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PubMed2002

Whose drinking does the liberalization of alcohol policy increase? Change in alcohol consumption by the initial level in the Finnish panel survey in 1968 and 1969.

AIMS: To study how the annual volume of alcohol consumed changed among population groups in different categories of initial consumption in a situation where per capita consumption strongly increased due to a new alcohol law. DESIGN: A post-hoc quasi-experiment with a two-wave panel study. The regression to the mean effect was accounted for by using reference data from two auxiliary panel studies. SETTING: Finland in 1968 and 1969, when per capita consumption increased by 46% in a year. Reference data come from Norway in 1975 and 1976, and the United States in 1993 and 1994. PARTICIPANTS: General population sample of 1720 (1292 men) aged 15-69 (response rate 91.4%). REFERENCE DATA: General population surveys in a Norwegian town (n=254) and in the United States (n=658). MEASUREMENTS: Annual volume of alcohol consumed. FINDINGS: In Finland, the greatest change in observed consumption levels occurred among those with moderate consumption levels, but the same phenomenon was observed in the reference data. A comparison between the Finnish and the reference data indicated that in Finland consumption increased at all levels, and the higher the initial consumption level, the greater the increase. CONCLUSIONS: A best estimate for the differential impact of future increases in alcohol consumption is that moderate and particularly heavy drinkers will be affected to a greater extent than will light drinkers or abstainers.

Adolescent↗
PubMed2000

Case studies in orthotopic liver transplantation for hepatitis B: a panel discussion.

Five cases that were referred to the Division of Transplantation at NYU School of Medicine for consideration for liver transplantation were discussed among a panel of hepatitis B and liver transplant experts. Opinions were obtained on the management at every stage of treatment of patients with the following initial information: Case one: young Asian woman in stage IV hepatic coma; intubated; prothrombin time (PT): 30 s; serum glutamic oxaloacetic transaminase (SGOT): 8,000 IU; total bilirubin: 25 mg/dL; hepatitis B surface antigen (HBsAg) positive. Case two: 70-yr-old woman, native of Greece; decompensated cirrhosis with encephalopathy; Child-Pugh Class C; HBsAg positive; hepatitis B surface antibody (HBsAb) negative; hepatitis B e antigen (HBeAg) positive; hepatitis B e antibody (HBeAb) negative; hepatitis B virus (HBV) DNA titer: 10,000. Case three: Muscular detective working full-time; cirrhosis; Child Pugh Class B; ascites controlled with spironolactone and furosemide; PT: 19s; HBsAg positive; HBsAb negative; HBV DNA titer: 50,000; low platelet count. Case four: 45-yr-old baker; cirrhosis and resectable 4-cm hepatoma; Child-Pugh Class B; PT: 16 s; Blood type O; United Network for Organ Sharing (UNOS) 2B; HBV DNA titer: 3,000. Case five: 40-yr-old Indian man; 300 pounds with massive ascites; Child Pugh Class C; PT: 17 s; HBsAg positive; HBV DNA titer: 22,000; transplanted with intra-operative hypotension; tacrolimus; graft functioning; HBIg 10,000 IU intra-operative and around the clock during the first post-operative week; required huge doses of hepatitis B immune globulin (HBIg) to maintain adequate HBsAb level; daily loss of 5 6 L of ascites fluid; post-operative day 8: anuric, blood urea nitrogen (BUN) 127, creatinine 3, mental status changes.

Adult↗
PubMed1992

Accuracy of asthma statistics from death certificates in South Australia.

OBJECTIVE: To assess the accuracy of asthma statistics from death certificates in South Australia. DESIGN: Comparison of death certificate coding with expert panel assessments of causes of death after interviews with certifying doctors, regular medical practitioners and close acquaintances of the deceased. SUBJECTS: 261 subjects for whom the term "asthma", "asthmatic" or "asthmaticus" was recorded in Part I or Part II of death certificates lodged in the 24-month period from May 1988. MAIN OUTCOME MEASURES: Sensitivity, specificity and predictive value of death certificate coding, with expert panel assessments as the reference standard. RESULTS: About 95% of deaths assessed as definitely due to asthma were so coded from death certificates, but only 69% of deaths assessed by the panel as not due to asthma were coded to a "non-asthmatic" cause. Of the 129 deaths coded to asthma, the percentage assessed as definitely or likely to be due to asthma was 56%. For ages under 65 years, this figure was 84% compared with only 38% for older subjects. CONCLUSION: The accuracy of death certificate data on asthma for the age group 65 years and over would be too low at present for most epidemiological purposes.

