Assessment of the inter-rater reliability of the microscopic diagnosis of malaria in three Health Centres of Kayonza District, Eastern Province, Rwanda

Abstract

Background: Globally, accurate diagnosis of malaria is essential for effective management of malaria and other frequently fatal non-malarial febrile illnesses that share the same signs and symptoms with malaria. Although malaria microscopic diagnosis using stained blood slides is considered to be a standard technique, it suffers subjectivity in its accuracy depending on the knowledge and skill of the technologist reading the slides. The purpose of this retrospective cross-sectional study done in 2013 was therefore to assess the reliability of microscopic diagnosis of malaria using stained blood slides by laboratory technologists in three Kayonza District health centres, Eastern Province, Rwanda.

Methods: Forty  archived stained blood slides of which 20 had been reported to be positive and 20 negative were selected from each of the three identified health centres by systematic sampling. Overall, 120 stained blood slides were collected and read by the Principal  Investigator, and the quality control was done by the National Reference Laboratory.

Results and conclusion The results of the diagnosis done by the health centre technologists and principal investigator agreed by 96.67% and was categorized as almost perfect according to the calculated Cohen’s kappa of 0.933, p<0.001. Still, more trainings are recommended for the technologists.

Key words: Microscopic Evaluation, Quality Control, Laboratory Technologist Malaria, Rwanda