HIV抗体筛查实验的检测策略评价

目的以蛋白印迹试验（WB）结果为金标准,对实验室的HIV抗体筛查,包括酶联免疫吸附试验（ELISA）和免疫层析快诊实验的检测策略进行回顾性分析与评价。方法参照2004年《全国艾滋病检测技术规范》的要求,对2007-2011年之间HIV抗体初筛呈阳性反应的标本,采用WB进行确证。结果727例HIV抗体复查标本中,确证试验阳性为540例,占筛查阳性总数的74.28％;其中两种ELISA及免疫层析快诊都呈阳性反应的为558例,确诊540例,不确定’18例,与确证试验的阳性符合率为96.77％;其余的ELISA呈阳性反应结果加上快诊结果与WB的阳性符合率为0,其中不确定72例,阴性97例。ELISA结果的1≤S／Co〈3,与确证试验阳性符合率为0.85％;S／Co值在3～6之间,与确证试验阳性符合率为11.11％;S／Co〉6,与确证试验阳性符合率为94.51％。阳性与不确定’、阳性与阴性的S／Co、不确定。的各组之间差异均有统计学意义（P均=0.00）,不确定’与阴性之间差异有统计学意义（P=0.032）;而不确定。组之间差异均无统计学意义（均P〉0.05）。结论ELlSA检测试剂存在一定的假阳性,随着S／Co值的增高,与确证试验的阳性符合率也将升高,但是高S／Co值的样本并不代表感染HIV,HIV抗体阳性报告建议以确证试验结果为准;WB确证方法在不确定标本中存在一定的缺陷,快诊与ELISA的联合运用可以有效区分WB结果的感染一不确定与未感染一不确定,建议根据初筛结果,分类做好不确定人群的管理,尤其对两种ELISA及快诊均呈阳性反应的人群,应加大力度做好随访工作,确保无一例漏访。     

103例HIV检测第四代酶联免疫试验阳性而蛋白印迹试验阴性样本的分析

目的探讨蛋白印迹试验(WB)对第四代酶联免疫(ELISA)筛查试验艾滋病病毒(HIV)阳性样本确证检测的漏检问题及可能的解决办法。方法收集103例第四代ELISA筛查试验阳性、WB确证试验阴性的样本,进行HIV-1核酸套式聚合酶链反应(Nested-PCR)检测,并对HIV-1核酸阳性样本进行抗体追踪复检。结果 103例样本中,检出97例阴性,占94.17%;6例HIV-1阳性,占5.83%。97例阴性样本主要来源于没有或甚少高危行为的各类普通人群,且ELISA S/CO值多处于低值水平;6例阳性者均曾于近期有过相关接触史,其中ELISA S/CO值<6的2例,>6的4例,CD4+细胞数均低于正常值。结论实验室应采取措施对第四代ELISA阳性-WB阴性的艾滋病检测样本进行进一步诊断,以确定其真实的HIV-1感染状况,防止漏检。     

天津市HIV抗体检测中的替代策略研究

目的分析天津市2007-2009年人群HIV抗体检测数据,确定替代策略应用方案。方法对于接收的天津市艾滋病检测筛查实验室送检的1 636份样品,依据《全国艾滋病检测技术规范（2004年版）》规定的检测流程与方法进行HIV抗体确证。结果 2007-2009年共有1 039份样品经确证为HIV抗体阳性,进行艾滋病疫情报告例数为690例。ELISA S/CO≥6且快速检测阳性的1 028份样品,确证结果均为阳性。ELISA与快速检测结果不一致的124份样品,无确证结果为阳性者。结论在HIV低流行区将替代策略引入日常HIV抗体筛查检测,可以提高检测效率。通过身份信息核查,可以有效避免对继往感染者的重复确证。     

A simple and inexpensive particle agglutination test to distinguish recent from established HIV-1 infection.

