Round 1 - Foundation for Innovative New Diagnostics

Figure 16 and 17 illustrates that high rates of detection of P. falciparum or of P. vivax were not associated with a significant
overall increase in false positive rates.
Figure 16: P. falciparum false positive rate 19 versus P. falciparum detection rate at low (200) parasite
density (parasites/μl)
50
False positive rate (%)
40
30
20
10
HRP2
pLDH
19
0
0 25 50 75 100
P. falciparum detection rate (%) at 200 parasites/µl
19 On the clean negative panel, only.
Figure 17: P. vivax false positive rate versus P. vivax detection rate at low (200) parasite density
(parasites/μl)
50
40
False positive rate (%)
30
20
10
pLDH
Aldolase
0
0 25 50 75 100
P. vivax detection rate (%) at 200 parasites/µl
10.3.7. Inter-reader variability
Each RDT result was read twice, the first, according to the
manufacturers minimum reading time and a second reading
was performed by a different technician within one hour.
The mean time between readings for each product can
be found in Tables A4.2, A4.3 (Annex 4). Figures 18 and
19 illustrate that for many products, the second reading
yielded more positive results. However, for two products
Reader 2 results returned fewer positive results secondary
to the fading of weak test band signals. In the case of 7
products 20 manufacturers specifically indicated that a
second reading should be performed if the initial results
were negative. Results are therefore reported on the basis
of the delayed reading in Tables 3a, 4a and in Annex 4
(Tables A4.1a, A4.4a-A4.12a)
20 Parascreen Rapid Test for Malaria (Pan/Pf) Device, Parabank Rapid Test
for Malaria Pan (Device), Malascan Rapid Test for Malaria Pf/Pan (Device),
ImmunoQuick Malaria + 4, Malaria Pf/vivax, Wondfo One Step Malaria Pf/
Pan Whole Blood Test, FirstSign – ParaView-2 (Pv + Pf) Card Test.
Malaria Rapid Diagnostic Test Performance – Results of WHO product testing of malaria RDTs: Round 1 (2008)
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