PubMed Health⌕ Search

Biomedical subjects

R N Taylor

Publications and source records attributed to R N Taylor.

15 recordsLinked to original sources
PubMed1979

Center for Disease Control Diagnostic Immunology Proficiency Testing Program results for 1978.

Data from about 1,000 laboratories participating in the Diagnostic Immunology portion of the 1978 Center for Disease Control Proficiency Testing Program provided information dealing with laboratory performance and trends in testing protocols. Ninety specimens were distributed in scheduled quarterly and semiannual shipments, and five additional specimens were provided in a special survey. The specimens offered both qualitative and quantitative challenges for a wide variety of analytes which included syphilis serology, rheumatoid factor, bacterial agglutinins, hepatitis B surface antigen, immunoglobulins and other serum proteins, infectious mononucleosis, rubella, toxoplasma, antinuclear antibodies, and streptococcal exoenzymes. This paper summarizes the results of the 1978 program.

Agglutinins↗
PubMed1978

Reference preparation to standardize results of serological tests for rheumatoid factor.

The variance of between-laboratory results for rheumatoid factor tests was reduced through the use of a reference serum preparation. Two separate proficiency testing surveys have shown reduction of 58 to 81% in variance with samples of differing levels and composition. Reduction of variance was seen in data from laboratories in which the same methods and reagents were used, but greater reduction in variance was seen in results from laboratories using different methods and reagents. This study demonstrates that comparability of results of rheumatoid factor tests can be significantly improved through the use of a standard reference serum preparation and that confidence in such results can therefore be increased. A serum rheumatoid factor level of approximately 50 IU/ml is equivalent to a titer of 160 in the Singer-Plotz latex test, which has traditionally been accepted as evidence of rheumatoid arthritis.

Arthritis, Rheumatoid↗
PubMed1978

Comparison of kinetic and end-point diffusion methods for quantitating human serum immunoglobulins.

Proficiency testing results were used to compare the kinetic and end-point versions of the single radial immunodiffusion method for quantitating human serum immunoglobulins. Statistical analysis of the results indicated that the results were not normally distributed but that the log normal distribution gives the best fit of any of the well-known frequency distributions. Consequently, statistical analysis of immunoglobulin results must be log transformed before parametric statistical tests can be appropriately applied. In general, there were no significant differences in level, precision, or interlaboratory comparability for these two methods. However, levels were different for participants using Hyland reagents, and better interlaboratory comparability was achieved by the end-point assay for immunoglobulin M. There were no significant differences in reported levels when compared by manufacturer within the same method.

Humans↗
PubMed1978

Center for Disease Control Diagnostic Immunology Proficiency Testing Program results for 1977.

A summary of the yearly data accumulated and analyzed in the diagnostic immunology portion of the Center for Disease Control 1977 Proficiency Testing Program provides information on the trends in testing protocols from over 900 participating laboratories. One hundred and fourteen specimens prepared by the Center for the Disease Control were distributed quarterly or in special surveys. The specimens chosen provided feedback from a broad range of tests commonly performed in diagnostic immunology laboratories and included those for rubella antibodies, hepatitis B surface antigen, bacterial antibodies, rheumatoid factor, immunoglobulins and other serum-specific proteins, syphilis serology, and carcinoembryonic antigen. This summary provides an overview of the trends observed since last year's report.

Centers for Disease Control and Prevention, U.S.↗
PubMed1977

Changes in menstrual cycle length and regularity after use of oral contraceptives.

This is an analysis of changes in menstrual cycle length and regularity occurring for a group of 211 women who had discontinued use of oral contraceptives. The analysis is based on prospectively recorded histories from the Menstruation and Reproduction History Program. Post-pill menstrual cycle length and regularity are compared with pre-pill averages. In the first post-pill cycle, there was an average increase of 6 days in cycle length. In subsequent cycles, however, cycle length and regularity were comparable to pre-pill norms in most cases.

Adult↗
PubMed1977

The risk of post-pill amenorrhea: a preliminary report from the Menstruation and Reproduction History Research Program.

Menstrual cycle lengths prior to and after oral contraceptive use were prospectively recorded for 245 women. In this preliminary study, a difference in the distributions in the pre- and post-pill cycle lengths was observed. An increase of 5 days in the medial cycle length occurred after oral contraceptive use had been discontinued. Although there was an approximately twofold relative risk of amenorrhea of 90 days' duration or more after discontinuing pill use, the differences in the rates of amenorrhea between the pre-pill and post-pill cycles were not statistically significant.

