studies. Here, we contrast diversity patterns and diversity dynamics between raw data and taxonomically vetted data in the PBDB to evaluate the effects of taxonomic errors. We examine three groups: Palaeozoic gastropods, Jurassic bivalves and Cenozoic bivalves. We contrast genus-level diversity patterns based on: (i) all occurrences assigned to a genus (i.e. both species records and records identifying only the genus), (ii) only occurrences for which a species is identified, and (iii) only occurrences for which a species is identified, but after vetting the genus to which the species is assigned. Extensive generic reassignments elevate origination and extinction rates within Palaeozoic gastropods and origination rates within Cenozoic bivalves. However, vetting increases generic richness markedly only for Cenozoic bivalves, and even then the increase is less than 10%. Moreover, the patterns of standing generic richness are highly similar under all three data treatments. Unless our results are unusual, taxonomic standardization can elevate diversity dynamics in some cases, but it will not greatly change inferred richness over time.
The aim of biological standardization (BS) is to equilibrate the activity (potency) of allergen extracts from different source materials. This was done by performing skin prick tests (SPT) on patients who were sensitive to one of the following 10 allergens: Birch, alder, hazel, timothy, rye grass, velvet grass, cultivated rye, mugwort, D. farinae and Cladosporium herbarum. Patient sensitivity varied within a range of three to four powers of ten for each allergen investigated. The weal size in each patient corresponding to that elicited by histamine 1 mg/ml was calculated using the model log (mean weal diameter) = a + b log (concentration). The correlation coefficients of the regression lines of the allergen dose response relationship were found to be greater than 0.85 in most cases. The median slope for all extracts was 0.24. The slope for Cladosporium was significantly steeper than that for pollens. The amount of material in microgram dry weight (d.w./ml) equal to 1000 biological units/ml (BU/ml) varied within a factor of three between species for all tested purified allergen preparations but Cladosporium. For Cladosporium, about 30 times more material was needed than for D. farinae. When using crude rather than purified material, it was necessary to use five to ten times more to elicit a reaction corresponding to 1000 BU/ml, but the difference was significant only for Cladosporium. The narrow range of allergen concentrations used by us as well as other investigators does not assure positive skin prick test results in all patients with clinical symptoms due to the allergen in question. Skin prick testing should therefore be done over a wide range of concentrations to improve the methods for BS.
Multilaboratory studies were performed to develop MIC quality control limits for the National Committee for Clinical Laboratory Standards reference agar dilution method for anaerobic susceptibility tests. Acceptable MICs were defined as those which include greater than 95% of all 100 MICs generated by the study. Most MIC control limits included either 2- or 3-dilution intervals rather than the more traditional 3-dilution intervals that are described as the mode +/- 1 doubling dilution.
A comparative study of broth macro- and microdilution methods for susceptibility testing of fluconazole, itraconazole, flucytosine, and amphotericin B was conducted with 273 yeasts. The clinical isolates included 100 Candida albicans, 28 Candida tropicalis, 25 Candida parapsilosis, 15 Candida lusitaniae, 15 Candida krusei, 50 Cryptococcus neoformans var. neoformans, 25 Torulopsis (Candida) glabrata, and 15 Trichosporon beigelii strains. Both methods were performed according to the National Committee for Clinical Laboratory Standards' (NCCLS) recommendations (document M27-P). For fluconazole, itraconazole, and flucytosine, the endpoint was the tube that showed 80% growth inhibition compared with the growth control for the macrodilution method and the well with slightly hazy turbidity (score 1) compared with the growth control for the microdilution method. For amphotericin B, the endpoint was the tube and/or well in which there was absence of growth. For the reference macrodilution method, the MICs were determined after 48 h of incubation for Candida spp., T. glabrata, and T. beigelii and after 72 h for C. neoformans var. neoformans. For the microdilution method, either the first-day MICs (24 h for all isolates other than C. neoformans and 48 h for C. neoformans var. neoformans) or the second-day MICs (48 and 72 h, respectively) were evaluated. The agreement within one doubling dilution of the macrodilution reference for all drugs was higher with the second-day MICs than with the first-day MICs for the microdilution test for most of the tested strains. General agreement was 92% for fluconazole, 85.7% for itraconazole, 98.3% for flucytosine, and 96.4% for amphotericin B. For C. neoformans var. neoformans and T. beigelii, the agreement of the first-day reading was higher than that of the second-day reading for fluconazole (94 versus 92%, respectively, for C. neoformans var. neoformans, and 86.7 versus 80%, respectively, for T. beigelii). Our studies indicate that the microdilution technique performed following the NCCLS guidelines with a second-day reading is a valid alternative method for testing fluconazole, itraconazole, flucytosine, and amphotericin B against these eight species of yeasts.
A recent meeting jointly sponsored by the National Cancer Institute (NCI) and National Institute of Standards and Technology (NIST) brought together researchers active in nanotechnology and cancer molecular biology to discuss and evaluate the interface between disciplines. Emerging areas where nanotechnologies may impact cancer prevention and early cancer detection were elaborated by key researchers who catalyzed interdisciplinary dialogue aimed at fostering cross-discipline communications and future collaboration.
During the 10th European Colloquium on Cytogenetics of Domestic Animals held in Utrech, The Netherlands, in 1992, an international committee on river buffalo chromosomes was established. At the recent 8th North American Colloquium on Domestic Animal Cytogenetics and Gene Mapping in Guelph, Canada (1993), Q-, G- and R-banded river buffalo karyotypes were presented and discussed. This material was used to establish the first standard karyotype of the river buffalo.
