Rabies vaccine standards: Comparison of the 5th and 6th WHO international reference standards to the USDA veterinary reference standard

Abstract Context: Thyroglobulin (Tg) may be a valuable indicator of improving thyroid function in children after salt iodization. A recently developed Tg assay for use on dried whole blood spots (DBS) makes sampling practical, even in remote areas. Objective: The study aim was to develop a reference standard for DBS-Tg, establish an international reference range for DBS-Tg in iodine-sufficient children, and test the standardized DBS-Tg assay in an intervention trial. Design, Participants, and Interventions: Serum Tg reference material of the European Community Bureau of Reference (CRM-457) was adapted for DBS and its stability tested over 1 yr. DBS-Tg was determined in an international sample of 5- to 14-yr-old children (n = 700) who were euthyroid, anti-Tg antibody negative, and residing in areas of long-term iodine sufficiency. In a 10-month trial in iodine-deficient children, DBS-Tg and other indicators of iodine status were measured before and after introduction of iodized salt. Results: Stability of the CRM-457 Tg reference standard on DBS over 1 yr of storage at −20 and −50 C was acceptable. In the international sample of children, the third and 97th percentiles of DBS-Tg were 4 and 40 μg/liter, respectively. In the intervention, before introduction of iodized salt, median DBS-Tg was 49 μg/liter, and more than two thirds of children had DBS-Tg values greater than 40 μg/liter. After 5 and 10 months of iodized salt use, median DBS-Tg decreased to 13 and 8 μg/liter, respectively, and only 7 and 3% of children, respectively, had values greater than 40 μg/liter. DBS-Tg correlated well at baseline and 5 months with urinary iodine and thyroid volume. Conclusions: The availability of reference material and an international reference range facilitates the use of DBS-Tg for monitoring of iodine nutrition in school-age children.

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Calibrating NIST SRM 683 as a new international reference standard for Zn isotopes

Journal of Analytical Atomic Spectrometry ◽

10.1039/c8ja00249e ◽

2018 ◽

Vol 33 (10) ◽

pp. 1777-1783 ◽

Cited By ~ 5

Author(s):

Yuhan Yang ◽

Xingchao Zhang ◽

Sheng-Ao Liu ◽

Ting Zhou ◽

Haifeng Fan ◽

...

Keyword(s):

Reference Standard ◽

Environmental Sciences ◽

International Reference ◽

Zinc Isotopes ◽

Zn Isotopes

Zinc isotopes have been increasingly applied in cosmochemistry, geochemistry, and environmental sciences.

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Assessment of Protein Quality Methodology for Infant Formulas

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/68.4.680 ◽

1985 ◽

Vol 68 (4) ◽

pp. 680-683

Author(s):

Geraldine Vaughan Mitchell ◽

Mamie Young Jenkins

Keyword(s):

Quality Evaluation ◽

Protein Quality ◽

Reference Standards ◽

Infant Formulas ◽

Casein Diet ◽

Reference Standard ◽

Powdered Milk ◽

The Third ◽

Net Protein

Abstract Rat bioassay was used to assess the protein quality of powdered infant formulas and to evaluate the feasibility of using modified casein diets (containing the same source and level of fat and carbohydrate contributed by the infant formulas) as reference standards. Modification of the casein diet to match the milk-based formulas caused a significant reduction in weekly protein efficiency ratios (PER) and net protein ratios (NPR) at the third and fourth weeks. Modification of the casein diet to simulate the soy-based formulas had no significant effect on NPR values; PER values were more varied. When PER and NPR values of the powdered milk-based formulas were expressed relative to the unmodified reference standard, the relative values were lower than when each matched reference was used. With few exceptions, the relative weekly PER values of the soy-based formulas were similar regardless of the standard used. The relative NPR values of the formulas had a pattern similar to the relative PER values. The data indicate that protein quality evaluation of infant formulas using rat bioassay warrants the use of matched casein reference diets for each type of formula.

