Volume 27, Number 3—March 2021
Systematic Review of Pooling Sputum as an Efficient Method for Xpert MTB/RIF Tuberculosis Testing during the COVID-19 Pandemic
|Study||Cartridge savings||Time savings, h (%)||Negative effects||Positive effects|
||Model of 1,000 patients with TB prevalence rate of 3% found 67.5% cartridge savings
||Lower sensitivity for smear-negative tuberculosis; requires laboratory infrastructure and training
||Processes higher volume of samples with fewer materials; time savings
|(12)||11% cartridge savings for hospital-based patients||377 (62%)||Steps involved heighten potential for errors||High-level agreement with individual Xpert results at reduced cost; substantial time savings to process hospital samples|
|41% cartridge savings for patients identified through active case finding
||Higher savings on cartridge cost and processing time for patients identified through active case finding
||Improved feasibility and cost-effectiveness of large-scale testing; reduced number of cartridges
||Increase in “error” results when using less buffer for pooling compared with standard buffer technique
||Reduced costs and number of cartridges
|(15)||27% (lower savings estimate using combination of approaches)||226/876 (26%) for all samples; 300/876 (30%) if hybrid approach used||NR||Method feasible; potential to reduce costs, increase throughput. Pooling can be used selectively if another screening test (e.g., radiograph) used for additional savings (hybrid approach)|
|34.5% (if used in patients with normal chest x-rays)
||Higher savings if only samples from patients without abnormal chest radiographs are included
||Method sensitive and cost-effective
|*NR, not reported.|
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