加纳莱克马医院疟疾显微镜检查中的评分者间变异性

Inter-rater Variability in Malaria Microscopy at the LEKMA Hospital, Ghana.

作者信息

Bekoe Andrew Nii Adzei, Allotey Emmanuel Alote, Akorsu Elliot Elikplim, Abaka-Yawson Albert, Adusei Samuel, Kpene Godsway Edem, Kwadzokpui Precious Kwablah

机构信息

Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Health and Allied Sciences, Ho, Ghana.

Laboratory Department, Ledzokuku Krowor Municipal Assembly (LEKMA) Hospital, Accra, Ghana.

出版信息

J Parasitol Res. 2020 Dec 9;2020:8897337. doi: 10.1155/2020/8897337. eCollection 2020.

DOI:10.1155/2020/8897337

PMID:33489321

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7787828/

Abstract

BACKGROUND

Malaria remains a major cause of morbidity and mortality worldwide and particularly in sub-Saharan Africa where it is endemic. As such, it is important that a proper diagnosis is made before treatment is initiated. Malaria parasite count plays a key role in the diagnosis and management of malaria. Variations in ratings by laboratory personnel can impact negatively on the treatment regimen for malaria-infected patients. The study is thus aimed at evaluating and comparing the proficiency and parasitaemia counts by two different categories of laboratory staff at the LEKMA Hospital, Ghana.

MATERIALS AND METHODS

A total of 200 confirmed malaria-positive samples were used in the study. Six thick and thin films were prepared from each sample and uniquely labelled. Two of the six slides were given to two WHO-accredited malaria microscopists to examine and report their respective parasite count/l (parasite count/WBC × 8000). These were used as the reference for the two categories of laboratory staffs: rater A being diploma holders (Technical Officers referred to as untrained rater) and rater B being degree holders (Medical Laboratory Scientist referred to as trained rater) at the LEKMA Hospital.

RESULTS

In comparison to the expected outcome, the parasite count by the rater group A (190 (151-239)]) and the rater group B (177 (140-224)) demonstrated significant positive correlation ( = 0.995, < 0.0001 vs. = 0.995, < 0.0001, respectively) with the expected outcome in the cases of heavy parasitaemia. A statistically significant difference ( < 0.05) between counts by the different raters in low parasitemia was observed in this study. A persistent nosedive inter-rater agreement from = 0.82 to = 0.40 with increasing density cutoff was observed in this study.

CONCLUSION

The study observed that the degree of inter-rater agreement of parasite density count by various categories of laboratory personnel is almost perfect. However, the parasite count between raters varied significantly with very low levels of parasitemia but better correlated with heavy parasitemia.

摘要

背景

疟疾仍然是全球尤其是撒哈拉以南非洲地区发病和死亡的主要原因，该地区疟疾流行。因此，在开始治疗前进行正确诊断很重要。疟原虫计数在疟疾的诊断和管理中起着关键作用。实验室人员评级的差异可能会对疟疾感染患者的治疗方案产生负面影响。因此，本研究旨在评估和比较加纳莱克马医院两类不同实验室工作人员的熟练度和疟原虫血症计数。

材料与方法

本研究共使用了200份确诊的疟疾阳性样本。从每个样本中制备六张厚涂片和薄涂片，并进行唯一标记。将六张载玻片中的两张分别交给两名获得世界卫生组织认可的疟疾显微镜检查人员，让他们检查并报告各自的每升疟原虫计数（疟原虫计数/白细胞×8000）。这些用作两类实验室工作人员的参考：评级者A为文凭持有者（技术官员，称为未经培训的评级者），评级者B为学位持有者（医学检验科学家，称为经过培训的评级者），均来自莱克马医院。

结果

与预期结果相比，在高疟原虫血症病例中，评级者A组（190（151 - 239））和评级者B组（177（140 - 224））的疟原虫计数与预期结果显示出显著正相关（分别为r = 0.995，P < 0.0001和r = 0.995，P < 0.0001）。本研究观察到，在低疟原虫血症情况下，不同评级者的计数之间存在统计学显著差异（P < 0.05）。本研究还观察到，随着密度截断值的增加，评级者之间的一致性从κ = 0.82持续下降至κ = 0.40。