OBJECTIVES: We sought to modify the Serodia HIV-1/HIV-2 particle agglutination assay (PA), a simple and cost-effective HIV assay that is used globally for the detection of HIV antibodies, as a sensitive/less sensitive test (S/LS) to identify recently infected individuals and to estimate HIV incidence. METHODS: The Serodia PA test was modified as an S/LS test (PA-LS) by using HIV antigen-coated gelatin particles at a dilution of 1:68 and a specific diluent, and calibrated using 37 HIV clade B seroconversion panels (309 samples) from Trinidad and from a commercial source that were tested at dilution intervals from 1:10 to 1:80,000. The greatest sensitivity for correctly classifying samples from recent and established infections was determined by receiver operator curve (ROC) analysis. RESULTS: At a 1:40,000 sample dilution and a days post-seroconversion cutoff of 190 days, the PA-LS test yielded a 97% sensitivity for classifying recent and established infection samples. Furthermore, at a 1:20,000 dilution, the positive predictive value for correctly identifying recently infected individuals was 99%. The PA-LS test offers a 30-44-fold cost saving over currently available S/LS tests. CONCLUSION: A modified, low cost and simple-to-perform PA test is appropriate for use in resource-limited countries, and has exhibited excellence in distinguishing recent from established HIV infection.     

Accuracy and Precision of a Point-of-Care HbA1c Test

Background:Point-of-care (POC) hemoglobin A1c (HbA1c) testing has advantages over laboratory testing, but some questions have remained regarding the accuracy and precision of these methods. The accuracy and the precision of the POC Afinion™ HbA1c Dx test were investigated.Methods:Samples spanning the assay range were collected from prospectively enrolled subjects at three clinical sites. The accuracy of the POC test using fingerstick and venous whole blood samples was estimated via correlation and bias with respect to values obtained by an NGSP secondary reference laboratory (SRL). The precision of the POC test using fingerstick samples was estimated from duplicate results by calculating the coefficient of variation (CV) and standard deviation (SD), and separated into its components using analysis of variance (ANOVA). The precision of the POC test using venous blood was evaluated from samples run in four replicates on each of three test cartridge lots, twice per day for 10 consecutive days. The SD and CV by study site and overall were calculated.Results:Across the assay range, POC test results from fingerstick and venous whole blood samples were highly correlated with results from the NGSP SRL (r = .99). The mean bias was −0.021% HbA1c (−0.346% relative) using fingerstick samples and −0.005% HbA1c (−0.093% relative) using venous samples. Imprecision ranged from 0.62% to 1.93% CV for fingerstick samples and 1.11% to 1.69% CV for venous samples.Conclusions:The results indicate that the POC test evaluated here is accurate and precise using both fingerstick and venous whole blood.     

Sensitivity and Specificity of Standard and Rapid HIV-Antibody Tests Evaluated by Seroconversion and Non-Seroconversion Low-Titre Panels

Background and objectives: The aim of this study is to compare the relative sensitivity and specificity of commercial HIV-antibody assays using seroconversion, non-seroconversion panels, and negative blood donor samples. Materials and methods: We evaluated the sensitivity of five standard ELISA HIV-antibody assays: Vironostika HIV Uni-Form II, Abbott recombinant HIV-1/HIV-2 third-generation EIA, Biotest Anti-HIV-1/-2 recombinant, Recombigen HIV-1/HIV-2 EIA and Wellcozyme HIV 1+2 (VK54/55), and three rapid screening tests, Capillus HIV-1/HIV-2, Abbott Test Pack HIV-1/HIV-2 third-generation EIA, and Sensy-Test HIV 1/2. All tests were assessed using four panels of plasma samples obtained from individuals who were seroconverting and a low-titre HIV-antibody panel of samples. Specificity of the standard screening tests was determined on 3,500 HIV-antibody-negative blood donor samples. Results: There was no statistically significant difference in sensitivity between the five standard ELISA tests. One of these tests was significantly less specific than the others. The standard ELISA tests detected all the low-titre HIV-antibody-positive samples. Two of the rapid screening tests were significantly less sensitive on the seroconversion panels and all three tests failed to detect at least one of the positive samples in the low-titre panel. Conclusions: The additional risk of using one or other of the standard ELISA tests under review of not detecting all HIV-positive units of blood is not statistically significant. Using some of the rapid screening tests will, however, add a significant additional risk. A rapid screening test should therefore be adopted only after careful consideration of the effect of a possible lack of sensitivity on the safety of the blood supply.     