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Production of a proposed International Reference Standard Altenaria extract

Journal of Allergy and Clinical Immunology ◽

10.1016/0091-6749(88)91035-4 ◽

1988 ◽

Vol 81 (4) ◽

pp. 651-663 ◽

Cited By ~ 17

Author(s):

Ricki M. Helm ◽

Diane L. Squillace ◽

John W. Yunginger

Keyword(s):

Reference Standard ◽

International Reference

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Chinese Preschool Children Growth Reference Standard and Related Curve: Based on GAMLSS Approach

Iranian Journal of Public Health ◽

10.18502/ijph.v50i6.6424 ◽

2021 ◽

Author(s):

Sanhua Zhang ◽

Chongmin Jiang ◽

Chunjing Tu

Keyword(s):

Preschool Children ◽

Growth And Development ◽

Reference Standards ◽

Chest Circumference ◽

Reference Standard ◽

Sitting Height ◽

Growth Reference ◽

Percentile Curve ◽

And Control ◽

Height For Age

Background: The current national growth and development standard of preschool children in China was formulated in 2003, which has many deficiencies. It is necessary to construct more scientific percentile curve and growth reference standards in order to evaluate more effectively the growth, development and health status of Chinese children. Methods: Based on the physical and health data of 31 provinces in China measured in 2010 and 2014, the GAMLSS model was used to construct the growth reference standard and correlation curve. Results: We obtained growth reference standards for percentile curve and Z-score curve of height-for-age, sitting height-for-age, Weight-for-age, Chest circumference-for-age of Chinese preschool children. The C50 percentile of all indicators showed an obvious increasing trend with aged 3.0 to 6.5. Such as, the height of boys and girls increased by 21.1cm and 20.3cm respectively, the sitting height boys and girls increased by 10.3cm and 10.1cm respectively, the weight of boys and girls increased by 7.1 kg and 6.3 kg respectively, the Chest circumference of boys and girls increased by 6cm and 5.2 cm respectively. Conclusion: The children's growth and development charts provided in this study provide effective monitoring and personalized evaluation tools for the growth and development assessment of preschool children, as well as for the reduction of malnutrition, prevention and control of childhood obesity. It is recommended to be used in some areas such as child health, medical treatment and public health.

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Evaluation and adoption of a new international reference standard for bovine tuberculin

Bulletin de l OIE ◽

10.20506/bull.2016.2.2517 ◽

2016 ◽

Vol 2016 (2) ◽

pp. 57-60

Author(s):

Keyword(s):

Reference Standard ◽

International Reference ◽

Bovine Tuberculin

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Utility of Composite Reference Standards and Latent Class Analysis in Evaluating the Clinical Accuracy of Diagnostic Tests for Pertussis

Clinical and Vaccine Immunology ◽

10.1128/cvi.00223-07 ◽

2007 ◽

Vol 15 (1) ◽

pp. 106-114 ◽

Cited By ~ 46

Author(s):

Andrew L. Baughman ◽

Kristine M. Bisgard ◽

Margaret M. Cortese ◽

William W. Thompson ◽

Gary N. Sanden ◽

...

Keyword(s):

Latent Class Analysis ◽

Diagnostic Tests ◽

Latent Class ◽

Disease Status ◽

Standard Test ◽

Reference Standards ◽

Class Analysis ◽

Reference Standard ◽

Internal Reference ◽

Clinical Sensitivity

ABSTRACT Numerous evaluations of the clinical sensitivity and specificity of PCR and serologic assays for Bordetella pertussis have been hampered by the low sensitivity of culture, the gold standard test, which leads to biased accuracy estimates. The bias can be reduced by using statistical approaches such as the composite reference standard (CRS) (e.g., positive if culture or serology positive; negative otherwise) or latent class analysis (LCA), an internal reference standard based on a statistical model. We illustrated the benefits of the CRS and LCA approaches by reanalyzing data from a 1995 to 1996 study of cough illness among 212 patients. The accuracy of PCR in this study was evaluated using three reference standards: culture, CRS, and LCA. Using specimens obtained 0 to 34 days after cough onset, estimates of the sensitivity of PCR obtained using CRS (47%) and LCA (34%) were lower than the culture-based estimate (62%). The CRS and LCA approaches, which utilized more than one diagnostic marker of pertussis, likely produced more accurate reference standards than culture alone. In general, the CRS approach is simple, with a well-defined disease status. LCA requires statistical modeling but incorporates more indicators of disease than CRS. When three or more indicators of pertussis are available, these approaches should be used in evaluations of pertussis diagnostic tests.

