UcliSens EasyQ 2.0 . Only one publication evaluated assays using HIV-2 AZ876 chemical information samples and the remainder used HIV-1 Group M, N, and O. There was no single standard reference test used as a comparator in all studies. Of the 37 included studies, 12 were published in 2009, with a minimum and maximum of 2000 and 2012 respectively. Study Selection The search was conducted in February 2010 and updated in April 2012 to include scientific research articles published in peerreviewed journals, in English, between January 1990 and the search date. Publications evaluating or comparing the performance of commercial assays for the quantification of HIV-1 or HIV-2 virus load in plasma were included in the search. There were no limitations on the method of nucleic acid extraction, amplification, or detection but the assays under investigation had to be commercially available at the time of the review. The study population was limited to adults but no restriction was placed on the geographical origin of the samples or the HIV subtype. 15481974 Publications using samples from standardized panels were also considered for inclusion providing they met the study criteria. No authors were contacted for further information and all data presented in this review were available in the included publications. Quantitative Data Synthesis: Accuracy of HIV VL Assays Analytical Sensitivity and Specificity of HIV VL Assays with Plasma. One study provided analytical sensitivity and Data collection processes Two independent reviewers extracted data on assay accuracy and reproducibility from publications meeting the inclusion criteria as defined in the protocol. Where there was any discrepancy, the reviewers met to discuss the difference and came to a consensus on inclusion or exclusion from the study. The quality of publications included in the HIV VL review was scored using adapted STARD guidelines. This included questions on the title and abstract; introduction; methods including participant/sample characteristics, test methods and statistical specificity data for ExaVir Load v3 compared to Amplicor Monitor v1.5 . Sensitivity of the ExaVir v3 was 96 100% at HIV VL concentrations above 2000 copies/mL, but decreases to 59% when VL concentration decreased to between 50400 copies/mL. The specificity of the ExaVir v3 was evaluated using HIV-1 negative samples and MedChemExpress Terlipressin reported as 100%. Five studies evaluated the specificity of the Amplicor v1.5, Abbott RealTime, bDNA 3.0, and ExaVir v3 assays using HIV-1 negative samples and reported as 100%. When tested with a panel containing four HIV-2, four HCV, and four polyomavirus BK plasma samples, the specificity of the kPCR was 92%. One study evaluated the specificity of the TaqMan v2.0 using HIV-1 negative samples containing potentially cross-reactive reactive viruses and found no false positive results or cross-reactivity. Clinically important differences in result. Seventeen studies evaluated the percentage of results differing by a clinically important value, defined as 0.5log10, between the index test and reference test. Data were available for Amplicor v1.5, TaqMan v2, Abbott RealTime, bDNA 3.0, kPCR, and ExaVir v3. Systematic Review of Viral Load Technologies Between 8.5% and 70.0% of results provided by the Abbott RealTime assay differed by greater than 0.5log10 compared to the Roche Monitor v1.5. The greatest differences in results occurred using the 1 mL Abbott RealTime sample input, where 70% of results differed by more than 0.5log10 compared.UcliSens EasyQ 2.0 . Only one publication evaluated assays using HIV-2 samples and the remainder used HIV-1 Group M, N, and O. There was no single standard reference test used as a comparator in all studies. Of the 37 included studies, 12 were published in 2009, with a minimum and maximum of 2000 and 2012 respectively. Study Selection The search was conducted in February 2010 and updated in April 2012 to include scientific research articles published in peerreviewed journals, in English, between January 1990 and the search date. Publications evaluating or comparing the performance of commercial assays for the quantification of HIV-1 or HIV-2 virus load in plasma were included in the search. There were no limitations on the method of nucleic acid extraction, amplification, or detection but the assays under investigation had to be commercially available at the time of the review. The study population was limited to adults but no restriction was placed on the geographical origin of the samples or the HIV subtype. 15481974 Publications using samples from standardized panels were also considered for inclusion providing they met the study criteria. No authors were contacted for further information and all data presented in this review were available in the included publications. Quantitative Data Synthesis: Accuracy of HIV VL Assays Analytical Sensitivity and Specificity of HIV VL Assays with Plasma. One study provided analytical sensitivity and Data collection processes Two independent reviewers extracted data on assay accuracy and reproducibility from publications meeting the inclusion criteria as defined in the protocol. Where there was any discrepancy, the reviewers met to discuss the difference and came to a consensus on inclusion or exclusion from the study. The quality of publications included in the HIV VL review was scored using adapted STARD guidelines. This included questions on the title and abstract; introduction; methods including participant/sample characteristics, test methods and statistical specificity data for ExaVir Load v3 compared to Amplicor Monitor v1.5 . Sensitivity of the ExaVir v3 was 96 100% at HIV VL concentrations above 2000 copies/mL, but decreases to 59% when VL concentration decreased to between 50400 copies/mL. The specificity of the ExaVir v3 was evaluated using HIV-1 negative samples and reported as 100%. Five studies evaluated the specificity of the Amplicor v1.5, Abbott RealTime, bDNA 3.0, and ExaVir v3 assays using HIV-1 negative samples and reported as 100%. When tested with a panel containing four HIV-2, four HCV, and four polyomavirus BK plasma samples, the specificity of the kPCR was 92%. One study evaluated the specificity of the TaqMan v2.0 using HIV-1 negative samples containing potentially cross-reactive reactive viruses and found no false positive results or cross-reactivity. Clinically important differences in result. Seventeen studies evaluated the percentage of results differing by a clinically important value, defined as 0.5log10, between the index test and reference test. Data were available for Amplicor v1.5, TaqMan v2, Abbott RealTime, bDNA 3.0, kPCR, and ExaVir v3. Systematic Review of Viral Load Technologies Between 8.5% and 70.0% of results provided by the Abbott RealTime assay differed by greater than 0.5log10 compared to the Roche Monitor v1.5. The greatest differences in results occurred using the 1 mL Abbott RealTime sample input, where 70% of results differed by more than 0.5log10 compared.