Abstracting and Indexing↗
PubMed2003

The data warehouse as a foundation for population-based reference intervals.

The volume of data contained in a data warehouse represents a potential resource to provide the basis for detailed and specific reference intervals. Routine chemistry panel testing data were derived from an outreach laboratory patient population of 438,180 people and then screened by multiple data filters to identify a large and demographically diverse reference population. Reference intervals were determined for 4 common analytes: aspartate aminotransferase, alanine aminotransferase, total bilirubin, and alkaline phosphatase. Each derived reference population contained more than 60,000 people with sex- and age-specific subgroups comprising between 495 and 4,949 persons. These intervals are particularly representative of the aging patient population and demonstrate a degree of age and sex diversity not reflected commonly in routine laboratory reference intervals. Warehouse data also can yield other interpretative data, such as percentile ranking of results or disease-specific reference intervals. As the warehouse accumulates data from other disciplines (such as from clinical notes or pharmacy), there is increasing potential for the laboratory to enhance the clinician's ability to diagnose and treat disease.

Adolescent↗
PubMed1996

[Practical subjects of reference interval].

A concept of reference interval was first proposed by Dybkaer in 1973 in order to avoid an ambiguous definition of so-called normal range. This concept was succeeded by IFCC Expert Panel on Theory of Reference Value and the recommendation for the concept of reference value was documented in 1987 from IFCC scientific committee. Finally, NCCLS proposed the document for Reference Interval, how to determine, utilize the reference interval in clinical laboratory, in 1992. In this paper, how to determine and utilize the reference interval in clinical laboratory are described and discussed based on the concepts of NCCLS and IFCC.

Humans↗
PubMed1986

Susceptibility testing of methicillin-resistant Staphylococcus aureus with three commercial microdilution systems.

The antimicrobial susceptibilities of 100 methicillin-resistant Staphylococcus aureus isolates were determined concurrently by API Uniscept KB, Micro-Media, MicroScan, standardized disk diffusion, and reference broth microdilution to evaluate whether these commercial microdilution systems would reliably defect methicillin-resistant S. aureus. The methicillin minimal inhibitory concentration for all isolates was greater than or equal to 16 micrograms/ml as determined by the reference minimal inhibitory concentration panels containing 2% NaCl supplemented Mueller-Hinton broth. Using the breakpoints established by the National Committee for Clinical Laboratory Standards for reporting susceptible and resistant methicillin results, there was 100% agreement between the reference methods and API Uniscept KB at 24 hr. The Micro-Media and MicroScan systems had 47% and 8% very major discrepancies at 24 hr, respectively. At 48 hr, these two systems exhibited 15% and 0% very major discrepancies. Micro-Media and MicroScan were in agreement with the reference microdilution method (+/- 1 log2 dilution) for 62% and 68% of the strains at 24 hr, respectively and 88% and 85% of the isolates at 48 hr, respectively. The results of this study indicate that API Uniscept KB would provide a practical and reliable method for the detection of methicillin-resistant S. aureus.

Anti-Bacterial Agents↗
PubMed1989

Health-based reference values of the Mini-Finland Health Survey: 1. Serum gamma-glutamyltransferase, aspartate aminotransferase and alkaline phosphatase.

The reference values for gamma-glutamyltransferase (GT), aspartate aminotransferase (ASAT) and alkaline phosphatase (AFOS) activities in serum have been produced on the basis of measurements done in the Mini-Finland Health Survey. A representative sample of all Finns aged 30 years or over comprised 8000 persons, of whom 99.2% participated in the actual health survey. Every effort was made to obtain reference values for the healthy ambulatory population. Three separate health-derived selection criteria were used to obtain such reference values for the above-mentioned enzymes: those based on the available literature, with minor modifications, the recommendations published by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, criteria that were obtained after subgroup comparisons of the obtained data, where all the factors affecting the enzyme levels were identified. The recommendations of the Expert Panel on Theory of Reference Values (1987) were strictly adhered to in the statistical analyses. The distribution of the serum activity of GT was very skewed. The overall intervals for men and women were 5.1-1460 and 4.7-748 U/l, respectively. The frequency distributions could be transformed to the normal ones logarithmically. The 95% inner reference intervals for GT in the three groups were 7-76, 7-65, and 8-57 U/l for men and 6-35, 6-30 and 6-32 U/l for women, respectively. For ASAT the full intervals of the enzyme levels in serum were 2.6-770 U/l for men and 8.3-172 U/l for women. After logarithmic transformation the respective reference intervals in the three selection groups were 14-42, 14-40 and 13-39 U/l for men and 13-33, 12-31 and 13-33 U/l for women. The full intervals of AFOS were 47.5-2755 and 5.4-816 U/l for men and women, respectively; after the logarithmic transformation the reference intervals of the three selection groups were 98-267, 97-254 and 97-264 U/l for men and 77-265, 75-231 and 75-250 U/l for women, respectively.

