Commutability of a Whole-Blood External Quality Assessment Material for Point-of-Care C-Reactive Protein, Glucose, and Hemoglobin Testing.

BACKGROUND: The optimal situation in external quality assessment (EQA) is to use commutable materials. No previous study has examined the commutability of a whole-blood material for point-of-care (POC) testing. The aim of this study was to determine the commutability of the Norwegian Quality Improvement of Laboratory Examinations (Noklus) organization's "in-house" whole-blood EQA material for C-reactive protein (CRP), glucose, and hemoglobin for frequently used POC instruments in Norway and to determine the possibility of using a common target value for each analyte. METHODS: The study was performed according to the Clinical and Laboratory Standards Institute guidelines. The EQA material was pooled stabilized EDTA venous whole-blood containing different concentrations of the analytes. The EQA material and native routine patient samples were analyzed using 17 POC and 3 hospital instruments. The commutability was assessed using Deming regression analysis with 95% prediction intervals for each instrument comparison. RESULTS: The EQA material was commutable for all CRP and hemoglobin POC instruments, whereas for glucose the material was commutable for all POC instruments at the lowest concentration analyzed [126.0 mg/dL (7.0 mmol/L)] and for 3 POC instruments at all of the concentrations analyzed. CONCLUSIONS: Noklus EQA participants using CRP and hemoglobin POC instruments now receive results that are compared with a reference target value, whereas the results for participants using glucose POC instruments are still compared with method-specific target values. Systematic deviations from a reference target value for the commutable glucose POC instruments can be calculated, and this additional information can now be offered to these participants and to the manufacturers.

The microINR portable coagulometer: analytical quality and user-friendliness of a PT (INR) point-of-care instrument.

Regular measurement of prothrombin time as an international normalized ratio PT (INR) is mandatory for optimal and safe use of warfarin. Scandinavian evaluation of laboratory equipment for primary health care (SKUP) evaluated the microINR portable coagulometer (microINR®) (iLine Microsystems S.L., Spain) for measurement of PT (INR). Analytical quality and user-friendliness were evaluated under optimal conditions at an accredited hospital laboratory and at two primary health care centres (PHCCs). Patients were recruited at the outpatient clinic of the Laboratory of Medical Biochemistry, St Olav's University Hospital, Trondheim, Norway (n = 98) and from two PHCCs (n = 88). Venous blood samples were analyzed under optimal conditions on the STA-R®Evolution with STA-SPA + reagent (Stago, France) (Owren method), and the results were compared to capillary measurements on the microINR®. The imprecision of the microINR® was 6% (90% CI: 5.3-7.0%) and 6.3% (90% CI: 5.1-8.3) in the outpatient clinic and PHCC2, respectively for INR ≥2.5. The microINR® did not meet the SKUP quality requirement for imprecision ≤5.0%. For INR <2.5 at PHCC2 and at both levels in PHCC1, CV% was ≤5.0. The accuracy fulfilled the SKUP quality goal in both outpatient clinic and PHCCs. User-friendliness of the operation manual was rated as intermediate, defined by SKUP as neutral ratings assessed as neither good nor bad. Operation facilities was rated unsatisfactory, and time factors satisfactory. In conclusion, quality requirements for imprecision were not met. The SKUP criteria for accuracy was fulfilled both at the hospital and at the PHCCs. The user-friendliness was rated intermediate.

Effect of Participating in a Quality Improvement System over Time for Point-of-Care C-Reactive Protein, Glucose, and Hemoglobin Testing.

BACKGROUND: Users of point-of-care testing (POCT) in Norway participate in a quality improvement system that includes education and guidance in safe laboratory management along with participation in external quality assurance schemes (EQAS).The aim of this study was to identify the effect on the analytical performance of POCT C-reactive protein (CRP), glucose, and hemoglobin (Hb) with the use of a quality improvement system over time and to identify which factors are associated with good performance. METHODS: Participants' results from 19 EQAS for CRP, glucose, and Hb from 2006 to 2015 along with information on the instruments used and different practice characteristics were analyzed. Logistic regression analysis was used to evaluate the factors associated with good laboratory performance. An instrument evaluation and comparison for CRP determination was performed by using commutable EQA material. RESULTS: The mean number of participants in each EQAS was 2134, 2357, and 2271 for CRP, glucose, and Hb, respectively. The percentage of good participant performances increased gradually whereas that of poor performances decreased with participation in a quality improvement system over 9 years for all 3 analytes. Independent factors associated with good performance were type of instrument, the number of times performing EQA, performing internal QC weekly, performing 10 or more tests weekly, and having laboratory-qualified personnel perform the tests. Considering CRP instrument performance, Afinion and QuikRead exhibited the lowest systematic deviation. CONCLUSIONS: The analytical quality of CRP, glucose, and Hb testing is improved by systematic participation in a quality improvement system over time.

