An activity comparison of tritiated water was organized in 2013 between 3 laboratories: FTMC (Lithuania), LNE-LNHB (France) and VNIIM (Russia). The solution was prepared by LNHB and ampoules were sent to the others laboratories. This solution was standardized in terms of activity per unit mass by participant laboratories using the Triple to Double Coincidence Ratio (TDCR) method in liquid scintillation counting (LSC). The tritiated water solution is traceable to the solution prepared by LNHB for the CCRI(II)-K2.H-3 2009 (3)H international comparison.
To test whether academic centers (ACs) are more successful than nonacademic centers (NACs) in immunohistochemistry (IHC) external quality assessment challenges in the Canadian Immunohistochemistry Quality Control (CIQC) program.
Results of 9 CIQC challenges for breast cancer marker (BM) and various non-breast cancer marker (NBM) tests were examined. Success rates were compared between AC/NAC laboratories and those located in small or large cities. Performance was also correlated with annual IHC case volumes.
There was no statistically significant difference in performance in any of the comparisons. However, overall performance on BM was significantly better (P
We report the results of a province-wide quality control program in which five methicillin-resistant Staphylococcus aureus strains were circulated to all Ontario laboratories (hospital, private, and public health laboratories) on nine occasions between 1980 and 1989. The level of expression of methicillin resistance in each of the isolates was determined by performing viable colony counts on serial dilutions of methicillin in agar, and each isolate was assigned to an expression class according to previous published criteria (A. Tomasz, S. Nachman, and H. Leaf, Antimicrob. Agents Chemother. 35:124-129, 1991). Over this time there was an improvement in the performance of laboratories in the recognition of three strains that were relatively easy to detect (strains B, C, and E). These strains were of expression class II, and 98% of laboratories reported correct identifications in 1986. Performance in identifying two strains (strains A and D) of expression class I remained poor. Strain A was circulated in two surveys in 1987 and 1989, and laboratories were sent a questionnaire requesting details of the methods used in those two surveys. The methods used by the laboratories were classified into three categories: disk diffusion, single-plate screening by agar incorporation, and automated methods, which included premanufactured MIC panels. Between the 1987 and 1989 surveys, there was no change in the performance of the disk diffusion test (60% correct on both occasions), but there was improvement in the sensitivity of the agar incorporation test (36% correct in 1987 and 84% correct in 1989) and in automated methods (43% correct in 1987 and 79% correct in 1989). Over a decade, there was overall improvement in the performance of laboratories in detecting easy-to-detect strains, but there were difficulties in detecting organisms of low expression class, and an organism of very low expression class should be designated as a control organism for routine testing of methicillin-resistant s. aureus isolates.
Clinical guidelines are produced in order to achieve an acceptable standard of care, especially for patients with common diseases in primary care. The treatment of primary hypothyroidism serves as an example of the content of clinical guidelines and actual practice. The aim of this study was to compare the follow-up of primary hypothyroidism by thyroid function tests, serum TSH and serum-free T4, in older patients managed in primary care, with recommendations in treatment guidelines and textbooks.
Participation rate 82% (n=1260), mean age 74 years, (range 64-100 yrs). Patients with primary hypothyroidism were identified by means of cross-sectional survey (Lieto Study 1998-1999) and 4-year retrospective collection of laboratory database medical records (1994-1998), performed in autumn 2003.
In most stable (=treated for more than 14 months) thyroxine users, both serum TSH (mean 1.4 measurements/year) and serum-free T4 (mean 0.8 measurements/year) values were measured over the 4-year period of thyroxine treatment. 66.4% of serum TSH and 85.3% of serum-free T4 values were within normal range. 41.7% of serum-free T4 determinations had been performed without indication (=with TSH in normal range).
Compared with the recommended testing frequency given in various guidelines, a considerable number of extra measurements, especially serum-free T4, were performed. However, some key issues in the recommendations were difficult to interpret, and the age or other main characteristics of the patient were not taken into consideration adequately.
Autoantibody tests are often ordered inappropriately. We aimed to evaluate the ordering patterns of these tests in our local health region and to develop a laboratory algorithm aimed at reducing unnecessary tests. Laboratory data including the number and sequence of tests, ordering physician specialties and results for antinuclear (ANA), extractable nuclear antigen (ENA) and anti-double stranded DNA (anti-dsDNA) antibody tests from 2007 to 2009 were evaluated. Based on this information and a clinical consensus meeting, an algorithm was developed and applied retrospectively to 1 year of inpatient laboratory data to simulate potential cost savings. We identified a large volume of these autoantibody tests performed, equating to testing costs of $862,706.72, where less than 17 % of each were positive. Repeated ANA tests were mostly ordered after a previously negative result, and 1 % of patients with negative results changed to =1:160 on repeat testing. Close to half of all ENA and anti-dsDNA tests that were ordered were done so simultaneously with ANA, suggesting their use as screening tests. This was done more frequently in the inpatient setting. An algorithm was developed where ENA and anti-dsDNA tests would be cancelled if ANA was negative in the same sample. ANA repeated within 1 year would be cancelled and the prior result provided. Application of the algorithm retrospectively simulated a 30 % cost savings. Repeat testing and simultaneous ordering of multiple tests contributed to the excessive ordering of autoantibody tests in our health region. Our proposed algorithm would reduce testing costs and should be accompanied by appropriate educational information for physicians.
The Laboratory Proficiency Testing Program (LPTP) assesses the analytical performance of all licensed laboratories in Ontario. The LPTP Enzymes, Cardiac Markers, and Lipids Committee conducted a "Patterns of Practice" survey to assess the in-house quality control (QC) practices of laboratories in Ontario using cholesterol as the QC paradigm.
The survey was questionnaire-based seeking information on statistical calculations, software rules, review process and data retention, and so on. Copies of the in-house cholesterol QC graphs were requested. A total of 120 of 210 laboratories were randomly chosen to receive the questionnaires during 1995 and 1996; 115 laboratories responded, although some did not answer all questions.
The majority calculate means and standard deviations (SD) every month, using anywhere from 4 to >100 data points. 65% use a fixed mean and SD, while 17% use means calculated from the previous month. A few use a floating or cumulative mean. Some laboratories that do not use fixed means use a fixed SD. About 90% use some form of statistical quality control rules. The most common rules used to detect random error are 1(3s)/R4s while 2(2s)/4(1s)/10x are used for systematic errors. About 20% did not assay any QC at levels >5.5 mmol/L.
Quality control data are reviewed daily (technologists), weekly and monthly (supervisors/directors). Most laboratories retain their QC records for up to 3 years on paper and magnetic media. On some QC graphs the mean and SD, QC product lot number, or reference to action logs are not apparent. Quality control practices in Ontario are, therefore, disappointing. Improvement is required in the use of clinically appropriate concentrations of QC material and documentation on QC graphs.