Comparative analysis of different diagnostic techniques for plasmodiasis

Abstract

The effectiveness in detecting malaria, of two immuno-chromatographic rapid diagnostic test (RDT) kits namely: .Global Devices One Step Rapid Test. and .SD-Bioline Malaria Pf/Pv. were evaluated by comparison with stained blood film microscopy. Blood samples of 202 patients with provisional diagnosis of malaria were tested in the laboratory for malaria parasites. The results of the stained film microscopy showed that 156 (77.2%) were positive, while the RDT kits . SD-Bioline and GlobalDevices showed positive results of 127 (62.9%) and 53(26.2%) respectively. The performance characteristics of the RDTkits, SD-Bioline and Global Devices, respectively were: sensitivity . 76.3% and 33.3%; specificity . 82.6 and 97.8%; test accuracy . 77.7% and 48.0%; positive predictive value . 93.7% and 98.1%; negative predictive value . 50.7% and 30.2%. Statistical tests of the effectiveness of the different techniques at p>0.05 and p>0.01 showed significant difference between the RDT kits andamong the three tests. Comparison of plasmodiasis infection rates between the sexes and among 4 age-groups: 0-11, 12-25, 26-49 and >50 showed no statistically significant difference at 5% and 1% alpha levels. The SD-Bioline Malaria Pf/Pv kit showed an appreciable effectiveness. It is therefore recommended for use in field screening, and in the absence of microscopist in the laboratory.