Detection of HIV-1 RNA in Two Consecutive Blood Donations Screened Negative for HIV Antibodies

Background and Objectives: An unusual serological pattern of HIV-1 seroconversion in a blood donor is described. The seroconversion panel was used to investigate the sensitivity of existing screening assays. Materials and Methods: A volunteer blood donor who had given blood 79 times was diagnosed anti-HIV-1-antibody-positive. The heteroduplex mobility assay identified a subtype B HIV-1 strain. The frozen plasmas from the last four blood donations had been kept at ?30°C. They were thawed and aliquoted for subsequent testing. Results: The last two blood donations contained HIV-1 RNA, 2,800 copies/ml (October 26) and 170 copies/ml (November 23). Weak anti-p24 antibodies were detected by Western blot in the October 26 sample, and a clear p24 reactivity along with a faint gp 160 reactivity was oberved on November 23. HIV p24 antigen was undetectable in both samples. Out of 13 screening assays, only 6 gave positive results on the November sample and 7 negative results which were obtained by 1 competitive enzyme immunoassay (EIA) and 6 of the 9 sandwich EIAs. Conclusion: Most sandwich EIAs gave prolonged false-negative results in the present case. p24 antigen testing was negative and would not have reduced the risk of HIV transmission.     

Laboratory testing for infection with the human immunodeficiency virus: established and novel approaches

The enzyme-linked immunosorbent assay (ELISA) and the Western blot are the primary tests for the diagnosis and confirmation of human immunodeficiency virus (HIV) infection. The ELISA, an inexpensive screening test for antibodies to HIV-1, is both sensitive and specific. The HIV-1 Western blot is a reliable confirmatory test following a repeatedly reactive ELISA. False-positive HIV-1 results with this sequence of tests are extremely rare but can occur, and test results that are inconsistent with clinical or other laboratory information should be questioned, repeated, or supplemented. The US Food and Drug Administration has also approved rapid and more accessible testing methods. Oral mucosal transudate and urine testing are noninvasive testing methods; rapid and home sample collection kits offer easier access to testing.     

Rapid and specific diagnosis of HIV-1 and HIV-2 infections: an evaluation of testing strategies

To identify cost-effective testing strategies for HIV-1 and HIV-2 infections, we evaluated different combinations of tests on serum specimens from 1134 consecutive patients attending tuberculosis treatment centers in Abidjan, C?te d'lvoire. Virus-specific whole-virus enzyme-linked immunosorbent assay (WVE), Western blot (WB) and synthetic peptide enzyme-linked immunosorbent assay (SPE) were used in sequential fashion to determine the true prevalence of infection; 27% were reactive to HIV-1, 5% to HIV-2, and 10% to both viruses. Of 239 specimens positive on WB for both HIV-1 and HIV-2, SPE diagnosed 38% as HIV-1-reactive and 16% as HIV-2-reactive, while 46% remained reactive to both viruses. Using WVE or one of two rapid (5-10 min) mixed (HIV-1 and HIV-2) antigen tests (RMATs) as a screening test, followed by SPE as a supplemental test, gave results with sensitivity of 97.3-99.2%, specificity of 99.5-99.7%, and positive predictive value for diagnosing HIV infection of 99.4-99.6%, with important savings in time and reagent costs. SPE allows more specific distinction between HIV-1 and HIV-2 infections than WB, and could replace it as a supplemental test in many settings. WB may be required for specimens reactive on screening tests but negative on SPE, until sensitivity of the SPE is further evaluated. A mixed antigen screening test followed by SPE seems to be an efficient testing strategy for diagnosing HIV-1 and HIV-2 infections.     

Evaluation of a rapid test for the detection of antibodies to human immunodeficiency virus type 1 and 2 in the setting of multiple transmitted viral subtypes

Rapid HIV testing is an appealing strategy in the approach to HIV diagnosis in developing countries. Concern has been raised about the use of these tests in the setting of multiple transmitted HIV subtypes. We sought to compare the OraQuick(TM) HIV-1/2 Test, a qualitative immunochromatographic test for the detection of antibodies to HIV-1 and HIV-2 using stored sera, with a conventional enzyme immunoassay (EIA)/Western blot (WB) algorithm. The study design used was a blinded retrospective study. Samples were collected on patients attending sexually transmitted disease clinics and tuberculosis clinics in Kinshasa, the Democratic Republic of Congo and included 72 known HIV seropositive and 131 known HIV seronegative subjects. All 72 known HIV seropositive samples were positive by OraQuick and all 131 known HIV seronegative samples were negative by OraQuick resulting in 100% sensitivity and specificity. We conclude that the OraQuick rapid HIV-1/2 test performs well in the setting of diverse HIV viral subtypes.     

