Clinical features of the study participants.

Malaria rapid diagnostic test (mRDT) kit is one of the techniques for diagnosing malaria. Due to its inherent advantages over the microscopy technique, several brands of the kit have flooded malaria endemic countries, without prior in-country evaluation. Two of such mRDT kits are Oscar (India) and Standard Q (Korea Republic). In this study, the performance of Oscar and Standard Q mRDT kits were compared to First Response (India) and CareStart (USA) mRDTs, which have been evaluated and deployed for use approved by the Ministry of Health (MOH). In this comparative study, whole blood samples were collected from patients suspected of malaria. Plasmodium falciparum was detected in each sample using nested polymerase chain reaction (nPCR), microscopy and the four mRDTs. The sensitivities, specificities, accuracies, positive and negative predictive values and accuracies of the mRDTs were determined using nPCR as a reference technique. Kappa statistic was used to determine the level of agreement among the techniques. Two hundred (200) blood samples were analyzed in this study. The overall detection rates of P. falciparum by microscopy, First Response, CareStart, Oscar-PfHRP2, Standard Q mRDT kits and nPCR were 31.5%, 34.5%, 33.5%, 32%, 31% and 43% (x2 = 6.1, p = 0.046), respectively. The accuracies of CareStart and First Response were comparable (90.5% vs. 89.5%). Further, comparing their sensitivities, Oscar-PfHRP2 was 74.4% (95% confidence interval (CI): 63.9–83.2) while that of Standard Q was 72.1% (95% CI: 61.4–81.2), with comparable accuracies (Oscar-PfHRP2–89% and Standard Q -88%). Apart from First Response that was 98.3% specific, the others were 100% specific. Kappa test revealed perfect diagnostic agreement (κ = 0.90–0.98) among the four mRDTs. That notwithstanding, Oscar-PfHRP2 agreed better with CareStart (κ = 0.94) and First Response (κ = 0.92) compared to the agreement between Standard Q and, CareStart (κ = 0.92) and First Response (κ = 0.90). Taken together, the diagnostic performance of the four mRDT kits were statistically similar. That notwithstanding, new mRDT kits should be evaluated prior to deployment for use.疟疾快速诊断检测（mRDT）试剂盒是疟疾诊断的常用技术之一。相较于显微镜检测技术，该类试剂盒具有固有优势，目前已有多个品牌的mRDT试剂盒涌入疟疾流行国家，且未事先在当地开展评估。其中两款为印度产Oscar试剂盒与韩国产Standard Q mRDT试剂盒。本研究将Oscar及Standard Q mRDT试剂盒，与已通过卫生部门（Ministry of Health, MOH）批准评估并投入使用的First Response（印度产）及CareStart（美国产）mRDT试剂盒进行性能对比。在本对比研究中，研究人员从疑似疟疾患者体内采集全血样本。采用嵌套式聚合酶链式反应（nested polymerase chain reaction, nPCR）、显微镜检测及四款mRDT试剂盒，对每份样本中的恶性疟原虫（Plasmodium falciparum）进行检测。以nPCR作为参考方法，计算四款mRDT试剂盒的灵敏度、特异度、准确度、阳性预测值与阴性预测值。采用Kappa统计量评估各检测技术间的一致性水平。本研究共分析200份血液样本。显微镜检测、First Response、CareStart、Oscar-PfHRP2、Standard Q mRDT试剂盒及nPCR的恶性疟原虫总体检出率分别为31.5%、34.5%、33.5%、32%、31%及43%（χ²=6.1，P=0.046）。CareStart与First Response的准确度相当（90.5% vs. 89.5%）。进一步对比灵敏度可见，Oscar-PfHRP2的灵敏度为74.4%（95%置信区间（confidence interval, CI）：63.9–83.2），Standard Q的灵敏度为72.1%（95% CI：61.4–81.2），二者准确度相近（Oscar-PfHRP2为89%，Standard Q为88%）。除First Response的特异度为98.3%外，其余三款试剂盒的特异度均为100%。Kappa检验结果显示，四款mRDT试剂盒间均存在完美的诊断一致性（κ=0.90–0.98）。尽管如此，相较于Standard Q与CareStart（κ=0.92）及First Response（κ=0.90）之间的一致性，Oscar-PfHRP2与CareStart（κ=0.94）、First Response（κ=0.92）的一致性更佳。综合来看，四款mRDT试剂盒的诊断性能无统计学差异。但仍需注意，新型mRDT试剂盒在投入使用前应先开展评估工作。