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How good are my data? Reference standards in superresolution microscopy

Molecular Biology of the Cell ◽

10.1091/mbc.e19-04-0189 ◽

2020 ◽

Vol 31 (19) ◽

pp. 2093-2096

Author(s):

Markus Mund ◽

Jonas Ries

Keyword(s):

Imaging Technique ◽

Reference Standards ◽

Reference Standard ◽

Yield Data ◽

Superresolution Microscopy ◽

Experimental Parameters ◽

Biological Discovery ◽

Microscopy Data ◽

Suitable Reference ◽

Over Time

Superresolution microscopy is becoming increasingly widespread in biological labs. While it holds enormous potential for biological discovery, it is a complex imaging technique that requires thorough optimization of various experimental parameters to yield data of the highest quality. Unfortunately, it remains challenging even for seasoned users to judge from the acquired images alone whether their superresolution microscopy pipeline is performing at its optimum, or if the image quality could be improved. Here, we describe how superresolution microscopists can objectively characterize their imaging pipeline using suitable reference standards, which are stereotypic so that the same structure can be imaged everywhere, every time, on every microscope. Quantitative analysis of reference standard images helps characterizing the performance of one’s own microscopes over time, allows objective benchmarking of newly developed microscopy and labeling techniques, and finally increases comparability of superresolution microscopy data between labs.

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Formative Evaluation of Ontology Learning Methods for Entity Discovery by Using Existing Ontologies as Reference Standards

Methods of Information in Medicine ◽

10.3414/me12-01-0029 ◽

2013 ◽

Vol 52 (04) ◽

pp. 308-316 ◽

Cited By ~ 4

Author(s):

K. J. Mitchell ◽

W. W. Chapman ◽

G. K. Savova ◽

N. Sioutos ◽

D. L. Rubin ◽

...

Keyword(s):

Formative Evaluation ◽

Performance Metrics ◽

Recognition System ◽

Reference Standards ◽

Entity Recognition ◽

Ontology Development ◽

Reference Standard ◽

Ontology Learning ◽

Step Method ◽

Optimum Parameters

SummaryObjective: Developing a two-step method for formative evaluation of statistical Ontology Learning (OL) algorithms that leverages existing biomedical ontologies as reference standards.Methods: In the first step optimum parameters are established. A ‘gap list’ of entities is generated by finding the set of entities present in a later version of the ontology that are not present in an earlier version of the ontology. A named entity recognition system is used to identify entities in a corpus of biomedical documents that are present in the ‘gap list’, generating a reference standard. The output of the algorithm (new entity candidates), produced by statistical methods, is subsequently compared against this reference standard. An OL method that performs perfectly will be able to learn all of the terms in this reference stand ard. Using evaluation metrics and precision-recall curves for different thresholds and parameters, we compute the optimum parameters for each method. In the second step, human judges with exper tise in ontology development evaluate each candidate suggested by the algorithm con figured with the optimum parameters previously established. These judgments are used to compute two performance metrics developed from our previous work: Entity Suggestion Rate (ESR) and Entity Acceptance Rate (EAR).Results: Using this method, we evaluated two statistical OL methods for OL in two medical domains. For the pathology domain, we obtained 49% ESR, 28% EAR with the Lin method and 52% ESR, 39% EAR with the Church method. For the radiology domain, we obtain 87% ESA, 9% EAR using Lin method and 96% ESR, 16% EAR using Church method.Conclusion: This method is sufficiently general and flexible enough to permit comparison of any OL method for a specific corpus and ontology of interest.

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