Evaluation of simple rapid HIV assays and development of national rapid HIV test algorithms in Dar es Salaam, Tanzania

Background  

Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA) or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from HIV-infected patients, pregnant women, voluntary counseling and testing attendees and blood donors, and to formulate an alternative confirmatory strategy based on rapid HIV testing algorithms suitable for use in Tanzania.     

Detection of early human T-cell lymphotropic virus type I antibody patterns during seroconversion among transfusion recipients

From a cohort of human T-cell lymphotropic virus type I (HTLV-I) exposed transfusion recipients (N = 71) enrolled in the Jamaican Transfusion Study, 11 were selected for detailed laboratory evaluation. All recipients were followed at monthly intervals for 6 months and then bimonthly up to 1 year for evidence of HTLV-I seroconversion. Without regard to results on screening assays, pretransfusion and posttransfusion samples were tested with two licensed HTLV-1 whole-virus screening enzyme immunoassays (EIAs), recombinant EIAs for antibody against tax (p40x) and p21e envelope, standard whole virus Western blot (WB), WB enhanced with recombinant p21e, and radioimmunoprecipitation assay (RIPA). In the early period posttransfusion, antibody to gag core protein was predominant with anti-p24 generally appearing before anti-p19. Recombinant anti-p21e envelope protein, in EIA and WB format, was frequently the earliest envelope reactivity detected, while anti-gp46 in WB and anti-gp61/68 in RIPA system appeared later. Anti-tax antibodies appeared later in the time course of seroconversion. The whole-virus EIAs were less sensitive than the confirmatory assays. The combination of WB and RIPA or WB enhanced with recombinant p21e appeared equally effective in confirming samples as positive by the Public Health Service two gene group confirmatory algorithm. However, specificity of this assay approach could not be addressed in this study.     

一例HIV抗体蛋白免疫印迹法检测条带不全病例的分析

目的通过对最近一例艾滋病病毒(HIV)抗体实验室检测"不确定"结果的分析讨论,尽可能减少实验室"不确定"结果的比例,提高实验室HIV确证实验的质量。方法该病例的血清标本采用两种酶联免疫吸附试验(ELISA)及两种快诊实验检测,又用蛋白免疫印迹法(WB)进行确证实验,并结合流行病学资料、核酸检测和基因测序结果,对该样本进行全面分析。结果 2012年11月至2013年3月期间,一例首次来自上海市肺科医院,两次随访均来自浦东新区自愿咨询检测门诊(VCT)的病例,ELISA和快诊检测为HIV抗体阳性,但WB确证结果首次为"不确定",第2、第3次随访结果也均为"不确定",后经核酸检测结果为阳性,基因测序结果为HIV-1型的CRF01_AE重组亚型,符合该病例的流行病学调查资料。结论对确证试验为"不确定"的病例,应综合初筛结果和实验室辅助检测手段及流行病学史,尽早明确个体HIV感染情况。     

Evaluation of an HIV screening assay kit for the combined detection of anti-HIV-1/2 antibodies and HIV p24 antigen]

We have evaluated a new HIV screening assay kit (Genscreen HIV Ag-Ab) for the HIV antigen-antibody combined test by comparing with two HIV antigen-antibody combined assay kits (VIDAS HIV DUO, Enzygnost HIV integral). Genscreen HIV Ag-Ab is a microwell plate enzyme immunoassay for the detection of HIV infection, based on the detection of anti-HIV-1/2 antibodies and HIV p24 antigen in human serum or plasma. In this study, 90 samples of HIV-1 antibody positive sera and 670 samples of HIV negative sera were examined. The sensitivity was 100% and the specificity was 99.7%. All of HIV-1 group M sera (subtypes A to G and B/D), HIV-1 group O sera and HIV-2 sera in worldwide HIV performance panel-302 were positive with Genscreen HIV Ag-Ab. Ten commercially available HIV-1 seroconversion panels were tested to evaluate sensitivity of three HIV antigen-antibody combined assay kits. Genscreen HIV Ag-Ab detected infection at the same bleeds as VIDAS HIV DUO in 8 of 10 seroconversion panels and 1 to 2 bleeds earlier than Enzygnost HIV integral in 5 of 10 seroconversion panels. However, VIDAS HIV DUO indicated false negative on 5th bleed in panel BB (PRA952). The result of the specimen was positive on 3rd bleed, equivocal on 4th bleed, negative on 5th bleed and again positive on 6th bleed. All of these specimens were positive by Genscreen HIV Ag-Ab. Therefore, Genscreen HIV Ag-Ab that shorten the window period is a useful and reliable for HIV screening test, especially in case of primary infection.     

