Anne Kathryn Shephard

Assessment of the Nova StatSensor whole blood point-of-care creatinine analyzer for the measurement of kidney function in screening for chronic kidney disease

Abstract Background: Point-of-care testing for creatinine using a fingerprick sample and resultant estimated glomerular filtration rate has potential for screening for chronic kidney disease in community settings. This study assessed the applicability of the Nova StatSensor creatinine analyzer for this purpose. Methods: Fingerprick samples from 100 patients (63 renal, 37 healthy volunteers; range 46–962 μmol/L) were assayed using two StatSensor analyzers. Lithium heparin venous plasma samples collected simultaneously were assayed in duplicate using the isotope dilution mass spectrometry-aligned Roche Creatinine Plus enzymatic assay on a Hitachi Modular P unit. Method comparison statistics and the ability of the StatSensor to correctly categorise estimated glomerular filtration rate above or below 60 mL/min were calculated pre- and post-alignment with the laboratory method. Results: StatSensor 1 creatinine results (y) were much lower than the laboratory (y=0.75x+10.2, average bias –47.3, 95% limits of agreement –208 to +113 μmol/L). For estimated glomerular filtration rates above or below 60 mL/min, 100% and 87% of results respectively agreed with the laboratory estimated glomerular filtration rate (79% and 96% post-alignment). StatSensor 2 statistics were similar. The 95% limits of agreement between StatSensor creatinine results were –35 to +34 μmol/L. Conclusions: Isotope dilution mass spectrometry alignment of the StatSensor will identify most patients with estimated glomerular filtration rate <60 mL/min, but there will be many falsely low estimated glomerular filtration rate results that require laboratory validation. Creatinine results need improvement. Clin Chem Lab Med 2010;48:1113–9.

Design, implementation and results of the quality control program for the Australian government's point of care testing in general practice trial

Background From 2005 to 2007 the Australian Government funded a multicentre, clustered randomized controlled trial to determine the clinical effectiveness, cost-effectiveness, satisfaction and safety of point of care testing (PoCT) in general practice (GP). PoC tests measured (and devices used) in the trial were haemoglobin A1c and urine albumin:creatinine ratio (DCA 2000), lipids (Cholestech LDX) and international normalized ratio (CoaguChek S). Methods An internal quality control (QC) program was developed as part of a quality management framework for the trial. PoCT device operators were provided with a colour-coded QC Result Sheet and QC Action Sheet for on-site recording and interpreting of their results. Within-practice imprecision for QC testing was calculated and compared with the analytical goals for imprecision set prior to the trial. Results The average participation rate for QC testing was 91% or greater. Median within-practice imprecision met the analytical goals for all PoC tests, except for high-density lipoprotein-cholesterol (HDL-C) where observed performance was outside the minimum goal for one level and one lot number of QC. Most practices achieved the imprecision goals for all analytes, with the principal exception of HDL-C. Conclusions Results from QC testing indicate that PoCT in the GP trial met the analytical goals set for the trial, with the exception of HDL-C.

Results from 15 years of quality surveillance for a National Indigenous Point-of-Care Testing Program for diabetes

INTRODUCTION Diabetes is a major health problem for Australias Aboriginal and Torres Strait Islander peoples. Point-of-care testing for haemoglobin A1c (HbA1c) has been the cornerstone of a long-standing program (QAAMS) to manage glycaemic control in Indigenous people with diabetes and recently, to diagnose diabetes. METHODS The QAAMS quality management framework includes monthly testing of quality control (QC) and external quality assurance (EQA) samples. Key performance indicators of quality include imprecision (coefficient of variation [CV%]) and percentage acceptable results. This paper reports on the past 15years of quality testing in QAAMS and examines the performance of HbA1c POC testing at the 6.5% cut-off recommended for diagnosis. RESULTS The total number of HbA1c EQA results submitted from 2002 to 2016 was 29,093. The median imprecision for EQA testing by QAAMS device operators averaged 2.81% (SD 0.50; range 2.2 to 3.9%) from 2002 to 2016 and 2.44% (SD 0.22; range 2.2 to 2.9%) from 2009 to 2016. No significant difference was observed between the median imprecision achieved in QAAMS and by Australasian laboratories from 2002 to 2016 (p=0.05; two-tailed paired t-test) and from 2009 to 2016 (p=0.17; two-tailed paired t-test). For QC testing from 2009 to 2016, imprecision averaged 2.5% and 3.0% for the two levels of QC tested. Percentage acceptable results averaged 90% for QA testing from 2002 to 2016 and 96% for QC testing from 2009 to 2016. The DCA Vantage was able to measure a patient and an EQA sample with an HbA1c value close to 6.5% both accurately and precisely. CONCLUSION HbA1c POC testing in QAAMS has remained analytically sound, matched the quality achieved by Australasian laboratories and met profession-derived analytical goals for 15years.