The objective of the study was to characterize a low-cost and reliable working standard material for quality control of estrogen receptor (ER) determination with dextran-coated charcoal (DCC) and enzyme immunoassay (EIA) methods. Human fibromatous uterine lyophilized cytosol demonstrated good characteristics of stability and applicability for this purpose. Eleven laboratories participated in the intralaboratory and interlaboratory quality control study, and they achieved slightly higher coefficients of variation for ER-EIA (interlaboratory, 37.7%; intralaboratory, 22.9%) than for ER-DCC (interlaboratory, 24.2%; intralaboratory, 15.7%). There was an excellent correlation between ER results with ER-EIA and ER-DCC for 268 breast cancer biopsies. Quality assurance for ER assays using DCC techniques and immunometric methods with monoclonal antibodies (ER-EIA) can be set up with this available material of human origin to satisfy the characteristics of both techniques and the species specificity of monoclonal antibodies.
The randomized controlled trial (RCT) is not a gold standard: it is a good experimental design in some circumstances, but that's all. Potential shortcomings in the design and implementation of RCTs are often mentioned in passing, yet most researchers consider that RCTs are always superior to all other types of evidence. This paper examines the limitations of RCTs and shows that some types of evidence commonly supposed to be inferior to all RCTs are actually superior to many. This has important consequences for research methodology, for quality of care in clinical medicine, and--especially--for research funding policy. Because every study design may have problems in particular applications, studies should be evaluated by appropriate criteria, and not primarily according to the simplistic RCT/non-RCT dichotomy promoted by some prominent advocates of the evidence-based medicine movement and by the research evaluation guidelines based on its principles.
The Diabetes Control and Complications Trial (DCCT) and the United Kingdom Prospective Diabetes Study (UKPDS) demonstrated conclusively that risks for complications in patients with diabetes are directly related to glycemic control, as measured by glycated hemoglobin (GHb). Many diabetes organizations worldwide now recommend GHb targets in terms of DCCT/ UKPDS hemoglobin A1c (HbA1c). However, in 1993 there was a lack of comparability of GHb test results among methods and laboratories that represented a major obstacle to meaningful implementation of specific guidelines for diabetes care. The National Glycohemoglobin Standardization Program (NGSP) was implemented to enable laboratories to report DCCT/UKPDS-traceable GHb/HbA1c results. The number of methods and laboratories certified by the NGSP as traceable to the DCCT has steadily increased. Proficiency testing results show marked improvement in the comparability of GHb results. By the end of 2002, 98% of surveyed laboratories (n = approx. 2000) reported GHb results as HbA1c or equivalent compared to 50% in 1993. Ninety-seven percent of laboratories used an NGSP-certified method. For most certified methods in 2002, between-laboratory CVs were < 5%. For all certified methods in 2002, the mean HbA1c value (%) was within 0.8% HbA1c from the NGSP target at all HbA1c concentrations. The vast majority of laboratories in the US are now reporting results that are traceable to DCCT/UKPDS outcomes.
The stability of the International Reference Preparation of human TSH for immunoassay (previously distributed in ampoules coded 68/38) and of Research Standard A for HTSH has been examined by radioimmunoassay of accelerated degradation samples (stored as the dry ampouled preparations). Potency estimates on degradation samples suggest a high order of stability of immunopotency recognisable by two antisera (MRC 72/356 and Hunter 3A). For the International Reference Preparation the loss of immunopotency during storage at -20 degrees C is predicted to have been 0.56% per year.
OBJECTIVE: This study is the first comprehensive national survey of the organization, function, and composition of cleft palate and craniofacial teams in the U.S. and Canada. Complete descriptions of cleft and craniofacial teams are not currently provided in the literature, and this study will provide an overview for health services research and policy use. Conducted by a national organization, this study examines teams in detail using a pretested and standardized methodology. DESIGN: All known (n = 296) North American cleft palate and craniofacial teams were contacted for team listing purposes using a self-assessment method developed by an interdisciplinary committee of national stature. Team clinical leaders classified their teams into several possible categories and provided data on team care. The response rate was 83.4% (n = 247). RESULTS: The distribution of listed teams was: 105 (42.5%) cleft palate teams, 102 (41.3%) craniofacial teams (including craniofacial teams that are both cleft palate and craniofacial teams), 12 (4.9%) geographically listed teams, and 28 (11.3%) other teams (including interim cleft palate teams, low-density cleft palate teams, and evaluation and treatment review cleft palate teams). Eighty-five percent of all teams systematically collected and stored clinical data on their team's patient population in the past year. Furthermore, 50% of all teams had a quality assurance program in place to measure treatment outcomes. Other findings presented include the annual number of face-to-face team meetings; new and follow-up patient censuses; and surgical rates for initial repair of cleft lip/palate, orthognathic/osteotomy procedures, and intracranial/craniofacial procedures. CONCLUSIONS: Two of five North American teams classify themselves as having the capacity to provide both cleft palate and craniofacial care. An additional two of five teams limit their primary role to cleft palate care. Issues are raised regarding the distribution of teams, the regionalization of craniofacial services, health policy, and resource allocation.
The utility of the Groupamatic MG50 system for quantitative expression of agglutination in terms of continuous response was studied. By use of the characteristics of the design of this system, in which the change in voltage reflects the degree of agglutination, a linear regression relationship between the log ratio of light flux obtained by transformation of the voltage and the log dilution factor of the serum was demonstrated. The availability of the parallel line assay method to the standardization of the blood grouping antisera was also described.