Evaluation of a rapid test for the detection of antibodies to human immunodeficiency virus type 1 and 2.

Hema-Strip HIV-1/2 is a one-step rapid test for the detection of anti-HIV-1/2 antibodies in whole blood. The test requires no expensive equipment and the results are available within 10-15 min. Using 72 known HIV-1 positive samples and 780 high-risk prisoners, the sensitivity and specificity of Hema-Strip HIV-1/2 was found to be comparable to microparticle enzyme immunoassay (MEIA). The data also indicated that Hema-Strip HIV-1/2 is an effective alternate testing system to conventional ELISA where the use of ELISA is not suitable and the result of the HIV testing is needed urgently.     

Use of paper-absorbed fingerstick blood samples for studies of antibody to human immunodeficiency virus type 1 in intravenous drug users

The suitability of paper-absorbed (PA) fingerstick blood specimens for antibody testing of human immunodeficiency virus type 1 (HIV-1) was examined in two populations of intravenous drug users (IVDU): 393 persons from a drop-in counseling and testing clinic and 145 from a methadone treatment clinic. From the first group, the same 66 immunoblot-confirmed enzyme immunoassay (EIA)-positive specimens were identified in sera from venipuncture and parallel fingerstick PA specimens. The latter had slightly higher EIA mean background levels resulting in 10 immunoblot-negative EIA-positive samples versus 6 in the sera group. HIV-1 seroprevalence was 17% of 393 from the drop-in clinic. By category of IVDU, the rates were 34% and 14% for active and recovering IVDU, respectively (P less than .001), and 36% in black and Latino compared with 13% in white IVDU (P less than .002). Of the 145 participants in the methadone program, 39% had antibody to HIV-1: 49% for blacks and Latinos compared with 30% in whites (P less than .01). The data indicate that antibody testing for HIV-1 by PA is equivalent to the serum antibody assay of venipuncture specimens. The fingerstick method appears to have greater use for serosurveys and screening programs because of convenience, safety, and ease of storage, transport, and processing of samples.     

HIV and HTLV infections in 1305 transfusion-dependent thalassemics in Italy. The COOLEYCARE Cooperative Group.

OBJECTIVE: To evaluate the prevalence of antibodies to HIV-1/2 and HTLV-I/II in 1305 transfusion-dependent beta-thalassemics treated in 36 centres in Italy. DESIGN: Patient serum samples were collected during 1990 and tested in Milan. METHODS: Sera were screened using an enzyme-linked immunosorbent assay (ELISA) containing viral lysate antigens from HIV-1 and HIV-2, and a particle agglutination assay for the detection of antibodies to HTLV-I and HTLV-II. Repeatedly reactive samples were examined by Western blot (WB) assays containing recombinant and viral lysate antigens. Differential diagnosis was finally made by ELISA based on synthetic peptides. RESULTS: Samples from 36 of the 1305 patients (2.76%) contained anti-HIV-1 antibodies. In four patients seroconversion occurred after the implementation of anti-HIV-1 screening in blood donors in Italy (1985). Of the 36 HIV-1-antibody-positive samples, four were HIV-2 [corrected] WB indeterminate. These four samples were negative in assays based on specific synthetic peptides, suggesting cross-reactivity. Anti-HTLV-I antibodies were found in two patients from Sicily and one from Apulia, both southern Italian regions. Anti-HTLV-II antibodies were detected in another patient from Sicily. CONCLUSIONS: Antibodies to HIV-1, HIV-2, HTLV-I and HTLV-II were detected in 2.76, 0, 0.23 and 0.08% of patients, respectively. The residual risk of HIV-1 infection through blood transfusion after the implementation of anti-HIV-1 screening in blood donors in Italy was approximately 1:50,000 blood units; this is based on an approximate number of 200,000 blood units administered to our group of patients during 1986-1990 and the occurrence of four new anti-HIV-1 seroconversions. Seroconversions to HTLV-I/II suggest that these viruses are present in Italian blood donors.     

