Can visual interpretation of NucliSens graphs reduce the need for repeat viral load testing? S1 Dataset
BACKGROUND: In Zimbabwe, viral load (VL) testing for people living with HIV on antiretroviral therapy is performed at the National Microbiology Reference Laboratory using a NucliSens machine. Anecdotal evidence has shown that invalid graphs for “Target Not Detectable (TND)” will upon repeat VL testing produce a valid result for virus not detected, therefore removing the need to repeat the test. This needs formal assessment.
OBJECTIVES: To determine i) intra- and inter-rater agreement of the visual interpretation of NucliSens graphs (Target Detectable [TD], TND and No Line [NL]) between two laboratory scientists and ii) sensitivity, specificity and predictive values of the NucliSens graphs compared with repeat VL results.
METHOD: Cross sectional study using secondary data. Two laboratory scientists independently rated graphs one week apart for intra-rater agreement and compared final ratings with each other for inter-rater agreement. Consensus interpretations of graphs were compared with repeat VL results. Kappa coefficients were used to obtain measures of agreement.
RESULTS: There were 562 patients with NucliSens graphs and repeat VL. Kappa scores were: 0.98 (Scientist A); 0.99 (Scientist B); 0.96 (Scientist A versus Scientist B); and 0.65 (NucliSens graphs versus VL). Sensitivity, specificity, positive predictive value and negative predictive value for graphs compared with VL were 71%, 92%, 79% and 89% respectively.
CONCLUSION: Intra-and inter-rater agreements were almost perfect. The negative predictive value translates to a false negative rate of 11%. If repeat VL testing is not done, the clinical consequences need to be balanced against cost savings and the risks outweigh the benefits.
Keywords
Antiretroviral therapy; HIV; Viral load; Zimbabwe; NucliSens graphsItem Type | Dataset |
---|---|
Resource Type |
Resource Type Resource Description Dataset Quantitative |
Capture method | Experiment |
Date | 20 November 2019 |
Language(s) of written materials | English |
Creator(s) |
Handireketi, N, Timire, C |
LSHTM Faculty/Department | Faculty of Infectious and Tropical Diseases > Dept of Clinical Research |
Participating Institutions | London School of Hygiene & Tropical Medicine, London, United Kingdom |
Date Deposited | 22 Nov 2019 12:51 |
Last Modified | 26 Jun 2025 08:59 |
Publisher | PLOS ONE |
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- Data record – Figshare (Data)
- S1 Data download - Figshare (Online Data Resource)
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- PLOS One (Paper)
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- Data record – Figshare (Data)
- S1 Data download - Figshare (Online Data Resource)
- S2 Data codebook - Figshare (Data)
- PLOS One (Paper)