Foundation for Innovative New Diagnostics, 9 Chemin des Mines, 1202, Geneva, Switzerland.
Hospital for Tropical Diseases, Mortimer Market, London, WC1E 6JB, UK.
Malar J. 2018 Jan 15;17(1):29. doi: 10.1186/s12936-018-2173-0.
Malaria rapid diagnostic tests (RDTs) are becoming widely adopted for case management at community level. However, reports and anecdotal observations indicate that the blood transfer step poses a significant challenge to many users. This study sought to evaluate the inverted cup device in the hands of health workers in everyday clinical practice, in comparison with the plastic pipette, and to determine the volume accuracy of the device made of a lower-cost plastic.
The volume accuracy of inverted cup devices made of two plastics, PMMA and SBC, was compared by transferring blood 150 times onto filter paper and comparing the blood spot areas with those produced by 20 reference transfers with a calibrated micropipette. The ease of use, safety and acceptability of the inverted cup device and the pipette were evaluated by 50 health workers in Nigeria. Observations were recorded on pre-designed questionnaires, by the health workers themselves and by trained observers. Focus group discussions were also conducted.
The volume accuracy assessment showed that the device made from the low-cost material (SBC) delivered a more accurate volume (mean 5.4 μL, SD 0.48 μL, range 4.5-7.0 μL) than the PMMA device (mean 5.9 μL, SD 0.48 μL, range 4.9-7.2 μL). The observational evaluation demonstrated that the inverted cup device performed better than the pipette in all aspects, e.g. higher proportions of health workers achieved successful blood collection (96%, vs. 66%), transfer of the required blood volume (90%, vs. 58%), and blood deposit without any loss (95%, vs. 50%). Majority of health workers also considered it' very easy' to use (81%),'very appropriate' for everyday use (78%), and 50% of them reported that it was their preferred BTD.
The good volume accuracy and high acceptability of the inverted cup device shown in this study, along with observed ease of use and safety in hands of health workers, further strengthens prior findings which demonstrated its higher accuracy as compared with other BTDs in a laboratory setting. Altogether, these studies suggest that the inverted cup device should replace other types of devices for use in day-to-day malaria diagnosis with RDTs.
疟疾快速诊断检测（RDT）在社区层面上被广泛用于病例管理。然而，报告和轶事观察表明，血液转移步骤对许多使用者来说是一个重大挑战。本研究旨在评估在日常临床实践中卫生工作者使用倒置杯装置的情况，并与塑料移液管进行比较，同时确定由低成本塑料制成的装置的体积准确性。
通过将血液转移到滤纸上 150 次，并将血斑面积与经校准的微量移液管的 20 次参考转移进行比较，比较了两种塑料（PMMA 和 SBC）制成的倒置杯装置的体积准确性。50 名尼日利亚卫生工作者评估了倒置杯装置和移液管的易用性、安全性和可接受性。观察结果记录在预先设计的问卷上，由卫生工作者自己和经过培训的观察员记录。还进行了焦点小组讨论。
体积准确性评估表明，由低成本材料（SBC）制成的设备提供了更准确的体积（平均 5.4μL，SD 0.48μL，范围 4.5-7.0μL），优于 PMMA 设备（平均 5.9μL，SD 0.48μL，范围 4.9-7.2μL）。观察评估表明，在所有方面，倒置杯装置的性能均优于移液管，例如，更高比例的卫生工作者实现了成功的采血（96%，相比之下为 66%）、转移所需的血量（90%，相比之下为 58%），并且血液沉积无任何损失（95%，相比之下为 50%）。大多数卫生工作者还认为它“非常容易”使用（81%），“非常适合”日常使用（78%），并且 50%的人表示它是他们首选的 BTD。
本研究表明，倒置杯装置具有良好的体积准确性和高度的可接受性，再加上在卫生工作者手中观察到的易用性和安全性，进一步加强了之前的研究结果，即在实验室环境中，它比其他 BTD 具有更高的准确性。总之，这些研究表明，倒置杯装置应该替代其他类型的设备，用于日常疟疾诊断的 RDT。