Adult↗
PubMed1994

Rapid tests for the diagnosis of Legionella infections.

Three rapid tests are now available for the diagnosis of Legionella infections: direct fluorescent antibody (DFA) assay, culture on selective media, and urinary antigen detection. A combination of the three tests constitutes a "Legionella Panel." The objective of this article is to present our experience with these assays and to discuss experimental tests that may further improve our capability to diagnose Legionnaires' disease. Diagnoses of Legionella infections were done in 11 of 549 Legionella panels submitted to our reference laboratory. Six were positive for urinary antigen with corresponding negative DFA and culture; three had a positive DFA with negative culture and urinary antigen; and two had positive reactions for all three tests. The use of the Legionella panel offers a rapid, sensitive, and specific diagnosis of infection. The amplification of Legionella DNA in respiratory samples by the polymerase chain reaction method is a new diagnostic test that will further improve our ability to recognize and treat patients with Legionella infections.

Antigens, Bacterial↗
PubMed1986

Mononuclear cell phenotypes in patients with psoriasis.

Mononuclear blood cells from 19 patients with psoriasis were stained with a panel of monoclonal antibodies which detect total T lymphocytes, their helper/inducer and suppressor/cytotoxic subsets and Ia-positive lymphocytes and monocytes. Fluorescence-positive cells were enumerated by cell flow cytometry. In these patients, percentages of all mononuclear cell studies were within reference range with few, sporadic exceptions. Statistical analysis of data showed no significant differences between patient values and reference values from a panel of 100 normal subjects.

Adult↗
PubMed2001

Osteoporosis prevention, diagnosis, and therapy.

OBJECTIVES: To clarify the factors associated with prevention, diagnosis, and treatment of osteoporosis, and to present the most recent information available in these areas. PARTICIPANTS: From March 27-29, 2000, a nonfederal, nonadvocate, 13-member panel was convened, representing the fields of internal medicine, family and community medicine, endocrinology, epidemiology, orthopedic surgery, gerontology, rheumatology, obstetrics and gynecology, preventive medicine, and cell biology. Thirty-two experts from these fields presented data to the panel and an audience of 699. Primary sponsors were the National Institute of Arthritis and Musculoskeletal and Skin Diseases and the National Institutes of Health Office of Medical Applications of Research. EVIDENCE: MEDLINE was searched for January 1995 through December 1999, and a bibliography of 2449 references provided to the panel. Experts prepared abstracts for presentations with relevant literature citations. Scientific evidence was given precedence over anecdotal experience. CONSENSUS PROCESS: The panel, answering predefined questions, developed conclusions based on evidence presented in open forum and the literature. The panel composed a draft statement, which was read and circulated to the experts and the audience for public discussion. The panel resolved conflicts and released a revised statement at the end of the conference. The draft statement was posted on the Web on March 30, 2000, and updated with the panel's final revisions within a few weeks. CONCLUSIONS: Though prevalent in white postmenopausal women, osteoporosis occurs in all populations and at all ages and has significant physical, psychosocial, and financial consequences. Risks for osteoporosis (reflected by low bone mineral density [BMD]) and for fracture overlap but are not identical. More attention should be paid to skeletal health in persons with conditions associated with secondary osteoporosis. Clinical risk factors have an important but poorly validated role in determining who should have BMD measurement, in assessing fracture risk, and in determining who should be treated. Adequate calcium and vitamin D intake is crucial to develop optimal peak bone mass and to preserve bone mass throughout life. Supplementation with these 2 nutrients may be necessary in persons not achieving recommended dietary intake. Gonadal steroids are important determinants of peak and lifetime bone mass in men, women, and children. Regular exercise, especially resistance and high-impact activities, contributes to development of high peak bone mass and may reduce risk of falls in older persons. Assessment of bone mass, identification of fracture risk, and determination of who should be treated are the optimal goals when evaluating patients for osteoporosis. Fracture prevention is the primary treatment goal for patients with osteoporosis. Several treatments have been shown to reduce the risk of osteoporotic fractures, including those that enhance bone mass and reduce the risk or consequences of falls. Adults with vertebral, rib, hip, or distal forearm fractures should be evaluated for osteoporosis and given appropriate therapy.

Adult↗
PubMed1981

Alpha fetoprotein screening and diagnosis of fetal open neural tube defects: the need for quality control.