Point-of-care urine albumin in general practice offices: effect of participation in an external quality assurance scheme.

BACKGROUND: The Norwegian Quality Improvement of Primary Care Laboratories (Noklus) offers external quality assurance (EQA) schemes (EQASs) for urine albumin (UA) annually. This study analyzed the EQA results to determine how the analytical quality of UA analysis in general practice (GP) offices developed between 1998 (n=473) and 2012 (n=1160). METHODS: Two EQA urine samples were distributed yearly to the participants by mail. The participants measured the UA of each sample and returned the results together with information about their instrument, the profession and number of employees at the office, frequency of internal quality control (IQC), and number of analyses per month. In the feedback report, they received an assessment of their analytical performance. RESULTS: The number of years that the GP office had participated in Noklus was inversely related to the percentage of "poor" results for quantitative but not semiquantitative instruments. The analytical quality improved for participants using quantitative instruments who received an initial assessment of "poor" and who subsequently changed their instrument. Participants using reagents that had expired or were within 3 months of the expiration date performed worse than those using reagents that were expiring in more than 3 months. CONCLUSIONS: Continuous participation in the Noklus program improved the performance of quantitative UA analyses at GP offices. This is probably in part attributable to the complete Noklus quality system, whereby in addition to participating in EQAS, participants are visited by laboratory consultants who examine their procedures and provide practical advice and education regarding the use of different instruments.

Diagnosing microalbuminuria and consequences for the drug treatment of patients with type 2 diabetes: a European survey in primary care.

AIMS: To assess general practitioners (GPs) knowledge of guideline recommendations on diagnosing microalbuminuria (MA) and to evaluate how this diagnosis influences drug treatment of diabetes patients. METHODS: A postal case-history based questionnaire describing a male patient (previously not tested for MA) with type 2 diabetes who had several risk markers for cardiovascular disease. RESULTS: 2078GPs from nine European countries were included, with response rates varying from 7% to 43%. Almost all GPs recommended annual testing for MA. Forty-five to 77% (depending on country) of GPs required more than one positive test to diagnose MA. The absolute increase in the percentages of GPs who would supplement the patient's drug treatment if MA developed was: for anginotensin converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) 23-50% (depending on country), for statins 0-19%, for acetylsalicylic acid 2-13%, and for hypoglycemic agents (tablets and insulin) 0-33%. The proportion of GPs recommending all four possible treatment modalities was low. CONCLUSIONS: Guidelines for diagnosing MA were partly followed. ACEIs and ARBs were recommended when MA was present, but the recommended multifactorial treatment of cardiovascular risk markers was not implemented.

Postanalytical external quality assessment of urine albumin in primary health care: an international survey.

BACKGROUND: Microalbuminuria (MA) is recognized as an important risk factor for cardiovascular and renal complications in diabetes. We sought to evaluate how screening for MA is conducted and how urine albumin (UA) results are interpreted in primary care internationally. METHODS: General practitioners (GPs) received a case history-based questionnaire depicting a male type 2 diabetes patient in whom UA testing had not been performed. Questions were related to type of urine sample used for UA testing, need for a repeat test, whether UA testing was performed in the office laboratory, and what changes in UA results were considered clinically important [critical difference (CD)]. Participants received national benchmarking feedback reports. RESULTS: We included 2078 GPs from 9 European countries. Spot urine samples were used most commonly for first time office-based testing, whereas timed collections were used to a larger extent for hospital-based repeat tests. Repeat tests were requested by 45%-77% of GPs if the first test was positive. Four different measurement units were used by 70% of participants in estimating clinically important changes in albumin values. Stated CDs varied considerably among GPs, with similar variations in each country. A median CD of 33% was considered clinically important for both improvement and deterioration in MA, corresponding to an achievable analytical imprecision of 14%, when UA is reported as an albumin/creatinine ratio. CONCLUSIONS: Guidelines on diagnosing MA are followed only partially, and should be made more practicable, addressing issues such as type of samples, measurement units, and repeat tests.