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Biomedical subjects

B E Copeland

Publications and source records attributed to B E Copeland.

At least 37 records · Page 2Linked to original sources
PubMed1976

Comparison of serum calcium measurements with respect to five models of atomic absorption spectrometers using NBS-AACC calcium reference method and isotope-dilution mass spectrometry as the definitive method.

Utilizing the recently described reference method for calcium (NBS-AACC) and the recently developed definitive (referee) NBS method for serum calcium measurement by isotopedilution mass spectrometry (IDMS), an evaluation of five recent-model atomic absorption spectrometers was carried out. Under optimal conditions of instrument operation using aqueous standards, significant differences were found during the comparative analyses of three lyophilized pool samples and one liquid serum pool sample. Use of the NBS-AACC serum calcium protocol did not guarantee analytic results within +/- 2% of the IDMS value. In four of eight comparisons, differences from IDMS greater than 2% were observed. Several variables were studied to account for these differences. It was shown that a serum matrix, when present in standards used to bracket the unknown sample, reduced differences between instruments in four of four instances and improved the accuracy of the results from a range of -1.1 to +3.5% to +0.1 to +1.0%. It is concluded that a serum sample with a verified IDMS calcium value is a valuable tool that establishes an accurate and stable reference point for serum calcium measurement. The use of transfer-of-NBS-technology multipliers is suggested. Regional quality control serum pools and clinical chemistry survey sample materials that have been analyzed for calcium concentration by the NBS-IDMS definitive method are examples of these multipliers.

Calcium↗
PubMed1975

An international laboratory survey.

Lyopholized and liquid aliquots of human serum and blood were distributed in 1973 and 1974 to 50 international medical laboratories that took part in a pilot study sponsored by the College of American Pathologists (CAP) and the Commission on World Standards of the World Association of Societies of Pathology (COWS/WASP). The results were compared with data derived from more than 4,000 United States laboratories that received the same samples. Sodium, potassium, urea nitrogen, glucose, hemoglobin and hematocrit assays show a strikingg similarity in mean values when the World group (COWS/WASP) is compared with participants in the United States. The results suggest that laboratory testing in the international group follows the pattern seen in the United States. The study measures differences and similarities and the collected data serve as a springboard for discussion on international standards of laboratory testing.

Africa↗
PubMed1968

Laboratory data.

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Blood Transfusion↗