A workshop, held in May, 1978, at the National Institute of Child Health and Human Development, considered the quality control of reagents and assays for measuring alpha fetoprotein (AFP) in maternal serum and amniotic fluid for the antenatal screening and diagnosis of open neural tube defects. The recommendations, published in detail elsewhere and summarized in this article, were based on what was known to be readily achievable and on estimates of the effect of assay performance on screening and diagnostic sensitivity and specificity. Main points considered included: (1) choice of units for AFP measurement and interpretation, (2) need for National AFP Reference Preparations and the need for a scientific panel to assess the adequacy of these reference materials, (3) information needed from reagent manufacturers, (4) criteria for assay performance, (5) biological sources of reagents, (6) need for laboratory and epidemiologic monitoring, and (7) need for a minimum assay workload.

Amniotic Fluid↗
PubMed1993

Establishing reference values from adults: recommendation on procedures for the preparation of individuals, collection of blood, and handling and storage of specimens. Committee on Reference Values of the Scandinavian Society for Clinical Chemistry.

The concentrations of blood components are influenced by a number of preanalytical factors, the importance of which varies [1]. Therefore it is necessary to standardize the specimen collection, as was done by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, which in 1975 published its recommendation on the production of reference values in clinical chemistry [2]. It was the very first recommendation of its kind. Since then, new information has accumulated, and it has become necessary to revise the part concerning the preparation of subjects for blood collection, the collection procedure itself, and the subsequent handling of the specimen. Also, The International Federation of Clinical Chemistry (Expert Panel on Theory of Reference Values) has produced its own recommendation [3]. The recommendation described below replaces pp. 39-44 of the former Scandinavian recommendation [2]. The procedure described below is designed for the collection of specimens for the measurement of the majority of components in blood and specimen collection from the cubital vein is described. It can be easily adapted for the collection of blood from other vessels [4]. Certain laboratory investigations require a special protocol. In that case, the preparation of the subject prior to and during specimen collection as well as the procedure itself should be described in sufficient detail to permit reproduction by adequately trained personnel. In any project designed to produce reference values the same protocol for the preparation of individuals and specimen collection should be used throughout the project. The protocol should be described in detail. Thus, it is not satisfactory to state only that the present recommendation was followed. Each section of the recommendation is followed by a check list for points which should be taken into account.

Adult↗
PubMed2006

Evaluation of patients treated with natalizumab for progressive multifocal leukoencephalopathy.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) was reported to have developed in three patients treated with natalizumab. We conducted an evaluation to determine whether PML had developed in any other treated patients. METHODS: We invited patients who had participated in clinical trials in which they received recent or long-term treatment with natalizumab for multiple sclerosis, Crohn's disease, or rheumatoid arthritis to participate. The clinical history, physical examination, brain magnetic resonance imaging (MRI), and testing of cerebrospinal fluid for JC virus DNA were used by an expert panel to evaluate patients for PML. We estimated the risk of PML in patients who completed at least a clinical examination for PML or had an MRI. RESULTS: Of 3417 patients who had recently received natalizumab while participating in clinical trials, 3116 (91 percent) who were exposed to a mean of 17.9 monthly doses underwent evaluation for PML. Of these, 44 patients were referred to the expert panel because of clinical findings of possible PML, abnormalities on MRI, or a high plasma viral load of JC virus. No patient had detectable JC virus DNA in the cerebrospinal fluid. PML was ruled out in 43 of the 44 patients, but it could not be ruled out in one patient who had multiple sclerosis and progression of neurologic disease because data on cerebrospinal fluid testing and follow-up MRI were not available. Only the three previously reported cases of PML were confirmed (1.0 per 1000 treated patients; 95 percent confidence interval, 0.2 to 2.8 per 1000). CONCLUSIONS: A detailed review of possible cases of PML in patients exposed to natalizumab found no new cases and suggested a risk of PML of roughly 1 in 1000 patients treated with natalizumab for a mean of 17.9 months. The risk associated with longer treatment is not known.

Antibodies, Monoclonal↗
PubMed1999

Multicenter comparison of the sensititre YeastOne Colorimetric Antifungal Panel with the National Committee for Clinical Laboratory standards M27-A reference method for testing clinical isolates of common and emerging Candida spp., Cryptococcus spp., and other yeasts and yeast-like organisms.

