Reproducibility of African giant pouched rats detecting Mycobacterium tuberculosis.
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ABSTRACT: Background
African pouched rats sniffing sputum samples provided by local clinics have significantly increased tuberculosis case findings in Tanzania and Mozambique. The objective of this study was to determine the reproducibility of rat results.Methods
Over an 18-month period 11,869 samples were examined by the rats. Intra-rater reliability was assessed through Yule's Q. Inter-rater reliability was assessed with Krippendorff's alpha.Results
Intra-rater reliability was high, with a mean Yule's Q of 0.9. Inter-rater agreement was fair, with Krippendorf's alpha ranging from 0.15 to 0.45. Both Intra- and Inter-rater reliability was independent of the sex of the animals, but they were positively correlated with age. Both intra- and inter-rater agreement was lowest for samples designated as smear-negative by the clinics.Conclusion
Overall, the reproducibility of tuberculosis detection rat results was fair and diagnostic results were therefore independent of the rats used.
SUBMITTER: Ellis H
PROVIDER: S-EPMC5402322 | biostudies-literature | 2017 Apr
REPOSITORIES: biostudies-literature
Publications
Reproducibility of African giant pouched rats detecting Mycobacterium tuberculosis.
Ellis Haylee H Mulder Christiaan C Valverde Emilio E Poling Alan A Edwards Timothy T
BMC infectious diseases 20170424 1
<h4>Background</h4>African pouched rats sniffing sputum samples provided by local clinics have significantly increased tuberculosis case findings in Tanzania and Mozambique. The objective of this study was to determine the reproducibility of rat results.<h4>Methods</h4>Over an 18-month period 11,869 samples were examined by the rats. Intra-rater reliability was assessed through Yule's Q. Inter-rater reliability was assessed with Krippendorff's alpha.<h4>Results</h4>Intra-rater reliability was hi ...[more]
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