HIV抗体确证试验假阳性1例分析

目的通过对1例艾滋病病毒（HIV）抗体确证试验阳性者进行随访检测,探讨目前HIV抗体筛查和确证检测技术存在的问题。方法对受检对象进行HIV抗体筛查和确证试验,并于3、6个月和1年随访检测。结果首次筛查试验PA试剂为阴性,第3代梅里埃ELISA试剂为阳性,确证试验WB试剂检测带型gp120p24,判为HIV-1抗体阳性。比较试验第4代梅里埃ELISA试剂为阳性,金豪、吉比爱ELISA试剂为阴性,雅培硒标试剂为弱阳性。病毒载量检测结果为阴性。3次随访检测,筛查试验结果与首次检测基本一致,确证试验带型分别为gp120p24、p24和p24p55,1年后的病毒载量检测结果为阴性,受检对象随访后结果定为阴性。4次血样集中检测显示,筛查试剂批间无明显差异,但不同试剂间有差异;确证WB试剂不同批号间带型存在差异。结论目前应用的WB确证试剂存在一定的批间差异,对弱阳性带型或阳性带型不常见的样本,需更换试剂批号重复进行确证检测;确证试验结果处于临界阳性状态者需进行流行病学史调查;WB确证试验若同时出现1条env带和p24带判为HIV抗体不确定,并进行随访。     

Human immunodeficiency virus DNA amplification and serology in blood donors

The significance of indeterminate screening antibody test for human immunodeficiency virus (HIV) serology is still difficult to evaluate, especially in low-risk populations. One hundred twenty-seven blood donors with an initially reactive screening test for HIV antibodies were enrolled in this study. The sera of 95 of these blood donors were reactive on repetition of the test, and none had detectable circulating p24 antigen. Western blot (WB) analysis of the repeatedly reactive sera was as follows: 9 positive, 31 indeterminate, and 55 negative. One of the blood donors with indeterminate WB later presented a seroconversion. On subsequent control 3 to 12 months later, the sera from donors with indeterminate or negative WB did not present any parameters that may indicate a seroconversion. DNA was purified from citrated blood collected from the 127 blood donors at the time of the initial antibody screening. Five micrograms of each DNA sample corresponding to 7 x 10(5) nucleated white blood cells was amplified by polymerase chain reaction (PCR) in the presence of oligonucleotides (primers) corresponding to a highly conserved segment of the pol gene. The detection of amplified DNA was achieved by dot blot and Southern blot using appropriate 32P-labeled oligonucleotides. Ten DNA samples were positive, 9 corresponded to blood donors with a positive HIV serology, and 1 to the blood donor who later presented a seroconversion. These results confirm the sensitivity of the PCR for the diagnosis of HIV infection; they also suggest that repetition of the serology at 3- to 12-month intervals is a valuable procedure for the control of HIV infection status in blood donors.     

Fingerstick Precision and Total Error of a Point-of-Care HbA1c Test

Background:Point-of-care (POC) HbA1c tests hold the promise of reducing the rates of undiagnosed diabetes, provided they exhibit acceptable analytical performance. The precision and total error of the POC (Afinion™ HbA1c Dx) test were investigated using whole blood samples obtained by fingerstick and venipuncture.Methods:Fingerstick samples spanning the assay range were collected from 61 subjects at three representative POC sites. At each site, six fingerstick samples were obtained from each subject and tested on the POC test across two (Afinion AS100) instruments. Repeatability, between-operator, and between-instrument components of variance were calculated using analysis of variance (ANOVA). Four venous samples (low, threshold, medium, and high HbA1c) were measured in duplicate across three instruments using three reagent lots, twice per day over 20-days. Repeatability, between-run, between-day, between-lot, and between-instrument components of variance were calculated. These fingerstick and venous blood results, combined with estimates of imprecision and bias from a prior investigation, allowed for the calculation of the total coefficient of variation (CV) and total error of the POC test using fingerstick and venous whole blood samples.Results:The total imprecision ranged from 1.30% to 2.03% CV using fingerstick samples and from 1.31% to 1.64% CV using venous samples. The total error ranged from 2.87% to 4.75% using fingerstick samples and from 2.93% to 3.80% using venous samples.Conclusions:The POC test evaluated here is precise across its measuring range using both fingerstick and venous whole blood. The calculated total error of the test is well under the accepted quality requirement of ≤6%.