National Committee for Clinical Laboratory Standards (NCCLS) standard guidelines are available for the antifungal susceptibility testing of common Candida spp. and Cryptococcus neoformans, but NCCLS methods may not be the most efficient and convenient procedures for use in the clinical laboratory. MICs of amphotericin B, fluconazole, flucytosine, itraconazole, and ketoconazole were determined by the commercially prepared Sensititre YeastOne Colorimetric Antifungal Panel and by the NCCLS M27-A broth microdilution method for 1,176 clinical isolates of yeasts and yeast-like organisms, including Blastoschizomyces capitatus, Cryptococcus spp., 14 common and emerging species of Candida, Hansenula anomala, Rhodotorula spp., Saccharomyces cerevisiae, Sporobolomyces salmonicolor, and Trichosporon beigelii. Colorimetric MICs of amphotericin B corresponded to the first blue well (no growth), and MICs of the other agents corresponded to the first purple or blue well. Three comparisons of MIC pairs by the two methods were evaluated to obtain percentages of agreement: 24- and 48-h MICs and 24-h colorimetric versus 48-h reference MICs. The best performance of the YeastOne panel was with 24-h MICs (92 to 100%) with the azoles and flucytosine for all the species tested, with the exception of C. albicans (87 to 90%). For amphotericin B, the best agreement between the methods was with 48-h MIC pairs (92 to 99%) for most of the species tested. The exception was for isolates of C. neoformans (76%). These data suggest the potential value of the YeastOne panel for use in the clinical laboratory.

Amphotericin B↗
PubMed2006

Constraints on transportation of reagents, reference materials and samples, difficulties and possible solutions: a user's perspective.

The air transportation of infectious materials is regulated by international air transport associations and based on United Nations Model regulations which have become more practical in addressing animal disease agents. However, individual countries' import and interstate requirements determine what materials can be imported and transported, and this approval process can be long, resulting in delays in organism confirmation, use of international OIE and other reference laboratories, and acquisition of reference materials, proficiency test panels, and reagents for performing necessary testing. Delays can be prevented for permits that are required for the routine work performed by a laboratory through the use of comprehensive and annually renewed permits. This process, however, does not address new and exotic agents where time is critical to an effective emergency response. This paper suggests actions by both the OIE and regulatory authorities which can assist in streamlining and expediting the permit process.

Aircraft↗
PubMed1996

Bioelectrical impedance analysis in body composition measurement: National Institutes of Health Technology Assessment Conference Statement.

The objective of this conference was to provide physicians with a responsible assessment of bioelectrical impedance analysis (BIA) technology for body composition measurement. Participants were a non-Federal, nonadvocate, 13-member panel representing the fields of nutrition, pediatrics, surgery, public health, biomedical engineering, epidemiology, and biostatistics. In addition, 20 experts in nutrition, pediatrics, metabolism, biomedical engineering, physiology, and epidemiology presented data to the panel and a conference audience of 220. The literature was searched through Medline and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. The panel, answering predefined questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. The panel concluded that BIA provides a reliable estimate of total body water under most conditions. It can be a useful technique for body composition analysis in healthy individuals and in those with a number of chronic conditions such as mild-to-moderate obesity, diabetes mellitus, and other medical conditions in which major disturbances of water distribution are not prominent. BIA values are affected by numerous variables including body position, hydration status, consumption of food and beverages, ambient air and skin temperature, recent physical activity, and conductance of the examining table. Reliable BIA requires standardization and control of these variables. A specific, well-defined procedure for performing routine BIA measurements is not practiced. Therefore, the panel recommends that a committee of appropriate scientific experts and instrument manufacturers be formed with the goal of setting instrument standards and procedural methods.

Body Composition↗
PubMed1999

Survey of serum potassium reference measurements.

We compared the quality of reference measurements for serum potassium in four reference laboratories from three different European countries, using a panel of 60 native patients' samples. The reference methods were based on either ion chromatography (one laboratory) or flame atomic emission spectrometry (three laboratories). Performance specifications for serum potassium measurements were defined as a maximum overall coefficient of variation (CV) of 1.5%, a maximum bias of 0.65% and a maximum total error of 3.0%. The overall imprecision for all laboratories was in the range of 0.7 to 1.3%, and was thus below the proposed specification of 1.5%. However, two laboratories reported 12 and 13 quadruplicates with CVs exceeding this limit. The mean bias (expressed as deviation from the overall mean of all laboratories) for all reference laboratories was < 0.65%. In the lower concentration range, however, one laboratory exceeded this limit. No laboratory measured samples with a total error above 3.0%. From these results, it can be concluded that the reference measurements, and, thus, also the reference methodologies, based on ion chromatography and flame atomic emission spectrometry were equivalent, and able to satisfy current analytical specifications for serum potassium measurements.

Chromatography, Liquid↗