Adult↗
PubMed1977

Reduction of variation in results of rheumatoid factor tests by use of a serum reference preparation.

Standaridizing test results for rheumatoid factor by comparing results obtained for an unknown with results obtained for a serum reference preparation decreased variance between laboratories, as measured in the Center for Disease Control proficiency testing program, by 77%. The amount of improvement was also estimated by the type of test and by the manufacturer's product. Standardization resulted in an increase in the number of reported results that were within a twofold dilution of the median value. The percentage increased from 50.3 to 93.7% for the slide tests and from 78.1 to 91.2% fro the tube tests. Decrease in variance by manufacturer's product ranged from 94 to 27%. The study demonstrated that adopting a reference serum standard could substantially improve the comparability of rheumatoid factor test results and that proficiency testing programs can be used to estimate improvement which could be expected as a result of standardization.

Analysis of Variance↗
PubMed1977

Results of a nationwide proficiency test for carcinoembryonic antigen.

A proficiency testing survey for carcinoembryonic antigen (CEA) was conducted by the Center for Disease Control. The results from 125 laboratories throughout the United States indicate that many laboratories perform satisfactorily, but some laboratories need substantial improvement. Failure to follow manufacturer's recommendations and failure to heed the indications of "out of control" control results were two of the reasons for poor performance. Results reported for samples with CEA levels of larger than or equal to 20 ng/ml showed that the direct method produced significantly higher values than the indirect method on either whole of diluted plasma. Almost one-fourth of the results reported in this survey were placed in the wrong nominal group. It was determined that the results were log normally distributed and, consequently, that statistical methods that are appropriate for this distribtuion should be used for the analysis of CEA results. Most of the variation observed was the result of poor comparability between laboratories rather than lack of precision within the laboratory. This indicates that better performance could be achieved by better standardization and closer adherence to established procedures.

Carcinoembryonic Antigen↗
PubMed1977

Center for disease control diagnostic immunology proficiency testing program results for 1976.

Over 900 laboratories participated in the Diagnostic Immunology portion of the 1976 Proficiency Testing Program, which was provided by the Center of Disease Control under the authority of the Clinical Laboratories Improvement Act of 1967. One hundred specimens prepared by the Center for Disease Control for analysis were distributed on a quarterly schedule or in special surveys. Feedback from participating laboratories included over 37,500 qualitative and 33,000 quantitative responses, which were analyzed to determine individual laboratory proficiency levels. In addition, information supplied by participants in each survey helped to delineate trends in testing protocols. The specimens chosen for analysis called for a broad range of tests commonly performed in diagnostic immunology laboratories, including those for rubella antibodies, hepatitis B surface antigen, bacterial antibodies, rheumatoid factor, immunoglobulins and other serum-specific proteins, and carcinoembryonic antigen. A summary of the data analysis is provided so that the laboratories can improve their overall performance levels.

Agglutination Tests↗
PubMed1976

Results of the Center for Disease Control Proficiency Testing Program for the detection of hepatitis B surface antigen.

The changes in the types and numbers of tests used by participants in the Center for Disease Control Proficiency Testing Program for the detection of hepatitis B surface antigen from the beginning of the program in 1971 until October 1975 are analyzed; the implications of these changes are discussed. Changes in the use of agar gel diffusion, rheophoresis, counterelectrophoresis, complement fixation, reverse passive latex agglutination, radioimmunoassay, and reverse passive hemagglutination tests are reviewed. The performance of the participants for 1975 is reported, and factors related to performance (type or combinations of tests used, procedures used to confirm specificity, etc.) are discussed. The increase in the use of third-generation tests in place of tests with lower sensitivity and the decrease in the use of multiple tests undoubtedly represent increased efficiency and effectiveness.

Blood Donors↗
PubMed1975

Mites in the environment of cases of Norwegian scabies.

Three cases of Norwegian Scabies diagnosed in Glasgow hospitals within 1 year each caused wide-spread outbreaks of papular eruptions amongst the patients and staff, followed later by a few cases of classical scabies. Symptoms and timing suggested that these infections were caused by immature mites derived by personal contact and possibly by contact with infected cuticular fragments which were abundant in the environment of the three patients. To control a ward epidemic, isolation of the Norwegian scabietic should be followed by environmental and then by personal disinfestation.

Aged↗